I start with some history I've had with the two, tghe first was the proto and the second is the production, the first one I had before Sept. and got it ready for the Nitrohouse Labor Day Race at Revelation, yes they are tight engines so they do need some time of conservative running before you really dunck on it and the engine a tune when up to temp engine so don't try to do your tunning on the bench. At start the engines run cold and need some revs to bring up the temps so you can set the idle if too cold it will stall. I ran JP-2,3 and 4 and they resopnded the way the pipes were designed, the 2 was still my best option, the engine sounds like an on-road engine when up to speed, it has smooth bottom end and a good floing top speed, with 1.0 springs and our 10013 shoes they got me what I needed to run good to make the a-main, my fuel run time I was putting was 7 min just to be safe but have 9min on a tank to the end and I also still was on the conservative side of tunning since the Sept heat was tipping under and over the 100 degree mark, that engine managed to egt me 4th place in a 40minute race with no flame outs but my drive train was skipping a gear. It was very impressive for an engine with the dollar price that it's going for.
When the production one came in we have run it hard and I mean I have done a short break-in and then wide open, it still reponds the same waqy when cold and when up to temp but it seemed like I need to take a shim out to be on the better end so nothing major in the tunning process after the shim was taken out, the shim is like .023 and didn't have a .01 around which i think is the better way for fine tunning the production runs just like the proto and we were not to veer away or do any major changes to the engines, hot plugs seem to work the best even in high temps, I ran Picco plugs but any thing will work but I feel like what ever you start with you may want to stick to that since the bottom will form after heat cycle. I had run Picco engines strong and was very reluctant about running the engine but now has my full attion and will be my race engine for 2010.