DA-150, KS 1080 pipes and stock Flex headers, Biela 30-12 three blade.
Static RPM: 5400 Hot
Same engine with solid headers and 1090 pipes and the Biela 29-12 3-blade
Static RPM: 5850-5900 Hot.
I found that I prefer the KS1080 pipes over the 1090's because of the much smoother midrange throttle response, while not really losing very much on the top end power. Everyone wants the BIG numbers up top, but the plane definitely was easier to fly with the 1080's and smoother throttle curve.
I'll be happy to trade straight across for some 1080's if anyone has a set they want to get rid of
