Peripheral Port Renesis dyno's
#1
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Peripheral Port Renesis dyno's
This is just what it sounds like. This is a Renesis that has had peripheral ports cut into it. The side intake ports are no longer used. The side exhaust port configuration is retained. We've been curious about it. Here it is.
The results are very interesting. As predicted, power does go up. However it isn't anywhere near what a peripheral intake and exhaust engines can do. It is interesting to note how much the powerband changes between 19" in length and 22" in length. Look at what rpm it makes more power than the stock engine.
http://www.rotaryeng.net/RX8PPB-Stock-RX8.jpg
http://www.rotaryeng.net/RX8PP264a-Stock-RX8.jpg
Here's how they built it:
http://www.rotaryeng.net/Welded-steel-p-port.html
The results are very interesting. As predicted, power does go up. However it isn't anywhere near what a peripheral intake and exhaust engines can do. It is interesting to note how much the powerband changes between 19" in length and 22" in length. Look at what rpm it makes more power than the stock engine.
http://www.rotaryeng.net/RX8PPB-Stock-RX8.jpg
http://www.rotaryeng.net/RX8PP264a-Stock-RX8.jpg
Here's how they built it:
http://www.rotaryeng.net/Welded-steel-p-port.html
#3
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It should be pointed out that the most powerful periperpheral ported engines make their peak power up over 9K so this may actually not be that bad.
The 19" runner graph shows power being greater than stock above 6100 rpm. That's pretty high. If you look at the extreme left though it implies more power below 5000 rpm as well. If the tuning trend could be extended down lower, it would probably make more power between about 3500-5000 rpm as well. That is assuming that these runs didn't just start at 5K but rather the graph does.
The 19" runner graph shows power being greater than stock above 6100 rpm. That's pretty high. If you look at the extreme left though it implies more power below 5000 rpm as well. If the tuning trend could be extended down lower, it would probably make more power between about 3500-5000 rpm as well. That is assuming that these runs didn't just start at 5K but rather the graph does.
#4
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Here's a dyno of a conventional all peripheral port (non Renesis) engine with 24.5" long runners. A shorter runner setup should be more powerful. This shows a peak power level of about 245 hp which is more than the shorter (22") intake runner p-port Renesis.
http://www.rotaryeng.net/Weber58-24....yno-curve2.jpg
This implies that the peripheral exhaust port is still superior when used with a peripheral intake port. I'd tend to agree as you need to have similar timing characteristics between intake and exhaust port to get full potential.
http://www.rotaryeng.net/Weber58-24....yno-curve2.jpg
This implies that the peripheral exhaust port is still superior when used with a peripheral intake port. I'd tend to agree as you need to have similar timing characteristics between intake and exhaust port to get full potential.
#5
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Here it is on the dyno at Mazdatrix:
http://www.rotaryeng.net/Idle3.wmv
http://www.rotaryeng.net/Standoff3.wmv
http://www.rotaryeng.net/Idle3.wmv
http://www.rotaryeng.net/Standoff3.wmv
#10
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It's idling around 1300 rpm. Here in Texas your car needs to idle below 1000 rpm to pass inspection. This engine is also using a carb and not fuel injection so there is probably some power to be had and a lower idle that could be obtained.
#11
Destroying Threads
#12
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I'll just cut to the chase rather than play around; whomever prepared those first two sheets wasn't even smart enough to make sure that the torque and h.p. lines intersected at 5,252 rpms for the engine they were supposed to be measuring. In the last sheet you posted the lines DO cross, as they are supposed to.
Actually they do cross at 5252. The stock dyno lines are hand drawn in for rough reference only.
#14
dang... hp goes up but so does tq. for someone who isn't rolling in cash, this is well worth it if u already have the engine out or replacing one... but to pay for labor for all that mmm~
#16
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Good luck trying to make this work with the stock ecu. I guess it could be done. You would need a new intake manifold though. It's not something I'd do to my engine. I'm still convinced that the all side port rotary is the perfect street combination.
#18
How are you still convinced??? It makes very little power when modified in N/A form (compared to previous gen) and it doesn't run any better than the old 13b's.
![Lol](https://www.rx8club.com/images/smilies/lol.gif)
#19
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Look at it again. It doesn't have a peripheral port exhaust. It's all side port exhaust. Only the intake ports are peripheral.
Keep in mind this engine isn't for a car. It's for an airplane. He only cares about what it does at 1 particular rpm and doesn't need a big powerband.
#20
Finally Boosted!!!!!!!
I always thought the exhaust ports were more of a restriction than the intake ports? I understand that there is power to be had by improving the intake ports but couldn't we see a larger increase in power from exhaust porting?
Forgive me as I am not well versed in porting and its pros and cons...
Forgive me as I am not well versed in porting and its pros and cons...
#22
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iTrader: (25)
Look at it again. It doesn't have a peripheral port exhaust. It's all side port exhaust. Only the intake ports are peripheral.
Keep in mind this engine isn't for a car. It's for an airplane. He only cares about what it does at 1 particular rpm and doesn't need a big powerband.
Keep in mind this engine isn't for a car. It's for an airplane. He only cares about what it does at 1 particular rpm and doesn't need a big powerband.
sideways oval would be better than a round port IMO, harder to make though
I know who he is and what he's doing, not impressive at all considering those are flywheel #s
![Dunno](https://www.rx8club.com/images/smilies/dunno.gif)
#23
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Those peak power numbers aren't impressive if all you are looking at is the peak. Look at what rpm those peaks occur at though compared to engines that make more power and it really isn't bad.
#24
#25
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How many other peripheral intake, side exhaust port engines have you seen? I stated earlier that it was lower in power compared to an all p-port engine. It should be. The exhaust port timing is all wrong in relation to the intake timing.