RV-7/whirlwind prop/Ram Air

Anyone have an RV7 with Whirlwind 200Rv prop and Rod Bower Ram Air combination? Specifically any prop clearance problems with the ram air scoop that is at the front of the lower cowl?

Yes....but I also have a Sam James extended cowl and AFP injection. My clearance problems were internal, where the Bower airbox hit the cowling. I think the AFP injection unit pushes things forward a bit, so had to open up the cowl a touch.

That's my config...

Its tight, but thats a good thing. See my pics under finished rv7. The scoop was a bit of work.

tanker95 said:

Anyone have an RV7 with Whirlwind 200Rv prop and Rod Bower Ram Air combination? Specifically any prop clearance problems with the ram air scoop that is at the front of the lower cowl?

Click to expand...

back to intake scoop to prop clearance question

I am fabbing my intake scoop for an AFP FM200 servo mounted on a cold air sump with a Bowers ram air can. The intake scoop is attached to a short SJ cowl and the scoop will be modular so I can remove it exclusive of the lower cowl. The front of the intake ring is even with the cowl spinner ring... same plane. consequently, the very front lip of the intake ring will be 1/4" from the trailing edge of the prop when the prop is at its full course stop limits. I am using a Hartzell BA prop and will not be using a prop spacer.

Anyone else's intake and cowling arranged like this? My questions are:

1. does the prop ever see full course pitch stops in routine ops?
2. is there a min gap requirement to not "foul" the air flow into the servo intake?
3. Will I see 10+knots gain because of the insane amount of ram air I will be pushing into the engine with the resultant prop air slamming effect? (humor me and just say yes to make me feel better...)