WOW...... massive amounts of posts while i was at work .

ok, that time delay from the NV adjustment to the effect of that adjustment wouldn't really matter would it?.... i mean, you don't adjust the needle valve in mid flight. you're on the ground with an RPM gauge waiting for the RPMs to change ... waiting being the key word.... plus, i can wait a half a second for the flow change if it means making those changes is safer for someone prone to clumsiness, and the looks of the plane of better

ok, about the cowling i was thinking of building onto my trainer (after a while of flying it, just to have a test bed for the act of constructing one before i go ahead and do as i'm planning with my second plane).... air intake will be a 2 inch wooden dowl cut in half longways (to make 2 half circle yet long pieces), then carve out the middle to make something like a pipe. that would be about 1 and 3/4ths inches intake "surface area" (it's really anti-surface area since we're talking about gaps or cutouts ). the outlet would be a 1/2 inch gap between the bottom of the firewall and the bottom lip of the cowling..... with a 4 inch wide firewall that would mean 2" of outlet. not quite 150% (2" to 1 3/4" is about 114%) but def enough of a difference in surface area to cause the suction.

thanks for all of your time guys, and the great info

Rob