Is there some reason you cant use a street ported engine combined with a peripheral port, which would have a valve so the PPorts only opened at high RPM's? That way you would have minimal overlap and high intake velocity at lower RPMs, but then still be able to flow lots of air at high RPM's.

Sorry if this has been discussed before or I'm throwing out something way off base or impractical, but I was thinking...

So, rotary experts, what do you think?

 

Well.......

I'm building one


it's just because most people don't really want a small PP, and after you get to a certain size, the side-ports become kinda pointless. i'm only using a 1" - 1 1/4" PP, so I get a bit more leeway

 

but why not create a large PP but have a valve so it only opens at high RPM?

 

because that valve would have to be perfectly flush with the rotor housing to ensure there would be no overlap - and that would be stupidly expensive to make practical

 

lol

 

I have built a PP/streetported turbo motor for a customer 1 year ago. It had 30mm D-port PP holes and a good flowing streetport. The exhaust was a very large monster port. It was fed with 98 octane unleaded and controlled by a Haltech E6K with 6 660cc injectors. The engine was never dynoed but the T-2 -87 best ET was a slow 12.57s -122.4mph Car weight 2900lbs. The boost was set at 18psi think it made nearly 500 flywheelhp. It was indeed streetable shift point 8500rpm, but when he began revving beyond 9000 rpm the engine let go becaussse of lean conditions. Next year we shall dyno the engine!

 

the factory raced engines like that in the late 60's

 

Mine's goin to be carbs though - i can't afford all that injection stuff. So i'm going to be sacrificing power in the name of costs