I'm running the hatori header and short pipe with Cool Power 30%. Around 8000 is a good RPM. Anything about 8200 or so wont make the noise requirements. I've seen some guys getting 8300-8400 with this setup. Mine peaked out at about 8200, but I'm running it now about 7900 and no power problems for the AMA Masters sequence, and I've flown all the way up to F-11 with my 10lb 8 oz plane and flown in some crazy heat here in SW Texas...

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