HI

I have a problem you guys might be able to help with!!!!! I have Zenoha G38 in a 1/3 G.P. Pitts Special it starts on runs great with the cowl off the plane and max's out at 7600 rpm with a 18x8 prop and pulls the plane nicely through the air. But when i install the cowl I loose about 500 rpm and it has a tendency to want to die when the plane hit take off speed. this is what i have donne so far


I have opened the cowl up right in from of the carb wich made it it better during take off ( it dosent want to die on take off any more) But still not getting top end power

I tryed a valosity stack and it has made no diffrence

i have baffled the entrance to the cowle and it has not fixed it iether

some has mentioned to me it might be a presure problem in the cowl???????? i dont know how to address that if that is the case i have about 4 time the exit of air as in take


any ideas would be helpfull



Thanks