I got my pacer going really fast and thought i would share what i did. First I drilled the intake to the max. I think its like 13mm or so. Changed exhaust to a puch boss pipe. Widened exhaust a lot. Widened intake a little. Shaved head. Kept stock 12:14 dell but rejetted to 60. I went from 22 mph to about 35 or more with loads of power. Its the 1 speed piston port morini engine (M1 i think). The clutch seems to slip a lot though. Other than that its sick.