I've got a hyper 7 and don't know if I should go .21, or higher. I have the original hyper .21 but was wonderind if a .28 with taller gearing would be faster. And if it is faster will it hurt the diffs in the long run. I'm "racing" but not "RACING" (we made our own track in a lot nearby[>:]). I'm not new to the hobby, but I am new to nitro. Any help would be greatly appreciated.

A bigger engine won't rev as much as a .21 engine.
S get yourself a 16bell and a .21 engine and you will be fine.

ive got a samuarai infinity .28 in my pbs, yes it has more power and speed, and my diffs and drive shafts are taking it really well. nelly everyone in my club run oversize engines and there has been no probs with any of there cars yet, the one prob is, its not race legal at most clubs

Thanks for the replies, but what about the taller gearing with the larger engine?

cant c why not, the bigger engine has more power to turn a taller gear ratio, might even do that myself

I can say from experience that taller gearing with a larger engine does NOT work as well as a screaming .21. I know that it should work in theory, but in practice is doesn't. You'll just loose bottom end and the top won't be there soon enough to make a difference. The engine can't rev fast enough to make the taller gearing do what you're hoping it will. I've run the SW .26, the O.S. VG30 and a couple of others and neither worked well, regardless of the gearing.

I run at a small track, in a small club, but they are all nuts and die hards. Most of the new comers show up with some sort of "big" engine, but soon learn that the .21s dominate. The rev more quickly, have a better top end, and get better runtimes.

i will agree that the run time is not as good with the big blocks, but i still recon they have more balls. a couple of the guys at the track had a drag race down the straight, both cars were the same except one had a .21 rb s7 ($370au) and one had a .28 samurai 528 ($150au) and the .28 pulled away from the .21
and as for .21s reving harder than .28 thats not true, the hyper 8 port engine revs to 38000rpm, where as the team infinity samuari 528 revs to 43000rpm. well thats what the web sites say anyway
http://www.team-infinityrc.com/produ...p_id=1&lang=EN
http://www.ofna.com/eng-hyper21-8port.html
have a look 4 your self

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