as a machinist, seeing you use a boring bar as a fly cutter and just accepting the chatter gave me 13 types of cancer. This is why I watch this channel
All keeps did for me was given me post finasteride syndrome where I have partial eggplant dysfunction as far as getting to full muster and pretty consistent depression, takes years to shake, just warning Incase anyone clicks this and is considering finasteride
@unlisted9494 yikes man, sorry to hear that. I'm not intending to promote their product. I've never used it. Just thought the video would make a perfect ad for them.
@@8bithack Yep I was thinking the same thing. At least he should have fabricated a large disc with a lot of mass and attached a cutter to it instead of that chopstick of a boring bar
@@8bithack "It feels like he doesn't know what he's doing" I mean, most people in the auto industry that aren't running a machine shop don't actually know what they're doing when it comes to machining, and they have this equipment and the roughest knowledgeable about how to use it as a means to an end lol. Kinda like MIG/TIG welding in the knife making world, most of those dudes have absolutely NO idea how to use a welder, but they have one because they need to glue metal together during the knife making process and the weld quality just doesn't matter.
Thank you for being kind in the Chick-FilA drive thru! I hope you and your family are safe from the fires, I couldnt tell if you had to evacuate or not
Hell yeah! You made my night. It was a stressful day for Erica and the cats. She was parked in the parking lot waiting on me in her white hellcat. We were heading back home after the evac lifted
Rob can i stop by ? I'm an engineer and a machinist, i want to take a 3d scan of the 12 rotor and design and build a ITB setup for it just say Y or N in a reply and i will swing by with a laptop and a 3d scanner i might stop by with a few 3d prints for test fits before i handover all the cad files and i can do all the cam work with tool list so you can make the parts on the haas machine.
@Ownsterx I have been to the shop before lol. "Grove" lol, I don't want to say more than that I'm not in the mood for useless comments from people that don't understand anything. 🙃 I have worked with rob in the past he just doesn't know this is my youtube account. I'm a mechanical and electrical engineer and in the past did custom ecu systems for specialized applications in the military.
To figure out if there is a lack of flow or equal flow shouldn't you block off runners that will normally have the intake closed when the other is open? The air coming into the manifold will be at a constant velocity because there will always be lower pressure inside the manifold but each runner will have a pulsing airflow as the the rotor pulls in air and is then blocked. That brief period of time will change how much air is available to the other runners.
I think that would also not be a perfect representation because the cycles are so fast the air doesn't really have time to start and stop in each runner. That's why long runners can increase airflow at high RPM, the air just keeps moving in the runner and builds pressure (pulses) when the intake port is closed. What Rob is doing probably isn't perfect but probably close enough.
It won’t make enough difference to overcome just how bad the airflow is towards the front of the manifold. The pulses are just too short, especially with how fast rotaries run.
If the throttle blades move the velocity will change. If the RPM goes up or down the velocity will change. If boost is applied the velocity will change. Air will not change direction unless you make it change direction. The throttle bodies were too close to the front runners. Boost is a band aid for the issue since positive pressure can only be achieved once the manifold volume is exceeded. Given that the rotor is 1/3 the speed of the crankshaft it should be become obvious that 3 crankshaft revolutions are required to complete 1 full cycle of a rotor. Which yields a volume of approx 1.95 litres or 0.65 litres per rotor face. 12 rotors @ crankshaft revolution will result in 7.8 litres volume. So for 1 complete cycle 3 crankshaft are required, 10A, 12A, 13B, 20B, 26B or 12 rotor the crankshaft must complete 3 full revolutions to complete 1 rotor cycle. 23.4 litres by volume. They have some work to do.
Science teacher here, do the same test with a conical section for the meter instead of middle flow for my curiosity. Make the 3d printed flow adapter narrow at the exhaust end
Put the throttle on top in the middle of the intake lol! This shows what happends when boost is applied at wide open. With throttle blades at idle or low speed the front rotors would get most air more then likely.
1:15 Watching this made me have a seizure and when I came back my name was Watson, the year was 1880, and Sherlock was yelling at me "NO SHIT WATSON". Buy yourself some proper tools, a flycutter for one. I beg you Rob.
I’ve been checking multiple times over the past two weeks to make sure my notifications weren’t messed up. These videos are some of my favorite things to watch.
I’m dead when the music kicks back on and Rob gets into position for blowing his hair around lol. First time didn’t register, the 5th or 6th time I started to laugh.
11:30 Its so funny seeing him use the mass airflow sensor for each intake port like hes a doctor with a stethoscope checking you breathing and heart beats
Nobidy can convince me Rob didnt do the boring-fly-cutter-bar stunt on purpose to get engagement form machinists. He is too knowlegable at this point. And he is also diabolical like that 🤣
OMG! as a HVAC Commissioning Engineer using anemometers most days, and doing Test Adjust and Balance on ducted systems, I don't know what to make of this. One question - change in static pressure within the manifold under boost and with the pulses of each rotor? You have 'balanced' (kind of really proud of you for going down that rabbit hole BTW) in a fixed state, and not in the dynamic state in which it will operate ie: the rotors rotating, ignition pluses etc.
Not surprised the blowers have a calculated CFM lower than advertised, their own methodology to measure it when advertising is completely wrong, I believe ProjectFarmar and The Torque Test Channel did videos on blowers like these.
Rob had turned the power down because the test equipment couldn’t take full power and I don’t think the speed controls are that finely calibrated. I don’t doubt that there would have been less power if Rob could have checked that. The blowers are house hold tech and would lack efficiency, especially being used to blow through the header.
Don't forget the low-pressure areas that will pull air in. That cylinder that wasn't getting air in the sim would be in the real world. The engine creates a low pressure area on intake, forcing higher density air to fill the volume. Air is not pushed into the plenum on NA. It is pulled in by the engine creating low pressure areas. Flow rate would be measured by the air you can pull through each individual runner. Not pushed through from the throttle body side. Remember, engines are air pumps.
No, air is still getting pulled past those runners. Their testing is wrong. But your intuitive interpretation only works if you put a 500mm throttle body 50cm above the runners, with 10 cm between each. And that would run like a peice of shit. The other option is itb to atmosphere which works pretty good.
I agree that air pulled through a manifold might behave differently compared to air pushed through that same manifold. A second question that needs to be answered is how the sequence of the intake runners drawing air affects the other runners. Should they all draw from a single plenum, or should they resemble headers, and be paired according to firing order. Another topic: Should Rob just throw away the fancy electronic tools, and video his hair's reaction to each runner? Air speed could be estimated with the "hair movement" method, with the added benefit of being able to estimate turbulence by trying to run a comb through his hair after each runner test.
when i was watching all of the 12 rotor videos you made,the original owners video popped up on yt for me from 2016 or smth and was fun watching them start it up.
Rob, keep in mind that not all the inlet ports will be drawing in air simultaneously. Being a rotary, I'm way outside my wheelhouse but you'd be able to figure out how many ports will be drawing air at the same time. I'd avoid implementing any changes until this is taken into consideration and more testing is done. The test results would obviously be different.
A variable that needs to calculated in is the suctions on the intake cycle which should be identical on all ports. That in its self should even out the intake charge
To complicate things further, there's a pressure wave that travels back up the runners. When those pressure waves collide, it'll either make flow better or worse, and should be accounted for. I don't expect his team to have that expertise, but just pointing out how complicated intake design really is. Edit: I forgot this will be boosted, so it's a little less important
From the first time I saw that box/tube intake design, I knew it was not going to flow properly / equally to each rotor. Any successful hot rodder learned that in hot-rodding 101.
Can't wait to see this thing on the dyno, and then the process of installing it into the chosen vehicle. For sure going to be some more kinks along the way but the end product will be insane!
What if you build a lehmann intake for it? Seems like a great application for it. I think ideally you would use 3 plenums and 3 throttles, but that would be a pain. You could maybe do 1 large chamber or 2 smaller ones. With the single plenum you could have 3 equal slots feeding the banks. With 2 smaller ones you would have to carefully balance the area and have larger slots feeding the outside and a pair of smaller ones to the center bank. With the lehmann intake the area of the slot is usually about equal to the area of the tube feeding the manifold.
rob you need to calculate what ports overlap and then block all the others, then pressurize the manifold. the only issue with this method still is theres no vaccum drawn on the intake ports that are unblocked and the atmosphere would be pushing back against the leaf blowers.
im no manifold expert but im curious to hear from someone who does this stuff if this was actually helpful to the engine, wouldnt you want to simulate it in action since the manifold would be under pressure? and not all the ports will be open at the same time plus the pulse timing will affect the results
Agreed the flow of air will be dramatically changed in volume and pressure just by the ports being dead during compression and exhaust cycles. These readings are great to find the potential total flow of the intake but in a engine operation scenario the readings should also be taken port side like a vaccum instead of positive pressure from the throttle blade side. Though when the turbo is applied it will be a hybrid effect of some vaccum some forced induction.
Because the flow will change periodically there will be weird pressure waves in the intake. What is more worse, those waves will be different in every rpm scenario, with high and low pressure areas.
The thing is, the intake ports are essentially always open. because as soon as the end of the intake stroke of one of the rotor faces ends, the next rotor face is literally intaking air. every single time. Theres not really much of a wait at all.
hes not actually testing anything, the cfd and the leaf blower were all wrong. just disregard and read literature rather than watching a rich kid in a garage misleading the public
Another great video Rob always entertaining, I have owned an rx4 13b mild port and I know the importance of everything running in harmony or balance at the time the engine was using a twin point contact distributor, every month I had file down and adjust the gap or purchase a new set. The timing problem was fixed by upgrading to an electric distributor borrowed from the rx7 Rob, you seem to have most things covered Excellent ignition/timing Maybe too much fuel delivery What's letting you down is the air/fuel delivery but as you identified very uneven air pressure in the intake manifold. Possible short term solution add an individually adjustable flaps in the middle of the rams to equalise the air pressure. I'm sure your persistence will pay off all the very best.
Tell me how this guy is single-handedly going to eventually figure out how to build the most reliable and powerful engine at the same time with having probably very little degree in mechanical engineering this why we love you
You guys should look at the way the composite LS manifolds are made. They have those ripples in them that pull the air down into the intakes. need the volume but need to upset the air to capture it to move it down. No slip conditions to cause air to go where it needs. Just talking in text.
Individual intake plenums may actually help more then hurt. Running a turbo to each intake with individual throttle body's. And probably wouldn't look so off. And be able to simplify the intake air pressure
I’ve often wondered why intake manifolds frequently use a box like this to distribute air rather than a setup that mimics (in reverse) an x-into-one exhaust manifold. Equal length, I presume.
If you have to redesign, it might be worth it to build a way to get the turbos closer to the intake manifold. (Like make a cutout section) You might be able to build the intake and intercooler into one unit for when you will be compelled to put this in an FD. We are putting our faith in you Rotary Brother.
If he rebuilds it it might be worth going to completely separate 4 rotor intakes and exhausts. So it's like 3 separate engines hooked together. People assume engines geared together or combined in some way require perfect matching and tuning but they don't. Internal combustion engines are really, really forgiving about it when combined together. The stronger engine will just help spin the weaker engine faster. The weaker engine will just help slow down the stronger engine. It's shocking how different they can be and still work great because the engines do the job of self matching. There was a guy in California who put a motorcycle engine in the back of a Prius. Despite having the motorcycle engine in the back pushing it took no tuning of the Prius part to make it work. When he wants more speed he just turns on the motorcycle engine and it does it's thing in the back while the Prius does it's part in the front. That's an extreme of two totally different engines working together. Making each 4 rotor like it's own separate engine would simply things and help with packaging.
@ I am not convinced multiple Wankel rotaries would behave quite like that. Granted a 4 or 3 rotor have the best chance to, over for instance multiple sets of 2 rotors. I am willing to take your word for it though. I could easily see how a regular Ottocycle would behave like that though. Rotary Valves are actually really good compared to OHV. I dont know what that means for timing 3/6 sets of them that are apart. I think if they push/pulled each other it would create oscillations that would press on the side seals more. I am not sure it would help to multiplex them in the sense of saving space though. The injectors would be the difficult challenge of that idea or mainly the fuel rails. I think we need an iron with the turbo built into the center housing or a lovely tapestry of exhaust manifold with the hotside right in the manifold.
It doesn't matter after it's turbocharged....you created a massive pressure chamber....once at pressure each rotor will be drawing from the chamber....at 5psi none of that will matter anymore because there's high pressure zone seeking lows....flow becomes irrelevant as long as volume potentials are the same...
If that was true, we would not see a difference in using our turbo intakes with long runners vs. short runners. Just take a FAST LSX-R where you and change the runners. By changing them, you not only get the same difference you get N/A, what we also see, is that whether you run them N/A or forced induction, you still end up adjusting the same cylinders individually. Why? Because it acts the same and some ports are "favoured" no matter what. So, it does make sense to tune the manifold for best air distribution. Don't believe me? Ask the guys at Wilson, they do this all the time.
@AB-80X the only difference is reserve capacity of static charge pressure....capacity of stored high pressure air if there's 35 psi sitting at valve of cylinder 1 then there's 35 psi sitting at every other valve....variables being bigger chamber more turbo lag....
It's not a static environment. Air still has to flow from the throttle to the intake port, regardless of boost being present or not. The analogy of engines being air pumps still holds up regardless of whether the engine is boosted or not.
@TotoGeenen but it's going to be boosted.....the flow is gonna be pausing intermittently regardless due too only certain rotors drawing from the chamber anyways.....that chamber running is going to have the airflow of a pulse jet no matter how balanced flow at bench test gets
Great video. People make a lot of generalizations, ECU Capabilities are getting better and better and if all rotors were controlled individially you could compensate for any difference... but with such a simple test with varifyable difference before and after changes and to have the effects before and after coincide with the model its obviously effective. its a no brainer to do and probably something everyone should think about doing on modified engines. All the people that mention how it will be different in a running situation, who cares, any difference achieved at this point cant make it worse, only better!
I'm not sure if you'll see this or not but maybe there's an internal fin type thing you could add to the front of the intake on the inside to catch some of the air as it's passing by when there is no boost. Just a thought
I'm not sure you can judge anything by the freeflow CFM, and soon as there are rotors on the other side you'll get a lot of static pressure and the fuelmix will get pushed into the rotors.
I have made a intake-supercharger system, and thankfully did the air distribution design changes during the design phase, getting the maximum delta of 3%, and oh boy am i surprised by your airflow distribution results including the fact that you literally welded two sheet metal pieces at a almost random spot. Good stuff.
the intake is not a linear flowing device. Once the engine fires you will have laminar & non laminar flows, chaos, reversion, possible ram charge effects as the whole mix comes alive. Like they say "looked good on paper".....
You can increase the measurement range of your flow meter by allowing more air to get by the sensor in a controlled fashion. Instead of a straight port for the meter, expand it out like a trumpet, and measure farther away, where the air is expanding into the larger diameter. Also wouldn't hurt to put a couple layers of screening in the measuring tube before the meter, that way at least some of the port turbulence gets straightened out and evened out. With your current rig, you are only measuring speed at one specific spot in the airflow, and as your simulations show, the velocity can be very different just a few mm away. There is a reason most MAF sensors are behind a mesh of some sort, it's not to keep debris out, it's to help smooth the airflow as it passes. Most MAF screens are actually tiny tunnels, a mm or so long.
Blowing in the air should not be the same as the outlets demanding air. There is a pressure differential created at the intakes of the rotors. I may be wrong, but when you blow the air in, the density of the air will also be different. You should redo the simulation with the source at atmospheric pressure and the intakes at a lower pressure. You will see a change in CFD, and that is what you have to optimize.
You need to keep the anemometer in the same location for the 2 different output sizes. Even if the FT2 and CFM is the same, you’ll get different velocity readings by measuring in the center of 2 different shapes.
I think you have to calculate flow to the different ports based on when they open. All ports are not open at the same time. Also, the intake will be under boost and will flow based on the path of least resistance (open intake port), not in succession and not all at the same time. If you were doing a naturally aspirated intake, then the measurements you took would apply, but still only to the intake ports that were open simultaneously.
This test has little to do with reality. I designed the intake manifold. The main mistakes: 1.) The cylinders suck in the mixture 2.) They do it one by one 3.) The most important thing is that air has weight. The larger the turbine, the higher the pressure it pumps air with, the greater its weight. It is amazing to watch how the distribution of the gas flow changes when the turbine reaches the operating pressure. If at low loads, as a rule, the first cylinders receive more air if we are talking about an inline 6-cylinder engine, but at high loads, the last ones receive more air, due to the mass and energy of the gas. And if at low loads, due to the fact that the cylinders SUCK air, the disproportion is minimal, then at high gas consumption this can be 5-10-15%.
It's mainly a Marketing video from his sponsors. I've noticed people don't make videos anymore because it's fun but because they have to according to contracts.
if you use exhaust logic with the inake you cant use a boxy figgure start with a big tube like a collector and line that up in the front into 12 smaller tubes that way theres less turbulance and more directed airflow
Danke Ihnen Herr Dahm, gutes Video, mit deutlichster indirekter Fragestellung. Der Ansatz ist schon gut. Die in etwa Gleichflußfähigkeit des Luftverteilers ist eine gute Basis. Aber dies gilt nur an der Stelle wenn alle 12 Rotore an der Position Ladungswechsel stehen und die 12 Scheiben exakt Synchron laufen würden. Da bei dieser Maschine aber nur 4 Rotore gleichzeitig am Gleichflußpunkt stehen, ist es erforderlich den Test mit 8 geschloßenen Kanälen zu machen. Die 4 offenen dürfen dabei keine großen Unterschiede in der Durchflußmasse die Sekunde haben. Das gilt natürlich auch für die anderen beiden Gruppen die bei Weiterdrehen um 60° des Motors in diese Position des Ladungswechsel Gleichfluß kömmen. Der Abfluß könnte mit Pulsventielen versehen werden die das Laufen des Motors bis Nendrehzahl simulieren können. Dann währen auch die dynamischen Massestromumlenkungseffekte im Liefersystem in den Griff der Kompensation zu bekommen falls dies erforderlich sein würde. Q·E·D· Reiner Markenfreund von Michael Frithjof Müller.
This guy is making me look at rotary’s at 55, very cool and love learning. Is Mazda the only major manufacturer using rotary? My next vehicle I want to go 300 k with as least issues as possible.
measuring the resistance of the manifold you could do by measuring the consumed power of the two leaf blowers with and without the manifold connected and some changes to it
I'm reminded of the intake manifold of the BMW S62. That had a weird plenum thing full of intake runner pipes. That design of the box and pipe shape/design was to ensure proper flow to all cylinders.
Just a machinist’s opinion. For a motor that expensive, I would suggest sending things like the manifold out to get surface ground rather then flattening with a fly cutter. Get a much better surface finish quality, and more uniform finish.
I've researched decking heads a little and it seams like they like to fave the fly cut finish and I have not seen one pro using a surface grinder for a mirror finish.
G'Day Rob,,yes it make sence when you think about how the Blowers are shooting straight in for the front runners to run lean,,What you need to do is to make a restriction on all runners and allow the pressure to work on the flow,, so ifin you reduce the out let side of the manifold,(make the holes smaller),(just for testing) will make it more like the engine is running, giving you some back pressure in manifold,This will even out the different flows you are getting from each runner,,Pressure like water will always find the easist root to go,,with restrictions you will get better flow chararistics, Edit: Now all you have to diecide is how many rotor are on the same stroke at the same time,this will determine which rotor will get how much of the total mix going in, Even though you think you have to flow right,,some rotors may run lean depending on intake porting and where in the manifold it get the air from,
Seems like the leaf blower idea really worked well. Great idea! But, and I could be way off base here... I just keep thinking of the throttle bodies. The leaf blowers create a nice column of air and I'm sure they help to establish a nice baseline to measure from. I can't imagine the part throttle air will respond in a way that compliments all your hard work. 🤔 Anyway, just a thought I had. I know you guys will knock it out of the park in the end 👍
Should those turbos create a positive charge of air in the manifold which would solve your problem of low pressure in some runners and high in others? I could be wrong.
I did something vaguely similar with an evaporative ducted airconditioning system in my house. One duct was not getting much air. I mounted a vane internally to the dropper to deflect air to it, and suddenly it was getting the lion's share of the air. I had to reduce the vane size substantially to even it out.
Neat! Wouldn't you want high pressure air sitting as still as possible in the manifold, so it is available to go any direction (to the open port)? Could you make an upper plenum with larger openings for front ports that decrease in size for the rear ports?
I feel like your looking at airflow in the computer models. but if your intake manifold is under pressure like it should be once the turbos are running. I feel like once it’s under pressure because of back pressure. It will force the air into those first couple intakes that were not getting flow.
Being in the hvac industry specifically in the sheet metal fab and installation for over 45 years, and having to prove to young engineers what they draw on paper, and what according to theory works and doesn't work I'd say if you built z equally progressive set of curved blades into every intake opening then you should get equal flow if the air flows smoothly along your plenum. But this requires that you have true radius turns entering the plenum to eliminate the swirl that's causing the first few intake openings to be bypassed by your flow. But remember to step up each time you make a curved blade that has equal margine of straight flat at the beginning and ending of each louver to allow the air to enter smoothly, make it's way across the surface of the radius of the heel of the louver, and again slide across a short flat section as it enters the opening into head this will eliminate largest majority of the turbulence you will have had. I advise using smoke to verify your not introducing massive amounts of turbulence from your plenum into the head ports by using clear pipe attached to the plenum instead of the head itself to verify this and measure your air being pumped into your plenum, and measure the air flow entering each port to see how much static loss you have to allow you to make adjustments aa needed till true equal flow is reached and maximum flow is reached as well
The airflow needs to slow down as it enters the manifold. Push those throttle bodies away further and extend the manifold and or put a divider between the two sides. That should take care of most of your issues.
Rob, you should do some research on rally style dual plenum intake manifolds, they’re designed to promote even airflow even at high boost levels. Basically it’s just a tapered plenum connected to a log style manifold through a slot, kind of counter intuitive but it works better than ITBs on boosted applications.
You’re going to have to make it so the throttle bodies blades’ axis are 90 degrees of the new manifold directing blades, because the throttle body blades are kinda going to give the same effect already
Probably should get a machinist to do that for you. The ridges are from you not turning the x feed handle smoothly like a powerfeed would do. You also have your tool hanging out way to far which causes vibration and the bad finish you are getting. Push your tool back into the holder, speed up your spindle, slow down your cut feed rate and take shallower cuts.
The best power band is a wide one! No one is talking about the reflected intake pulses inside the manifold when the pressure isn't positive. The best way to test an intake manifold in on a running engine under all conditions. It's a game of compromises. Print the manifold. Test. Change. Compare. Repeat. Then make it durable (aluminum)!
You really should go do a machine shop course, you'd benefit alot because you know the things you want to be able to do and you pay attention enough to ask the right questions...
Hey Rob, I'm no rotary expert by any means but I am a retire mechanical and automotive engineer and I think you may be over looking something. Starting with the setup maybe it's the camera angle but at 7mins 45secs the blowers look level BUT the intake does not, the runners that are getting the most air look like they are in a different section of the air stream and the plenum design itself I think is also contributing to the problem because it slopes down towards the back which will increase the air speed to the back runners due to the venturi effect, maybe it's me but I think these things need to be looked into especially the plenum design, it need to have a more universal and volumetric shape and design. I hope you get what I mean mate, maybe I've got it all wrong. Seeya Rob............from Australia.
Rob you can take that boring bar and carefully bend it downwards in a vise just a hair and it will clear the bottom of your boring head.. I do that with the cheap bars the boring heads come with. Just make sure you bend it the right way lol
It could take years to work out all the air flow bugs !!! But what about a slight hour glass restriction in center ??? Rember Necola Testlas flow restrictor,filter ???
That manifold flange is pretty thin. High likelihood it warps again. Might be a good idea to go to a thicker flange and maybe even gusseting to give the whole assembly some more rigidity.
i would be concerned about the definite swirling that the airflow from the leaf blowers has impacting your results, i would re test with some form of 3d printed laminar flow filters, think like a tight honeycomb filled tube about 3 inches long
would the airflow to each cylinder change under boosted conditions? i feel like all the accumulated pressurized air in the manifold would just disperse evenly since the manifold is under pressure.
Not as odd as you think. I used to have a special boring head that was designed to face parts also, you held the 'adjuster' ring with an arm and it made the tool grow in diameter whilst cutting. It was probably so you can face a part like a cylinder barrel on a jig borer.
@@MrMaaaske95 It worked well enough for DIY in a hurry, but if you are paying a machinist and you see something like this don't go back. Not only is the surface finish terrible, it's bad for tooling longevity.
Yeah true. But I think the problem already starts with the fixture. I looks like the main flange is only supported by the intake runners which are in no way stiff enough to machine a truly flat surface
![Felix "Unfair" | [Stray Kids : SKZ-PLAYER]](http://i.ytimg.com/vi/Oswujxm2Ag0/mqdefault.jpg)
as a machinist, seeing you use a boring bar as a fly cutter and just accepting the chatter gave me 13 types of cancer. This is why I watch this channel
yea, that was rough.. He didnt understand why he had no clearance , or why there was chatter.
I now understand after watching it. I was legitimately going crazy hearing it.
That was crazy.. I'm surprised he didn't break the tool.
Rob “adderall” dahm at it again
@TeoGoYo bro has never once touched a lathe
The Keeps marketing people are foaming at the mouth over these shots of Rob's air blowing in the wind
All keeps did for me was given me post finasteride syndrome where I have partial eggplant dysfunction as far as getting to full muster and pretty consistent depression, takes years to shake, just warning Incase anyone clicks this and is considering finasteride
@unlisted9494 yikes man, sorry to hear that. I'm not intending to promote their product. I've never used it. Just thought the video would make a perfect ad for them.
@unlisted9494 yea that's a common side effect of finasteride. That's why minoxidil and liquid caffeine are the go-to's for regrowing hair
I literally lost all my hair on my head. The side effects where fucking terrible for me
11:30
13:22
1:36 Rob's machining is the epitome of ''If it looks stupid but works, it ain't stupid''.
That chatter is the sound of a terrible surface finish
No it can still be stupid you can gut your grass with scissors and it works but it’s stupid
It's definitely stupid... It feels like he doesn't know what he's doing. There's no reason to have that much of the tool sticking out.
@@8bithack Yep I was thinking the same thing. At least he should have fabricated a large disc with a lot of mass and attached a cutter to it instead of that chopstick of a boring bar
@@8bithack "It feels like he doesn't know what he's doing"
I mean, most people in the auto industry that aren't running a machine shop don't actually know what they're doing when it comes to machining, and they have this equipment and the roughest knowledgeable about how to use it as a means to an end lol. Kinda like MIG/TIG welding in the knife making world, most of those dudes have absolutely NO idea how to use a welder, but they have one because they need to glue metal together during the knife making process and the weld quality just doesn't matter.
Thank you for being kind in the Chick-FilA drive thru! I hope you and your family are safe from the fires, I couldnt tell if you had to evacuate or not
Hell yeah! You made my night. It was a stressful day for Erica and the cats. She was parked in the parking lot waiting on me in her white hellcat. We were heading back home after the evac lifted
Rob can i stop by ? I'm an engineer and a machinist, i want to take a 3d scan of the 12 rotor and design and build a ITB setup for it just say Y or N in a reply and i will swing by with a laptop and a 3d scanner i might stop by with a few 3d prints for test fits before i handover all the cad files and i can do all the cam work with tool list so you can make the parts on the haas machine.
No
Not happening lol
I'd love if he said yes. It would be so cool for you.
@Ownsterx I have been to the shop before lol.
"Grove"
lol, I don't want to say more than that I'm not in the mood for useless comments from people that don't understand anything.
🙃 I have worked with rob in the past he just doesn't know this is my youtube account. I'm a mechanical and electrical engineer and in the past did custom ecu systems for specialized applications in the military.
@@ZoeyR86 Hes named dropped mcfadden enough to figure out where he is
To figure out if there is a lack of flow or equal flow shouldn't you block off runners that will normally have the intake closed when the other is open? The air coming into the manifold will be at a constant velocity because there will always be lower pressure inside the manifold but each runner will have a pulsing airflow as the the rotor pulls in air and is then blocked. That brief period of time will change how much air is available to the other runners.
yea i kinda figured that wasnt quite right
I think that would also not be a perfect representation because the cycles are so fast the air doesn't really have time to start and stop in each runner. That's why long runners can increase airflow at high RPM, the air just keeps moving in the runner and builds pressure (pulses) when the intake port is closed. What Rob is doing probably isn't perfect but probably close enough.
It won’t make enough difference to overcome just how bad the airflow is towards the front of the manifold. The pulses are just too short, especially with how fast rotaries run.
If the throttle blades move the velocity will change. If the RPM goes up or down the velocity will change. If boost is applied the velocity will change.
Air will not change direction unless you make it change direction. The throttle bodies were too close to the front runners. Boost is a band aid for the issue since positive pressure can only be achieved once the manifold volume is exceeded.
Given that the rotor is 1/3 the speed of the crankshaft it should be become obvious that 3 crankshaft revolutions are required to complete 1 full cycle of a rotor. Which yields a volume of approx 1.95 litres or 0.65 litres per rotor face. 12 rotors @ crankshaft revolution will result in 7.8 litres volume.
So for 1 complete cycle 3 crankshaft are required, 10A, 12A, 13B, 20B, 26B or 12 rotor the crankshaft must complete 3 full revolutions to complete 1 rotor cycle. 23.4 litres by volume. They have some work to do.
@@tibo786 as they try measure the pressure drop the transient behavior is excluded. each channel on its own is the way to measure it correct.
Science teacher here, do the same test with a conical section for the meter instead of middle flow for my curiosity. Make the 3d printed flow adapter narrow at the exhaust end
separate intake manifold for each row. 3 throttle boddies!!! then u can optimize the runners for one then copy paste.
This is the right answer IMHO. It might need 3 MAF/MAP and a separate fuel table for each rail.
Put the throttle on top in the middle of the intake lol! This shows what happends when boost is applied at wide open. With throttle blades at idle or low speed the front rotors would get most air more then likely.
1:15 Watching this made me have a seizure and when I came back my name was Watson, the year was 1880, and Sherlock was yelling at me "NO SHIT WATSON". Buy yourself some proper tools, a flycutter for one. I beg you Rob.
I’ve been checking multiple times over the past two weeks to make sure my notifications weren’t messed up. These videos are some of my favorite things to watch.
As an avid fan of Alec Steele....
your machinist decisions are only answerable with a YES
It's a maybe, but it's also always yes.
I’m dead when the music kicks back on and Rob gets into position for blowing his hair around lol. First time didn’t register, the 5th or 6th time I started to laugh.
11:30 Its so funny seeing him use the mass airflow sensor for each intake port like hes a doctor with a stethoscope checking you breathing and heart beats
I can hear the communal groan from the machinist world. Jesus I could barely watch it happen.
Everybody starts somewhere
@@Waitin4_a_Mate gotta crawl before you can walk...and accept that you'll be handing your entire pocketbook over to the tooling companies.
Nobidy can convince me Rob didnt do the boring-fly-cutter-bar stunt on purpose to get engagement form machinists. He is too knowlegable at this point. And he is also diabolical like that 🤣
All I know is thatI don't know enough for this conversation. It is fun watching the video and going thru the comments and " Learning?" .
OMG! as a HVAC Commissioning Engineer using anemometers most days, and doing Test Adjust and Balance on ducted systems, I don't know what to make of this. One question - change in static pressure within the manifold under boost and with the pulses of each rotor? You have 'balanced' (kind of really proud of you for going down that rabbit hole BTW) in a fixed state, and not in the dynamic state in which it will operate ie: the rotors rotating, ignition pluses etc.
As an hvac tech i found it cool seeing rob unboxing a testo air flow / temp reader 😂
As a TAB guy, the only way to get a good reading on the runners is to traverse them haha
Not surprised the blowers have a calculated CFM lower than advertised, their own methodology to measure it when advertising is completely wrong, I believe ProjectFarmar and The Torque Test Channel did videos on blowers like these.
Rob had turned the power down because the test equipment couldn’t take full power and I don’t think the speed controls are that finely calibrated. I don’t doubt that there would have been less power if Rob could have checked that. The blowers are house hold tech and would lack efficiency, especially being used to blow through the header.
15 min of watching Rob’s hair get blown back like he’s in a photoshoot lol
Rob = Fabio electric boogaloo
Best keeps ad
He likes it too, secretly of course
@@jmazoso Robio, you mean 🤣
@@squidikka done deal!!!
Don't forget the low-pressure areas that will pull air in. That cylinder that wasn't getting air in the sim would be in the real world. The engine creates a low pressure area on intake, forcing higher density air to fill the volume.
Air is not pushed into the plenum on NA. It is pulled in by the engine creating low pressure areas. Flow rate would be measured by the air you can pull through each individual runner. Not pushed through from the throttle body side.
Remember, engines are air pumps.
This
No, air is still getting pulled past those runners. Their testing is wrong. But your intuitive interpretation only works if you put a 500mm throttle body 50cm above the runners, with 10 cm between each. And that would run like a peice of shit. The other option is itb to atmosphere which works pretty good.
What cylinder?
I agree that air pulled through a manifold might behave differently compared to air pushed through that same manifold. A second question that needs to be answered is how the sequence of the intake runners drawing air affects the other runners. Should they all draw from a single plenum, or should they resemble headers, and be paired according to firing order.
Another topic:
Should Rob just throw away the fancy electronic tools, and video his hair's reaction to each runner? Air speed could be estimated with the "hair movement" method, with the added benefit of being able to estimate turbulence by trying to run a comb through his hair after each runner test.
Just a tip, You could use a fly cutter instead of a boring head. lol
Crazy to see Rob using HVAC tools I use on the job but repurposing them for the 12 rotor.
What was the air temperature tool called?
when i was watching all of the 12 rotor videos you made,the original owners video popped up on yt for me from 2016 or smth and was fun watching them start it up.
Rob, keep in mind that not all the inlet ports will be drawing in air simultaneously.
Being a rotary, I'm way outside my wheelhouse but you'd be able to figure out how many ports will be drawing air at the same time. I'd avoid implementing any changes until this is taken into consideration and more testing is done. The test results would obviously be different.
A variable that needs to calculated in is the suctions on the intake cycle which should be identical on all ports. That in its self should even out the intake charge
Was just going to type this!
To complicate things further, there's a pressure wave that travels back up the runners. When those pressure waves collide, it'll either make flow better or worse, and should be accounted for. I don't expect his team to have that expertise, but just pointing out how complicated intake design really is.
Edit: I forgot this will be boosted, so it's a little less important
Boosted
Can you explain further?
@sethwalraven7786 3 massive turbochargers will force compressed air into the intake making the vacuum of the motor less relevant.
From the first time I saw that box/tube intake design, I knew it was not going to flow properly / equally to each rotor.
Any successful hot rodder learned that in hot-rodding 101.
Can't wait to see this thing on the dyno, and then the process of installing it into the chosen vehicle. For sure going to be some more kinks along the way but the end product will be insane!
I'm pretty sure this is going on a boat... I get that information from one of the first 12 Rotor videos if not the first.
@@KSwapTheWorld69this 12 rotor came from someone who had it in a boat but was naturally aspirated
@joeykeegan6909 oh wait this is his now? Or I'm sorry I don't really know...😅
@@KSwapTheWorld69 This is the same 12 rotor that there were videos of many many years ago.
It was meant for a boat but Rob is doing something else.
@NorwayVFX ahhh
What if you build a lehmann intake for it? Seems like a great application for it. I think ideally you would use 3 plenums and 3 throttles, but that would be a pain. You could maybe do 1 large chamber or 2 smaller ones. With the single plenum you could have 3 equal slots feeding the banks. With 2 smaller ones you would have to carefully balance the area and have larger slots feeding the outside and a pair of smaller ones to the center bank.
With the lehmann intake the area of the slot is usually about equal to the area of the tube feeding the manifold.
rob you need to calculate what ports overlap and then block all the others, then pressurize the manifold. the only issue with this method still is theres no vaccum drawn on the intake ports that are unblocked and the atmosphere would be pushing back against the leaf blowers.
I wish I was real life friends with Rob. He really is a cool guy.
Not an indicator in sight, it’s flat based on vibes 😂😂
Spiritually flat 😂😂
@@RobDahmlove it bro, go blue!
im no manifold expert but im curious to hear from someone who does this stuff if this was actually helpful to the engine, wouldnt you want to simulate it in action since the manifold would be under pressure? and not all the ports will be open at the same time plus the pulse timing will affect the results
Pulse timing isn't much for rotory
This only works on rotory since it's one stroke
For 2 n 4 yeah ur more right depending on engine and charge
Since 3/4 of the rotors aren’t open at a time, doesn’t it need to be tested with only the ones that are open in the firing order?
Agreed the flow of air will be dramatically changed in volume and pressure just by the ports being dead during compression and exhaust cycles. These readings are great to find the potential total flow of the intake but in a engine operation scenario the readings should also be taken port side like a vaccum instead of positive pressure from the throttle blade side. Though when the turbo is applied it will be a hybrid effect of some vaccum some forced induction.
Because the flow will change periodically there will be weird pressure waves in the intake. What is more worse, those waves will be different in every rpm scenario, with high and low pressure areas.
The thing is, the intake ports are essentially always open. because as soon as the end of the intake stroke of one of the rotor faces ends, the next rotor face is literally intaking air. every single time. Theres not really much of a wait at all.
hes not actually testing anything, the cfd and the leaf blower were all wrong. just disregard and read literature rather than watching a rich kid in a garage misleading the public
literally nobody made you watch his video. Move along.
Another great video Rob always entertaining, I have owned an rx4 13b mild port and I know the importance of everything running in harmony or balance at the time the engine was using a twin point contact distributor, every month I had file down and adjust the gap or purchase a new set. The timing problem was fixed by upgrading to an electric distributor borrowed from the rx7
Rob, you seem to have most things covered
Excellent ignition/timing
Maybe too much fuel delivery
What's letting you down is the air/fuel delivery but as you identified very uneven air pressure in the intake manifold.
Possible short term solution add an individually adjustable flaps in the middle of the rams to equalise the air pressure.
I'm sure your persistence will pay off all the very best.
Tell me how this guy is single-handedly going to eventually figure out how to build the most reliable and powerful engine at the same time with having probably very little degree in mechanical engineering this why we love you
You guys should look at the way the composite LS manifolds are made. They have those ripples in them that pull the air down into the intakes. need the volume but need to upset the air to capture it to move it down. No slip conditions to cause air to go where it needs. Just talking in text.
Individual intake plenums may actually help more then hurt. Running a turbo to each intake with individual throttle body's. And probably wouldn't look so off. And be able to simplify the intake air pressure
I’ve often wondered why intake manifolds frequently use a box like this to distribute air rather than a setup that mimics (in reverse) an x-into-one exhaust manifold. Equal length, I presume.
What an awesome project you Guys. Thank you for bringing us along.
If you have to redesign, it might be worth it to build a way to get the turbos closer to the intake manifold. (Like make a cutout section)
You might be able to build the intake and intercooler into one unit for when you will be compelled to put this in an FD.
We are putting our faith in you Rotary Brother.
If he rebuilds it it might be worth going to completely separate 4 rotor intakes and exhausts. So it's like 3 separate engines hooked together.
People assume engines geared together or combined in some way require perfect matching and tuning but they don't.
Internal combustion engines are really, really forgiving about it when combined together. The stronger engine will just help spin the weaker engine faster. The weaker engine will just help slow down the stronger engine.
It's shocking how different they can be and still work great because the engines do the job of self matching.
There was a guy in California who put a motorcycle engine in the back of a Prius. Despite having the motorcycle engine in the back pushing it took no tuning of the Prius part to make it work. When he wants more speed he just turns on the motorcycle engine and it does it's thing in the back while the Prius does it's part in the front. That's an extreme of two totally different engines working together.
Making each 4 rotor like it's own separate engine would simply things and help with packaging.
@ I am not convinced multiple Wankel rotaries would behave quite like that. Granted a 4 or 3 rotor have the best chance to, over for instance multiple sets of 2 rotors. I am willing to take your word for it though. I could easily see how a regular Ottocycle would behave like that though.
Rotary Valves are actually really good compared to OHV. I dont know what that means for timing 3/6 sets of them that are apart. I think if they push/pulled each other it would create oscillations that would press on the side seals more.
I am not sure it would help to multiplex them in the sense of saving space though. The injectors would be the difficult challenge of that idea or mainly the fuel rails.
I think we need an iron with the turbo built into the center housing or a lovely tapestry of exhaust manifold with the hotside right in the manifold.
The throttle bodies are also going to change the direction of flow
It doesn't matter after it's turbocharged....you created a massive pressure chamber....once at pressure each rotor will be drawing from the chamber....at 5psi none of that will matter anymore because there's high pressure zone seeking lows....flow becomes irrelevant as long as volume potentials are the same...
If that was true, we would not see a difference in using our turbo intakes with long runners vs. short runners. Just take a FAST LSX-R where you and change the runners. By changing them, you not only get the same difference you get N/A, what we also see, is that whether you run them N/A or forced induction, you still end up adjusting the same cylinders individually. Why? Because it acts the same and some ports are "favoured" no matter what. So, it does make sense to tune the manifold for best air distribution. Don't believe me? Ask the guys at Wilson, they do this all the time.
@AB-80X the only difference is reserve capacity of static charge pressure....capacity of stored high pressure air if there's 35 psi sitting at valve of cylinder 1 then there's 35 psi sitting at every other valve....variables being bigger chamber more turbo lag....
It's not a static environment. Air still has to flow from the throttle to the intake port, regardless of boost being present or not. The analogy of engines being air pumps still holds up regardless of whether the engine is boosted or not.
@TotoGeenen but it's going to be boosted.....the flow is gonna be pausing intermittently regardless due too only certain rotors drawing from the chamber anyways.....that chamber running is going to have the airflow of a pulse jet no matter how balanced flow at bench test gets
Great video. People make a lot of generalizations, ECU Capabilities are getting better and better and if all rotors were controlled individially you could compensate for any difference... but with such a simple test with varifyable difference before and after changes and to have the effects before and after coincide with the model its obviously effective. its a no brainer to do and probably something everyone should think about doing on modified engines. All the people that mention how it will be different in a running situation, who cares, any difference achieved at this point cant make it worse, only better!
As Arte Johnson used to say on Laugh-In, "Veeeery Interesting" Good practical adaptation of leaf blowers and an airflow sensor.
I started following you when you started the 4 rotor rx7 project and man what a build
I'm not sure if you'll see this or not but maybe there's an internal fin type thing you could add to the front of the intake on the inside to catch some of the air as it's passing by when there is no boost. Just a thought
I'm really liking your approach to finding flow differences.
I wonder if putting the throttle bodies on the top middle would solve the inconsistency. More like a 350 chevy type shape.
I'm not sure you can judge anything by the freeflow CFM, and soon as there are rotors on the other side you'll get a lot of static pressure and the fuelmix will get pushed into the rotors.
I have made a intake-supercharger system, and thankfully did the air distribution design changes during the design phase, getting the maximum delta of 3%, and oh boy am i surprised by your airflow distribution results including the fact that you literally welded two sheet metal pieces at a almost random spot. Good stuff.
the intake is not a linear flowing device. Once the engine fires you will have laminar & non laminar flows, chaos, reversion, possible ram charge effects as the whole mix comes alive. Like they say "looked good on paper".....
You can increase the measurement range of your flow meter by allowing more air to get by the sensor in a controlled fashion. Instead of a straight port for the meter, expand it out like a trumpet, and measure farther away, where the air is expanding into the larger diameter. Also wouldn't hurt to put a couple layers of screening in the measuring tube before the meter, that way at least some of the port turbulence gets straightened out and evened out. With your current rig, you are only measuring speed at one specific spot in the airflow, and as your simulations show, the velocity can be very different just a few mm away. There is a reason most MAF sensors are behind a mesh of some sort, it's not to keep debris out, it's to help smooth the airflow as it passes. Most MAF screens are actually tiny tunnels, a mm or so long.
Blowing in the air should not be the same as the outlets demanding air. There is a pressure differential created at the intakes of the rotors. I may be wrong, but when you blow the air in, the density of the air will also be different. You should redo the simulation with the source at atmospheric pressure and the intakes at a lower pressure. You will see a change in CFD, and that is what you have to optimize.
You need to keep the anemometer in the same location for the 2 different output sizes. Even if the FT2 and CFM is the same, you’ll get different velocity readings by measuring in the center of 2 different shapes.
would also want to calibrate each blower to the same output
For something that is "puling" from a plenum does the CFD really matter?
Really ready interesting and very informative. Can't believe how different and what changes flow so much
Always a blessing when rob drops new videos.
14:47 You know what else is MASSIVE?
Your mom
Bro ruined the comment section
Stop. Just stop.
The 12 rotor 😎
LOOOOOOOW TAAAAAPER FAAAAADE
I think you have to calculate flow to the different ports based on when they open. All ports are not open at the same time. Also, the intake will be under boost and will flow based on the path of least resistance (open intake port), not in succession and not all at the same time. If you were doing a naturally aspirated intake, then the measurements you took would apply, but still only to the intake ports that were open simultaneously.
I use tools like this in hvac for balancing. There is some math required since your typically getting ft per minute then you multiply duct size.
Id extend the front of the plenum so the intake is a bit further out, gives the air time to fill out the plenum before going into the intake pipes
This test has little to do with reality. I designed the intake manifold. The main mistakes:
1.) The cylinders suck in the mixture
2.) They do it one by one
3.) The most important thing is that air has weight. The larger the turbine, the higher the pressure it pumps air with, the greater its weight. It is amazing to watch how the distribution of the gas flow changes when the turbine reaches the operating pressure. If at low loads, as a rule, the first cylinders receive more air if we are talking about an inline 6-cylinder engine, but at high loads, the last ones receive more air, due to the mass and energy of the gas. And if at low loads, due to the fact that the cylinders SUCK air, the disproportion is minimal, then at high gas consumption this can be 5-10-15%.
It would have been best to buy 12 lambda probes and 2 CAN controllers for this money. And make actual AFR. This was a waste of money and time.
It's mainly a Marketing video from his sponsors. I've noticed people don't make videos anymore because it's fun but because they have to according to contracts.
rob needs friends with actual knowledge, dude surrounded himself with simps and its just a bunch of whack "experimenting"
@@18_DriftBox 100% , this is what the internet and money does to your brain. Crackpot ideas.
if you use exhaust logic with the inake you cant use a boxy figgure start with a big tube like a collector and line that up in the front into 12 smaller tubes that way theres less turbulance and more directed airflow
Danke Ihnen Herr Dahm,
gutes Video, mit deutlichster indirekter Fragestellung.
Der Ansatz ist schon gut. Die in etwa Gleichflußfähigkeit des Luftverteilers ist eine gute Basis. Aber dies gilt nur an der Stelle wenn alle 12 Rotore an der Position Ladungswechsel stehen und die 12 Scheiben exakt Synchron laufen würden. Da bei dieser Maschine aber nur 4 Rotore gleichzeitig am Gleichflußpunkt stehen, ist es erforderlich den Test mit 8 geschloßenen Kanälen zu machen. Die 4 offenen dürfen dabei keine großen Unterschiede in der Durchflußmasse die Sekunde haben. Das gilt natürlich auch für die anderen beiden Gruppen die bei Weiterdrehen um 60° des Motors in diese Position des Ladungswechsel Gleichfluß kömmen. Der Abfluß könnte mit Pulsventielen versehen werden die das Laufen des Motors bis Nendrehzahl simulieren können. Dann währen auch die dynamischen Massestromumlenkungseffekte im Liefersystem in den Griff der Kompensation zu bekommen falls dies erforderlich sein würde.
Q·E·D· Reiner Markenfreund
von Michael Frithjof Müller.
Think you need inlets of port tracts curved towards the throttle body inside the plenum so they scoop air in order
The LS motor one of the reasons it does so good is because of its Cathedral ports because when the valve closes the are tumbles instead of stops
This guy is making me look at rotary’s at 55, very cool and love learning. Is Mazda the only major manufacturer using rotary?
My next vehicle I want to go 300 k with as least issues as possible.
measuring the resistance of the manifold you could do by measuring the consumed power of the two leaf blowers with and without the manifold connected and some changes to it
I'm reminded of the intake manifold of the BMW S62. That had a weird plenum thing full of intake runner pipes. That design of the box and pipe shape/design was to ensure proper flow to all cylinders.
Just a machinist’s opinion. For a motor that expensive, I would suggest sending things like the manifold out to get surface ground rather then flattening with a fly cutter. Get a much better surface finish quality, and more uniform finish.
There is no benefit in surface grinding a flange that uses a gasket. It just has to not leak. That's it. No benefits beyond that.
@@APEX.86 Correct flat is flat
I've researched decking heads a little and it seams like they like to fave the fly cut finish and I have not seen one pro using a surface grinder for a mirror finish.
LOL surface ground intake manifold LOL
Then it wouldn’t be a rob dahm channel.
G'Day Rob,,yes it make sence when you think about how the Blowers are shooting straight in for the front runners to run lean,,What you need to do is to make a restriction on all runners and allow the pressure to work on the flow,,
so ifin you reduce the out let side of the manifold,(make the holes smaller),(just for testing) will make it more like the engine is running, giving you some back pressure in manifold,This will even out the different flows you are getting from each runner,,Pressure like water will always find the easist root to go,,with restrictions you will get better flow chararistics,
Edit:
Now all you have to diecide is how many rotor are on the same stroke at the same time,this will determine which rotor will get how much of the total mix going in,
Even though you think you have to flow right,,some rotors may run lean depending on intake porting and where in the manifold it get the air from,
Seems like the leaf blower idea really worked well. Great idea!
But, and I could be way off base here... I just keep thinking of the throttle bodies. The leaf blowers create a nice column of air and I'm sure they help to establish a nice baseline to measure from. I can't imagine the part throttle air will respond in a way that compliments all your hard work. 🤔
Anyway, just a thought I had. I know you guys will knock it out of the park in the end 👍
Good morning Rob👍🏼
Should those turbos create a positive charge of air in the manifold which would solve your problem of low pressure in some runners and high in others? I could be wrong.
I did something vaguely similar with an evaporative ducted airconditioning system in my house. One duct was not getting much air. I mounted a vane internally to the dropper to deflect air to it, and suddenly it was getting the lion's share of the air. I had to reduce the vane size substantially to even it out.
Neat!
Wouldn't you want high pressure air sitting as still as possible in the manifold, so it is available to go any direction (to the open port)? Could you make an upper plenum with larger openings for front ports that decrease in size for the rear ports?
I feel like your looking at airflow in the computer models. but if your intake manifold is under pressure like it should be once the turbos are running. I feel like once it’s under pressure because of back pressure. It will force the air into those first couple intakes that were not getting flow.
What about extending the front of the plenum and make the air go further after the throttle body to get in the intake plenum runners?
Being in the hvac industry specifically in the sheet metal fab and installation for over 45 years, and having to prove to young engineers what they draw on paper, and what according to theory works and doesn't work
I'd say if you built z equally progressive set of curved blades into every intake opening then you should get equal flow if the air flows smoothly along your plenum.
But this requires that you have true radius turns entering the plenum to eliminate the swirl that's causing the first few intake openings to be bypassed by your flow.
But remember to step up each time you make a curved blade that has equal margine of straight flat at the beginning and ending of each louver to allow the air to enter smoothly, make it's way across the surface of the radius of the heel of the louver, and again slide across a short flat section as it enters the opening into head this will eliminate largest majority of the turbulence you will have had.
I advise using smoke to verify your not introducing massive amounts of turbulence from your plenum into the head ports by using clear pipe attached to the plenum instead of the head itself to verify this and measure your air being pumped into your plenum, and measure the air flow entering each port to see how much static loss you have to allow you to make adjustments aa needed till true equal flow is reached and maximum flow is reached as well
The airflow needs to slow down as it enters the manifold. Push those throttle bodies away further and extend the manifold and or put a divider between the two sides. That should take care of most of your issues.
cool rob but it will work difficult due to a vac from the routers
My thoughts as well
No routers here, only rotors.
Rob, you should do some research on rally style dual plenum intake manifolds, they’re designed to promote even airflow even at high boost levels. Basically it’s just a tapered plenum connected to a log style manifold through a slot, kind of counter intuitive but it works better than ITBs on boosted applications.
LOVE THIS BUILD, KEEP IT GOING.
You’re going to have to make it so the throttle bodies blades’ axis are 90 degrees of the new manifold directing blades, because the throttle body blades are kinda going to give the same effect already
Probably should get a machinist to do that for you. The ridges are from you not turning the x feed handle smoothly like a powerfeed would do. You also have your tool hanging out way to far which causes vibration and the bad finish you are getting. Push your tool back into the holder, speed up your spindle, slow down your cut feed rate and take shallower cuts.
The best power band is a wide one! No one is talking about the reflected intake pulses inside the manifold when the pressure isn't positive. The best way to test an intake manifold in on a running engine under all conditions. It's a game of compromises. Print the manifold. Test. Change. Compare. Repeat. Then make it durable (aluminum)!
You may need to test at different inlet air speed. There always a potential that the devider behave differently at different air flow rate.
You really should go do a machine shop course, you'd benefit alot because you know the things you want to be able to do and you pay attention enough to ask the right questions...
Hey Rob, I'm no rotary expert by any means but I am a retire mechanical and automotive engineer and I think you may be over looking something. Starting with the setup maybe it's the camera angle but at 7mins 45secs the blowers look level BUT the intake does not, the runners that are getting the most air look like they are in a different section of the air stream and the plenum design itself I think is also contributing to the problem because it slopes down towards the back which will increase the air speed to the back runners due to the venturi effect, maybe it's me but I think these things need to be looked into especially the plenum design, it need to have a more universal and volumetric shape and design. I hope you get what I mean mate, maybe I've got it all wrong. Seeya Rob............from Australia.
Rob you can take that boring bar and carefully bend it downwards in a vise just a hair and it will clear the bottom of your boring head.. I do that with the cheap bars the boring heads come with. Just make sure you bend it the right way lol
That fly cutter had me squinting
It could take years to work out all the air flow bugs !!! But what about a slight hour glass restriction in center ???
Rember Necola Testlas flow restrictor,filter ???
That manifold flange is pretty thin. High likelihood it warps again. Might be a good idea to go to a thicker flange and maybe even gusseting to give the whole assembly some more rigidity.
i would be concerned about the definite swirling that the airflow from the leaf blowers has impacting your results, i would re test with some form of 3d printed laminar flow filters, think like a tight honeycomb filled tube about 3 inches long
Have you tried swapping the leaf blowers between sides? Just in case they aren't outputting exactly the same amount of airflow.
Whenever Rob ends his videos like this, I'm stuck. I just stare for a few minutes, not sure what to do.
would the airflow to each cylinder change under boosted conditions? i feel like all the accumulated pressurized air in the manifold would just disperse evenly since the manifold is under pressure.
Using a boring head as a fly cutter 🤣
Not as odd as you think. I used to have a special boring head that was designed to face parts also, you held the 'adjuster' ring with an arm and it made the tool grow in diameter whilst cutting. It was probably so you can face a part like a cylinder barrel on a jig borer.
It’s not stupid if it works 💁🏻
@@MrMaaaske95 It worked well enough for DIY in a hurry, but if you are paying a machinist and you see something like this don't go back. Not only is the surface finish terrible, it's bad for tooling longevity.
Yeah true. But I think the problem already starts with the fixture. I looks like the main flange is only supported by the intake runners which are in no way stiff enough to machine a truly flat surface
@@MrMaaaske95 Wont need to be a "truly flat surface" as it has gaskets that can fill imperfections.