Steve, i have a 637 big block Chevy that’s setup the same way you have here, but not atomized. We to had hours and hours of trying stuff and making pull after pull. Went from the procharger speced cam to a custom screw blower cam and it made it worse, switch back to a custom turbo cam picked up power and boost down low, but failed to make more then the og cam. What we found was the (3500hp rated procharger speced) valve springs were floating up top but you couldn’t tell on the data log. It only showed it laying over up top in the log. We went to a tighter valve spring,
The hardest part of a big engine is trying to feed it, a 396/427 will scream with the same factory heads that make a 496 502 540 a stump puller, that's why we run smaller displacement engines when having fun, cheaper to build, that's why 427 is my favorite engine, and doesn't build enough tq to blow the tires off, but screaming at 6600 RPMs is fun on good factory parts
It's gonna have a blower on it so intake runner thength really doesn't matter as the whole manifold is pressurised in the same volume of intake. Runner length matters a lot on Na engines not so much boosted engines
@noxious89123 huh. Flowing? The air is under pressure it doesn't care about flow. The air is under pressure hard up against the intake valve before the valve opens its already taken the path to valve whilst valve is in closed position.
@@LeeSchofield-gr4mq Like I said it's a shot in the dark but you usually see boosted engines with short intake runners due to the fact it's a pressurized system so it doesn't matter. However being ran without boost a fast throttle blip would likely benefit from a reserve of air space in a larger intake as apposed to having to pull it threw the throttle body from the atmosphere. That many cubes pulling threw a throttle body on strictly atmospheric pressure will likely have different air/fuel ratios as it goes past the intake ports in sequential order front to back. I'm no engine builder, just a dude on the internet but hey it makes sense to me😀😀
Fuel & Timing? Like I'm questioning an engine guru. Gotta find that 903 sweet spot. Just like a woman. See what tickles her fancy, then tickle a bit more!!!🎉
Considering you're filling a 113 CU IN cylinder, that intake runner looks tiny in this video. Your limitation is the jet RPM, so the build is quite valid. In terms of trying to make big HP numbers N/A, the intake runner volume is small.
Love to see more intake on that thing. Twin throttle deal, maybe twin 4500’s for na dyno? I think its starved for air. But what is the intake vacuum doing?
You need to make a real change if there’s room in there to do it. Widen up the lobe centers or add intake duration on the closing side. 5 degrees minimum. This is more the Big Block Chevys sand box here, A Hemi over 8000 is really just eating the keeper grooves and making the valve stems look like shit.
Couple of things, I want the top ring gap to be smaller than the second ring, don't want the top ring to float, second of all, the TQ and HP numbers are not going to make sense on a hemi style engine, they don't follow basic rules, bore vs stroke doesn't matter, just over all displacement, I don't know much about big engines, I do run a 14 and 15 liter engines but never over 1800 rpm and we use turbos to feed them, just kidding CUMMINS
Im thinking because of the combination chamber design being hemispherical the pistons are dome shaped to fill in the hemisphere. Only having 1 spark plug per cylinder its not getting enough flame propergation quick enough to completely burn the fuel either side of the dome. In blown hemi drag cars they always have 2 magnetos and 2 spark plugs per cylinder. Im not sure on bote size of the drag blown hemi but there not 903 ci. So the bore on this engine is probably 5 to 5.5 inches. Nearly 1 inch diameter bigger than blown hemi drag motor's. I think your getting closer to sorting it out with msd 600 ignition so maybe thete something in what im saying? Id bite the bullet rip the heads off drill n tap 2nd spark plug location then look at your numbers sky rocket. Lets face it 1200 hp from 903 ci. Na is only 1.2 hp per cubic inch. Thats not much from any race motor s standard.
This is why real World testing rules. Paperwork has always punched me in the face. It gives you a good direction to go but fluid Dynamics without a supercomputer and bites you every time. before I even knew what a flow bench was I was making things that essentially were just that playing around with my 2 stroke porting.
Steve, so the camshaft isn't the best. When you add boost, does the different camshafts still make a difference? Maybe the current camshaft on boost will produce more hp than others.
When we put a big cam in an engine you get a lot of fuel standoff on a n/a engine.With a plenum intake you may be recycling that fuel and screwing your afr numbers.?
@@thomashodis5740 Yeye I know, drooling anyway still love to some one with money build something like that , proline makes awsome motors iv seen mountain motor prostocks *800 ish to 1001 cubes N/A *Id just like to see what kinda power can be made probs no double but still.
@WeswesO - I saw the video on this motor. He's still figuring out the cam. It's for a jet boat. They want 2500 hp on pump gas. So he's figuring everything out before he throws boost at it. He's already making around 1100 hp, and he hasn't figured the cam out yet. It's interesting to see what he can get it to make n/a . But yes, proline makes some bad ass motors. And it has some insanely fast cars. I like that Steve is custom manufacturing ls stuff, but fixing the short comings of the ls at the same time.
@thomashodis5740 Thanks. That makes sense now.I was wondering why he was running this NA and happy with a thousand HP. How could Steve build an engine like that only to make 1000 ? I was wondering what was going on. I'm assuming there are some videos on this engine ? I'll have to have a look. Get up to speed on this engine.
Just watched the entire larger video. I actually like seeing your thought process on video. Love your videos. We recently dynoed a 4 cylinder turbo on mustang dyno and made an estimated 854 on crank and 727whp, but during the process fought an old distributor and coil and just that change out to a new setup gave us 85 whp, which I had been suspecting possible issues at the track. Love the seeing the process! Keep it up!
I wish I could afford one of your engines 😩 I have a 8 second late model big tire ranger with a full tube chassis I built (perks of being a fabricator at a race shop) it currently has no engine due to the last one turning itself into a bunch of small pieces because I trusted a guy I shouldn’t have. lol love the videos man! If I ever get up enough dough I’ll be coming your way!
![Tee Grizzley - Blow for Blow (feat. J. Cole) [Official Video]](http://i.ytimg.com/vi/wNLN5xsx5dc/mqdefault.jpg)
Steve, i have a 637 big block Chevy that’s setup the same way you have here, but not atomized. We to had hours and hours of trying stuff and making pull after pull. Went from the procharger speced cam to a custom screw blower cam and it made it worse, switch back to a custom turbo cam picked up power and boost down low, but failed to make more then the og cam. What we found was the (3500hp rated procharger speced) valve springs were floating up top but you couldn’t tell on the data log. It only showed it laying over up top in the log. We went to a tighter valve spring,
UPVOTE THIS. The big cam could be laying over because the springs can't recover the distance quick enough.
Compression and fuel maybe with a sprinkle timing makes the power. Don't put any more air in it... Just reflect on what I said
Can't believe how awesome this turned out!
900 inches needs a LOT of cam.
Every time you post, it's a treat!
You are a liberal and a bot. cant be trusted.
valve float? or is it an intake system restriction?
@@fry.master agree on the intake restriction, feeding a lot of cubes.
Breathing through a straw, cam doesn't matter till it can breath.
The hardest part of a big engine is trying to feed it, a 396/427 will scream with the same factory heads that make a 496 502 540 a stump puller, that's why we run smaller displacement engines when having fun, cheaper to build, that's why 427 is my favorite engine, and doesn't build enough tq to blow the tires off, but screaming at 6600 RPMs is fun on good factory parts
Tons of ways to control power instead of building a weaker
Engine
On purpose. Suspension tuning, timing ( grid) dump valves.
Shot in the dark here but i wonder if the short intake runners are a issue. Seems like 900ci would would enjoy a little more intake volume.
Short runners generally like rpm
It's gonna have a blower on it so intake runner thength really doesn't matter as the whole manifold is pressurised in the same volume of intake. Runner length matters a lot on Na engines not so much boosted engines
@@LeeSchofield-gr4mq Of course it still matters. A better flowing intake means you can make the sme power with less boost.
@noxious89123 huh. Flowing? The air is under pressure it doesn't care about flow. The air is under pressure hard up against the intake valve before the valve opens its already taken the path to valve whilst valve is in closed position.
@@LeeSchofield-gr4mq Like I said it's a shot in the dark but you usually see boosted engines with short intake runners due to the fact it's a pressurized system so it doesn't matter. However being ran without boost a fast throttle blip would likely benefit from a reserve of air space in a larger intake as apposed to having to pull it threw the throttle body from the atmosphere. That many cubes pulling threw a throttle body on strictly atmospheric pressure will likely have different air/fuel ratios as it goes past the intake ports in sequential order front to back. I'm no engine builder, just a dude on the internet but hey it makes sense to me😀😀
Fuel & Timing? Like I'm questioning an engine guru. Gotta find that 903 sweet spot. Just like a woman. See what tickles her fancy, then tickle a bit more!!!🎉
Always Great stuff !!
I must have missed the debut episode, covering the origin of the 903 motor build. This is no aftermarket Chevy. Did you make this engine from billet?
I am also curious why, under development, it was so important to have tool steet cams made for an engine that wouldn't see 6500?
Lift is good around 980, been watching.
Considering you're filling a 113 CU IN cylinder, that intake runner looks tiny in this video. Your limitation is the jet RPM, so the build is quite valid. In terms of trying to make big HP numbers N/A, the intake runner volume is small.
Maybe do a video on DYNAMIC COMPRESSION
Love to see more intake on that thing. Twin throttle deal, maybe twin 4500’s for na dyno? I think its starved for air. But what is the intake vacuum doing?
You need to make a real change if there’s room in there to do it. Widen up the lobe centers or add intake duration on the closing side. 5 degrees minimum. This is more the Big Block Chevys sand box here, A Hemi over 8000 is really just eating the keeper grooves and making the valve stems look like shit.
Bigger cam, still lays over at the top. Wouldn't that indicate a flow restriction upstream of the valve?
Couple of things, I want the top ring gap to be smaller than the second ring, don't want the top ring to float, second of all, the TQ and HP numbers are not going to make sense on a hemi style engine, they don't follow basic rules, bore vs stroke doesn't matter, just over all displacement, I don't know much about big engines, I do run a 14 and 15 liter engines but never over 1800 rpm and we use turbos to feed them, just kidding CUMMINS
Im thinking because of the combination chamber design being hemispherical the pistons are dome shaped to fill in the hemisphere. Only having 1 spark plug per cylinder its not getting enough flame propergation quick enough to completely burn the fuel either side of the dome. In blown hemi drag cars they always have 2 magnetos and 2 spark plugs per cylinder. Im not sure on bote size of the drag blown hemi but there not 903 ci. So the bore on this engine is probably 5 to 5.5 inches. Nearly 1 inch diameter bigger than blown hemi drag motor's. I think your getting closer to sorting it out with msd 600 ignition so maybe thete something in what im saying? Id bite the bullet rip the heads off drill n tap 2nd spark plug location then look at your numbers sky rocket. Lets face it 1200 hp from 903 ci. Na is only 1.2 hp per cubic inch. Thats not much from any race motor s standard.
This is why real World testing rules. Paperwork has always punched me in the face. It gives you a good direction to go but fluid Dynamics without a supercomputer and bites you every time. before I even knew what a flow bench was I was making things that essentially were just that playing around with my 2 stroke porting.
Steve, so the camshaft isn't the best. When you add boost, does the different camshafts still make a difference? Maybe the current camshaft on boost will produce more hp than others.
Restriction of the throttle body a culprit???
All depends on the lift the grind duration everything
Doesn't it matter how the cam was ground.. meaning to delight peak tq & hp at a certain rpm??
A lot of engine for 1500 horsepower, you can get that out of an LS easy
If spark isn't the issue, wouldn't it limit it to the intake since it's the back half of the motor is having issues?
When we put a big cam in an engine you get a lot of fuel standoff on a n/a engine.With a plenum intake you may be recycling that fuel and screwing your afr numbers.?
Does a nice bellmouth in front of throttle increase power? The set up now is , imho , not optimal and hurting flow into plenum the higher rpm range.
I wonder if its valve flote? Do they still make see through valve covers so you could look at it with a slow motion camera
What does this use for oil filtering Steve?
Put a much larger throttle body!!!
More cam and maybe more valve spring
Needs more duration say 440 @ 50
14.3 liters that is nuts getting in to semi engine size
Also- loved seeing that last powerband. Can't wait for the next video with the supercharger! Finally on the homestretch!
Does it have any vacuum?
Eh just 1200 hp first pull 😮
Only if it has sufficient fuel!
Id like to see a 1000 cube hemi, built like the Proline one that already makes 5k hp
Yeah this is a n/a pump gas motor. Not at all comparable to prolines motor.
@@thomashodis5740 Yeye I know, drooling anyway still love to some one with money build something like that , proline makes awsome motors iv seen mountain motor prostocks *800 ish to 1001 cubes N/A *Id just like to see what kinda power can be made probs no double but still.
@WeswesO - I saw the video on this motor. He's still figuring out the cam. It's for a jet boat. They want 2500 hp on pump gas. So he's figuring everything out before he throws boost at it. He's already making around 1100 hp, and he hasn't figured the cam out yet. It's interesting to see what he can get it to make n/a . But yes, proline makes some bad ass motors. And it has some insanely fast cars. I like that Steve is custom manufacturing ls stuff, but fixing the short comings of the ls at the same time.
@thomashodis5740 Thanks. That makes sense now.I was wondering why he was running this NA and happy with a thousand HP. How could Steve build an engine like that only to make 1000 ? I was wondering what was going on. I'm assuming there are some videos on this engine ? I'll have to have a look. Get up to speed on this engine.
They use too run a billet 670 twin turbo combo in the early 2000s they made good power
cylinder heads are done
More throttle body?
Wow, so cool
Boost the snot out of it
Can you put a even bigger cam profile in it to gain more?
Looks like it needs even larger camshaft 😅❤
Really awesome job. If I had enough money. I would build a 1,100 ci. Hemi big block with EFI and dual overhead cam shafts.
Large Displacement laughs at large cam duration 😂
I remember the old billet 670
Twin turbo engines from the early 2000s haven’t seen that combo in a while actually
No, more power basically everywhere with more cam. Bigger cam more power, but more risk to valavetrain and rpm limitations. Also durability hit.
Just watched the entire larger video. I actually like seeing your thought process on video. Love your videos. We recently dynoed a 4 cylinder turbo on mustang dyno and made an estimated 854 on crank and 727whp, but during the process fought an old distributor and coil and just that change out to a new setup gave us 85 whp, which I had been suspecting possible issues at the track. Love the seeing the process! Keep it up!
This thing has 3 times the displacement of my Coyote.
Maybe it's still too small?? What are the cam specs that pat musi runs in his 900+ci motors? Yes they're nitrous but must be in the same range?
Slowly getting this beast figured out, keep chipping away at it.
Smaller works it's what the motor likes send it
You have to feed those big cans.
still not stalling the head flow
That thing Is a beast
Victory
😊😊😊❤❤❤
I wish I could afford one of your engines 😩 I have a 8 second late model big tire ranger with a full tube chassis I built (perks of being a fabricator at a race shop) it currently has no engine due to the last one turning itself into a bunch of small pieces because I trusted a guy I shouldn’t have. lol love the videos man! If I ever get up enough dough I’ll be coming your way!
One day, I hope to be able to have you build one of your amazing motors for me for a "street" car.