Pump Gas

Hey guys I'm thinking about rebuilding my ex this winter and I was going to put a new piston in it and was wondering what is the highest compression I can get and still be able to run pump gas?

11:1, 92 octane minimum.

i know plenty of people do it, but i won't run anything less than 100 octane in my 11:1. the pumps around me have either 91 or 93. I have read many times that people are able to run premium with 11:1, but i just won't risk it.

Long ago my 11:1 tried running on 93 octane and would still get a little ping, so I went to 100 aviation fuel, wasn't much differance in price. Later I would just add some turbo boost each fill up. Then later I started getting the 93 at a Sunoco station, the 2 strokers told me they really liked it. I have had no pinging or knocking last couple years.

thanks guys! if I put some octane boost in it will that be enough instead of having to buy race fuel?

torco is the only octane boost that actually works.

I ran as well as my buddies 92 octane in our 400s for years, never an issue.

I've been running a JE 11:1 416cc for about 2 years now I guess. some times I've ran the cheapest thing at the pump (87) for just riding around the house. and 93 for when I go on longer riding trips. and for the few xc races I do I just got some 110 racing fuel at the station in town ($8/gal).

Yep I run 11-1 with a xr gasket, 93 all the time, never a issue.

Have used 87-93 in my 11:1 and never had deto probs.

ive ran 87 in my 11:1 440 never had any ping but now i run 92/100 mix