Originally Posted by
airraptor
The irvine has low transfers and boost ports allowing the exhaust to raised up to a good number while at the same time keeping the blow down in the good range.
So what mods did you do to the exhaust and what blow down numbers did you give the Irvine?
With converted car engines one get much better (higher) blown down numbers without any mods needed to the liner, and tuned pipes will really make a difference there.
You only get that in airplane engine if you by the ones that are timed for tuned pipes. Novarossi will offer both types/timing for most of their engines, and they are very well priced nowadays. The build quality is also well above the OS airplane engines. It seem OS are only making an effort on their car engines...