Does any one know how much thrust is lost with a Bifurcated pipe? I fly at 5400 ft and lose about 20% power at 60 deg. I first flew my Avonds F-15 (kit built) yesterday with his pipe and it took the whole 600ft paved runway to get off, than I had to keep it flat tell got some speed. I have a JC P80SE in it, rated at 22# at sea level. The plane is 25# dry. Thanks George