Modded 82 update
Fired up the 82 that I modded for 11.75:1 compression last year. This engine also has a Gary custom muffler and a 100 carb. I finally got the new ring broke in fully and everything went to crap. The engine was fussy on the needles, rpm wandering all over and running overly rich in the mid range. Swapped out the plug with new and no joy. Swapped out the 100 carb for the original 82 carb and all is good again!
Once the ring broke in fully the engine didn't need or want all the extra fuel supplied by the 100 carb I guess.
With 15% nitro this engine has a very wide window of adjustment on the hsn. It's probably borderline over compressed on 15%. Even though I can't hear any predetonation or see any deformation of the plug element it sure is acting that way. I may go ahead and shim the cylinder up .005" as I mentioned last year.
APC 13x8
9650 peak
2000 idle
APC 14x6 (sport)
9450 peak
1900 idle
APC 14x6 (pattern)
9750 peak
1900 idle
Last edited by Glowgeek; 04-02-2020 at 05:29 AM.