RE: Help W/ Tuning info for Rossi .40 FISE engine
I have run one of my Rossi's on a full pipe. Didn't get much over 17on a 9/7 apc but didn't put much effort in to tuning it. With a Rossi tuned muffler or a performance specialties short tuned muffler I was able to get into the mid to high 18s with a 9/6 apc. The Rossi tuned muffler that comes with the engine is a little long for going much higher and might not unload all it can get in the air. The performance specialties will unload better. I would think a full pipe should get to 19. This is all on 15% nitro with what ever shims are necessary for the extra nitro. Probably about .003 to .008 more than what is there. Generally if you try to run it with more than 5% as it comes from the factory the motor will get angry at you and show it.
Denis