Originally Posted by John Schafer

I broke-in and raced 2 new GRPs last weekend. A tuned .28 and a Powerhouse .21 . On the .21 I ran a JP-1 (powerhouse recommended) a 6mm restrictor and, a MC-9 plug. On the tuned .28 I ran a MSR 1005 with a 6mm restrictor and, a O.S. P-3 plug. Both engines ran, tuned and idled flawlessly on Sidewinder 30%/12%. Both engines also ran in the 230 degree range. I was not overly impressed in the power department, but then again they don't have much fuel through them and they had 6mm restrictors. Also both engines, buggy and truggy were getting about 8.5 minuted per tank. I think the pipe choice and the engines still being tight had a little effect on the runtime and also running temps.

I will be trying different pipes next time, which may be several months before I get the chance to race again. Someone said a few posts earlier that these engines were "cold blooded". I disagree. Compared to my Werks engines the GRP's are great...