Mike,

Your a hard man, however I do agree with both the Mazdatrix and Powersport results and would expect their operating at optimum configuration and 100% VE.

 

The question in my mind will we all achieve this in our less than perfect installations - probably not.

 

I can't remember exactly but powersport was running two PP sizes, 38mm or 40mm early version and the later 44mm. I believe Bill Jepson is awaiting the results of a more recent 44mm dyno run. That 210hp may be the old 44mm HP numbers - can't remember exactly. Then again it may be the smaller inlet as they were running 6,000 for take-off RPM. A smaller PP will give greater inlet speeds reflecting in VE.

George ( down under)

George,

The 210 HP Powersport engine is the 38mm inlet. P-port of course. The key to their success is a very clean inlet tract. They also tuned for lower RPM by using a long inlet runner. The original Powersport engines were not intended to run over 7000 RPM. That doesn't mean that they couldn't, just that with the long intake pipe you weren't making any more horsepower. Steve tested the larger 44mm inlet. It is far greater on the flow bench, but we will be assembling the test 2 rotor after dynoing the new muffler to get a baseline on the older small port engine. The flow on the 44mm inlet was off the charts, but it must be tractable to be successful. Most decent P-port rotaries will calculate at slightly above 100% VE if based on the inlet diameter. The runner tuning really works when you have no valve to get in the way! Of course if you turbocharge the VE doesn't get better, but the engine doesn't care when being force fed.

Bill Jepson