i am thinkin about having my topend redone because im a little low on power and i think while im at it i will put in a high compression piston. does this mod require race gas or can i use 93 octane pump gas. also how about the reliability will this wear the enigine out quicker. thanks.

Don't know about reliability, but higher compression usually requires higher octane (i.e. higher ping index) so that you won't have pre-ignition - read this link.

AV-
WOW AWSOME site thanx, where do you find sites like that BTW?

I can't take credit for this one - a while back there were discussions about "avgas" (no not my gas! ), in that thread member SUnruh posted that link - I learned quite a bit about fuel, compression, ignition, etc. from reading those pages! BTW, Eric Gorr has been working with motors for quite a while...

If your in need of a rebuild, the higher compression wiseco is a great choice. The engine will run just fine on the pump stuff, even farm gas .Normally burn premium 93. Have tried race gas, but it did require rejetting(richer). Seat of the pants noticable, but egad, the cost.. Have ran Av 100 lots,and it works noticably, one main larger. I do not like to run anything for fuel that is not conveniently available. There just are not that many VP or Sunoco service stations in my area...

Hey running farm gas would be a great idea. What octane is it usually? I remember buying some a while ago for a lawn mower and it was about 20 cents/litre cheaper.

The only time I run the purple fuel is when I forget gas and get out to Bergerland....

I have the seizco 2mm over piston (13.5:1 ratio). It's got tons of umphhh, but when it stalls... good lord... your damn foot hurts for two days afterwards. I'd stay with the 12.7:1 ratio.