I also think porting exhaust to either early or wider, but not later timing as well as polishing is the key to more power. RX-8 has massive intake compared to before but exhaust is the real restriction. Especially the middle iron where two rotors exhaust comes to meet and push back against each other. I think a sleeve or header plate with divider between the two to extend the factory tiny divider will go very far
You should see the ports on my renny.. CNC ported.. has some good overlap. The exhaust port has that shelf cleaned up too, but the beauty is that the exhaust ports were extended far lower than stock.. opens probably the same time as that peripheral port does and as you said, closes much later. 👍🏼 not to mention my intake ports.. massive.
I can see the benefit of extending the exhaust ports lower, but modifying the intake ports I’ve yet to see anything truly beneficial and don’t really see the point in it. Small peak HP is there, but midrange takes a hit which just means the car struggles more in the area it’s usually at under normal conditions. As far as racing “especially endurance racing” the biggest difference seen between ported vs stock Renesis engines are longevity. The ported engines just don’t last. This is why I opted for just cleaning up the cast defects and carbon catchers and nothing more and it’s wonderful and is considerably quicker than stock
Nate Rist I agree on the intake ports.. I got them done because why not? Lol I love my renny.. it thinks it can hahah I will be supercharging it soon 👍🏼
You correctly show the no-overlap when you talk about the side port. When you talk about the overlap with the peripheral port you say it is opening when actually it is beginning to close to that face of the rotor. It was already fully open when the side port was closed. Otherwise the peripheral port is opening, but opening to the next face of the rotor and “that’s how much the intake is open” does not correlate to that face. I do appreciate the video and being able to see what goes on inside the Renesis.
Depends on HOW porting is done. At low RPM only primary port is open. So if you don't port the primary port, you won't lose low end torque. If you open the exhaust too early you will lose low end torque but gain top end. If you don't port towards the housing walls, you won't have overlap. If you cut down on the dam wall on primary port, the amount it gets trimmed will affect the fuel mixture vs air flow. It's about HOW you port it. So port the secondary and aux ports for max air flow, port the primary for trimming the dam wall and smoother flow into the chamber. Port the exhaust for wider and smoother flow without early opening for power without losing torque.
Anything beyond stock shape ports degrade performance. No matter what you do with porting they will never be as good as stock ports. Minor top end gain isn’t worth it when it degrades performance throughout the rest of your rev range and porting down on the exhaust port will cause HP loss (this is true for and NA rotary and why it’s always recommended to only port up, but the Renesis is as far up as it can really go, so nothing can really be done beyond that). The only form of “porting” that’s truly beneficial is leaving the port shapes as they are, but smoothing our the carbon catchers and removing cast defects as well as rounding off the sharp edges.
Apparently doing any kind of research is as much of a taboo as it's ever been with them or they treat you like the bad guy for telling them the truth instead of what they want to hear. It's pretty sad
A renesis swap would be perfect, but it’s a very involved swap that can take a lot of time, so just building and streetporting your current engine would be a much easier route. I would highly suggest getting a set of turbo plates as ported 4 port NAs will always be capable of more power than a ported 6 port
@@MrMeoow91 pretty much, 2 of the 6 ports open just shy of 4k rpm. He’s saying the turbo 4 port irons would be better because they can be ported more. The 6 port irons have less meat to grind off around the intake ports. I have a gsl-se and I think I’ma streetport my 6 port when I rebuild, but I’m not shooting for enough power to necessitate 4port irons.
@@MrMeoow91 All 13Bs make 120+HP. A street port will put you on the higher end of that range, but you’ll need a tune to take advantage of the new ports
I have ported engine, that basicly did already more then many rx8 engines. And it produces little more power, and have better fuel economy than non ported, but... i have tuned ecu.
I own a rx8 with a half Bridgeported and turbocharged. It’s doesn’t really sound like brap and more like brop brop brop. sound doesn’t as solid like 13b RE Bcs of the exhaust port are different. But it’s still “brap”. 1 more thing make different I guess might Bcs of renesis are using E throttle and RE are not. E throttle will automatically rise up the throttle when it sensed the “unstable” overlapped idling so make it sound funny. there’s goes spent extra money for standalone ecu again. But overall the 13B renesis still amazing and having lot of fun with it.
The build you’re planning has been tried many times and almost always results in failure. Blocking the side ports would be preferable, but there isn’t a reliable way to do it (welds will hold for a bit, but will crack and fail due to inconsistent expansion of different metals). If I were you I’d ditch the idea of 5 exhaust ports and just port down on the side ports to allow more heat to escape sooner. NA that might lead to power loss, but in a turbo application you’ll make that back up and more. Also clearance the side seals to .006-.008 and it should do fine
@@NateRist Welding the iron plate sounds (as you mentioned) prone to failure. Keeping all side ports full open will reduce the exhaust velocity, so, turbo will spool slow. But what about keeping side ports opened but using a very small tubing (only for the side ports)? Iron plate will still reliable plus exhaust might flow well. I'm just trying to investage as much as possible. Your idea about porting sounds interesting, how ever I'm still worried about the Renesis reliabitliy passing the 400whp mark. Thanks for info... Great channel
@@josezuma If reliable 400whp is what you're after i'd probably just bite the bullet and go with either an REW or other older 4 port peripheral exhaust only setup and use your modified RX-8 rotating assembly paired with a streetport and you should see that along with great torque and response on low boost.
I run 4 port plates with ported exhaust ports and devcon in the intake port, stock rx8 housings with no exhaust port and a 48mm peripheral port, custom exhaust with one resinator and a muffler, gilmer belt kit and a 48mm ida. Check my vid out
I’m not a fan of it either. The series 2 system was a great improvement, but still doesn’t do anything for the area between the intake ports and oil injectors.
@@NateRist for me the whole fuel/oil injection system on rotaries seems off. I've always wondered why not just inject the fuel directly after the intake is closed off by the rotor and have the oiling done in between intake and exhaust ports. Also always though the exhaust should have been handled by a port on the housing rather than the irons.
Ty ty ty about time some body speaks up
Old 13b: brap brap brap
13b renesis: mmmmmmmmmmmmmmmmmmmmmmmmmmm
Old 13b goes mmmmmmm factory to
renesis: [washing machine at 1000rpm intensifies]
You have to port both engines as well it doesn’t come from the factory brapping
"Not like subaru bad" Nice explanation.
I also think porting exhaust to either early or wider, but not later timing as well as polishing is the key to more power. RX-8 has massive intake compared to before but exhaust is the real restriction. Especially the middle iron where two rotors exhaust comes to meet and push back against each other.
I think a sleeve or header plate with divider between the two to extend the factory tiny divider will go very far
Classes in session today's topic Port timing!!! Sick info video bro!
You should see the ports on my renny.. CNC ported.. has some good overlap. The exhaust port has that shelf cleaned up too, but the beauty is that the exhaust ports were extended far lower than stock.. opens probably the same time as that peripheral port does and as you said, closes much later. 👍🏼 not to mention my intake ports.. massive.
I can see the benefit of extending the exhaust ports lower, but modifying the intake ports I’ve yet to see anything truly beneficial and don’t really see the point in it. Small peak HP is there, but midrange takes a hit which just means the car struggles more in the area it’s usually at under normal conditions. As far as racing “especially endurance racing” the biggest difference seen between ported vs stock Renesis engines are longevity. The ported engines just don’t last. This is why I opted for just cleaning up the cast defects and carbon catchers and nothing more and it’s wonderful and is considerably quicker than stock
Nate Rist I agree on the intake ports.. I got them done because why not? Lol I love my renny.. it thinks it can hahah I will be supercharging it soon 👍🏼
Thanks for the great video Nate......
You correctly show the no-overlap when you talk about the side port. When you talk about the overlap with the peripheral port you say it is opening when actually it is beginning to close to that face of the rotor. It was already fully open when the side port was closed. Otherwise the peripheral port is opening, but opening to the next face of the rotor and “that’s how much the intake is open” does not correlate to that face. I do appreciate the video and being able to see what goes on inside the Renesis.
Depends on HOW porting is done. At low RPM only primary port is open. So if you don't port the primary port, you won't lose low end torque.
If you open the exhaust too early you will lose low end torque but gain top end.
If you don't port towards the housing walls, you won't have overlap.
If you cut down on the dam wall on primary port, the amount it gets trimmed will affect the fuel mixture vs air flow.
It's about HOW you port it.
So port the secondary and aux ports for max air flow, port the primary for trimming the dam wall and smoother flow into the chamber. Port the exhaust for wider and smoother flow without early opening for power without losing torque.
Anything beyond stock shape ports degrade performance. No matter what you do with porting they will never be as good as stock ports. Minor top end gain isn’t worth it when it degrades performance throughout the rest of your rev range and porting down on the exhaust port will cause HP loss (this is true for and NA rotary and why it’s always recommended to only port up, but the Renesis is as far up as it can really go, so nothing can really be done beyond that). The only form of “porting” that’s truly beneficial is leaving the port shapes as they are, but smoothing our the carbon catchers and removing cast defects as well as rounding off the sharp edges.
@@NateRist you will have to explain larger ports on 4 port engines with more torque.
But Nate, saying the word brap is so much fun! Please don't take it away from us!
it's funny how "Rx8 owners" have morphed from Rx7 guys to new kids that don;'t know much... my 2 cents
Apparently doing any kind of research is as much of a taboo as it's ever been with them or they treat you like the bad guy for telling them the truth instead of what they want to hear. It's pretty sad
I just bought an RX7 S4 NA, thinking of a Renesis swap...but nahhhh...properly just Street Port when rebuild comes.
A renesis swap would be perfect, but it’s a very involved swap that can take a lot of time, so just building and streetporting your current engine would be a much easier route. I would highly suggest getting a set of turbo plates as ported 4 port NAs will always be capable of more power than a ported 6 port
@@NateRist Isn’t 6 ports Mazda’s Vtec for rotary right?
@@MrMeoow91 pretty much, 2 of the 6 ports open just shy of 4k rpm. He’s saying the turbo 4 port irons would be better because they can be ported more. The 6 port irons have less meat to grind off around the intake ports. I have a gsl-se and I think I’ma streetport my 6 port when I rebuild, but I’m not shooting for enough power to necessitate 4port irons.
@@DJrainbizzles I am looking to hit 120-150hp at the wheel without any intake & exhaust mod. Not sure whether that is possible...
@@MrMeoow91 All 13Bs make 120+HP. A street port will put you on the higher end of that range, but you’ll need a tune to take advantage of the new ports
I have ported engine, that basicly did already more then many rx8 engines. And it produces little more power, and have better fuel economy than non ported, but... i have tuned ecu.
Hey bro, Messed with many of the 4 port renesis ? same story?
My 8 has some overlap now, as there’s a tiny bit of brap lol
I own a rx8 with a half Bridgeported and turbocharged. It’s doesn’t really sound like brap and more like brop brop brop. sound doesn’t as solid like 13b RE Bcs of the exhaust port are different. But it’s still “brap”. 1 more thing make different I guess might Bcs of renesis are using E throttle and RE are not. E throttle will automatically rise up the throttle when it sensed the “unstable” overlapped idling so make it sound funny. there’s goes spent extra money for standalone ecu again. But overall the 13B renesis still amazing and having lot of fun with it.
is it a multi-port exhaust hybrid?
No, those are just terrible and horribly unreliable
@@NateRist May I ask you why?
I'm currently building a hybrid Renesis turbocharged, do you recommened week all exhaust ports open or block side ports?
The build you’re planning has been tried many times and almost always results in failure. Blocking the side ports would be preferable, but there isn’t a reliable way to do it (welds will hold for a bit, but will crack and fail due to inconsistent expansion of different metals). If I were you I’d ditch the idea of 5 exhaust ports and just port down on the side ports to allow more heat to escape sooner. NA that might lead to power loss, but in a turbo application you’ll make that back up and more. Also clearance the side seals to .006-.008 and it should do fine
@@NateRist Welding the iron plate sounds (as you mentioned) prone to failure.
Keeping all side ports full open will reduce the exhaust velocity, so, turbo will spool slow.
But what about keeping side ports opened but using a very small tubing (only for the side ports)? Iron plate will still reliable plus exhaust might flow well.
I'm just trying to investage as much as possible.
Your idea about porting sounds interesting, how ever I'm still worried about the Renesis reliabitliy passing the 400whp mark.
Thanks for info... Great channel
@@josezuma If reliable 400whp is what you're after i'd probably just bite the bullet and go with either an REW or other older 4 port peripheral exhaust only setup and use your modified RX-8 rotating assembly paired with a streetport and you should see that along with great torque and response on low boost.
@@NateRist Sounds like a good idea. Going to check for some parts.
Just to close this topic , what were the failures you saw with the Renesis Hybrid?
@@NateRist Another RUclipsr built a race Renasis engine by using peripheral exhaust ports. It seemed to work great for mazdatrix.
Yes brap brap
I run 4 port plates with ported exhaust ports and devcon in the intake port, stock rx8 housings with no exhaust port and a 48mm peripheral port, custom exhaust with one resinator and a muffler, gilmer belt kit and a 48mm ida. Check my vid out
So peripheral intake with side exhaust ports. Sounds interesting
Where's your vid bro?? Doing the same atm
I'm an rx8 owner and I like it just the way it is couple bolt on and go want real nasty horsepower buy a Lamborghini lol
Brap elitists 😂
Am I the only person who looks at the Renesis and thinks the injection on it is done wrong?
I’m not a fan of it either. The series 2 system was a great improvement, but still doesn’t do anything for the area between the intake ports and oil injectors.
@@NateRist for me the whole fuel/oil injection system on rotaries seems off. I've always wondered why not just inject the fuel directly after the intake is closed off by the rotor and have the oiling done in between intake and exhaust ports. Also always though the exhaust should have been handled by a port on the housing rather than the irons.