RE: GO .25 Breakin in (heat cycle) F-UP!
Depends on the track, but if its a drag race i would of though the .21 are faster then the .25's and .28's (if all cars where geared the same) as the .21 rev more, but the .25's/.28's have more torque and would be better out of the corners.
Yup the .21 screams, the 7 port sounds just like a formula 1 car and i cant run it in the street its way to loud lol, even doing a few half throttle runs with the 5 Port it was screaming, i will do a quick vid tonight when im over the car park !