I was running a SMC 2C 7.4 lipo and a 13.5BL with a roll out of 43.33 thats a 87 spur and a 20 tooth pinion I found I had a lot of speed but I did not have the body to hold the car down in the sweepers Not sure what the fast guys ran but they were so fast it was scary. check out
www.irocc.ca and look under pancars for a lot more info
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