Pump Gas

[hondaracer44]

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?

[CJM]

11:1, 92 octane minimum.

[2001400exrida]

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.

[DragonGunner]

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.

[hondaracer44]

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

[CJM]

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.

[400man]

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).

[Thumpin440ex]

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

[Zakradu398]

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

[Stroisch400ex]

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

[DragonGunner]

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.



Ya Torco is what I got, good stuff.

[2001400exrida]

There's plenty of other good ones as well, Torco isn't the only one but torco is among 3 or 4 quality octane boosters that actually work. One of them being toluene and xylene as well as the lucas oil racing octane boost. maxima high test is also another good one. 1 oz. of the high test will raise 1 gallon by 4 pts.

Anything you see in walmart will generally be junk, but any of the proven race names will increase octane just pay attention to the product and what it actually claims. Blendzall also makes a good one.