Quote:
Originally Posted by NoDOHC
I think that I misunderstand what a PP does for the Volumetric efficiency. I thought that they ran 125-130% VE at 9,000 RPM. My engine is making 102% VE at 7,700 RPM and making 160 WLb-ft (= 240Wlb-ft on a 20B) at 6500 rpm where it makes 98% VE.
I would expect the torque to be significantly better for an engine with better VE.
I also would have expected this engine to make about 8% higher torque/VE due to 9.7:1 vs 8.2:1 compression. This should put the torque output at 175 Wlb-ft / 100% VE for a 13B or 263 WLb-ft / 100% VE for a 20B. This is why I expected 280Wlb-ft out of it, I guessed 110% VE. Do you have a VE curve for that engine?
Your AFR is similar to mine, your timing is similar to mine (given the differences in Compression ratio).
This thread is scaring me, as I am beginning to worry that adding compression ratio adds enough flow resistance past the cusp in the housing to destroy any gains that are made by it (I have read that somewhere).
I will have to wait until spring to find out now (I will run my engine with 9.4:1 rotors instead of 8.2:1 rotors).
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Well honestly the 160rwtq is probably the highest I've seen from any n/a 13b. Short of a full p-port. After reviewing the setup, I do not know how it pulled it off. That exhaust is terrible in a high efficiency standpoint, and the correct resonance. The most torque I have made is 152rwtq on a 9.7:1 13b. But only after getting the exhaust in correct length. 135-140rwtq was with a off the shelf Rb header. Remember rotaries are not very efficient. 15% less is normal. I am half tempted to send you one of my headers and see what your car could do. The other half of me thinks the dyno wasnt calibrated correctly. lol. But in short its WAY different to get the 160rwtq at 6500 and getting 160rwtq at 10000. You have not considered frictional losses which go up exponentially with RPM. The engine is getting more friction, the water pump and alternator are getting more, the weight of everything takes more energy to spin, and the transmission friction is rising a bunch too. Then add into the fact air velocity is moving much faster, well you get the idea. Compression does not change HP alot on rotaries, you are correct. Lastly, I can tell you personally that the FC coils are great. There is not 30rwhp from a ignition upgrade. Feel free to PM me though, you are on a very right track for sure!