My ski 2000 sj is pretty much modded and the engine is freshly rebuilt, it has ada head with 35 cc domes , the cylinder is bored to 85 mm and uses wiseco pistons, dual 46 buckshots, cylinder is ported for racing, fp dry pipe type 4 high rev version, atp total loss system, atp waterbox, msd water injection system, solas 13/17 with stock pump, work grate, blowsion tubbies 2. my ski runs pretty good, ifeel like it can rip your arms, pull very very hard on the bottom end. BUT! when I ran with my friend 2010 sj with only b pipe and everything in his ski is all STOCK except the pipe, and he only changed the main jets and pilot jets bigger to 75 and 135. his ski and mine has the same speed, HOW COULD THAT BE?? my ski ran rich to be safe at first but I tried to lean the carbs and got only slightly better top end than his. eventhough his ski doesn't pull hard as mine, but from mid to top is pretty much the same speed when we ran on straight line. I feel a lot depressed now haha. anyway, many people told me that my prop is too small for the engine so I just ordered a new big hub cutback 14/19. hopefully it'll make much difference. any suggestions to make mine faster? I don't know what else to mod now 
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