Which Gas Type is most sufficient?

[Lukeidiot]

87 89, or 93? which should I use with my 01 400ex. Its pretty much stock besides for the sprockets.

[400eXr1d3rZ]

87 works fine until you get a high compression piston.

[Lukeidiot]

Originally posted by 400eXr1d3rZ
87 works fine until you get a high compression piston.
Thats what i've been running :D

[Lukeidiot]

My friend however just got a big bore kit, would it make a difference if he used 87?

[NacsMXer]

As long as the kit is still the stock compression (9:1) you can run 87. I have never heard of a big bore kit with that compression ratio though. If it is 10:1 or 11:1 I would run premium in it. Anything higher than that you want to run high octane race fuel.

[400eXr1d3rZ]

Originally posted by NacsMXer
As long as the kit is still the stock compression (9:1) you can run 87. I have never heard of a big bore kit with that compression ratio though. If it is 10:1 or 11:1 I would run premium in it. Anything higher than that you want to run high octane race fuel.

Depends on your situation you could either need to run race fuel for a 11:1 piston, if you do get an 11:1 piston, I suggest you run on a half mix, better to be safe than sorry ;)

I have a 10.8:1 compression piston, and cometic gaskets, I'm running no base gasket (high temp silicon sealed) and on a hot day, every-once in a while I hear a ping on heavy acceleration and at idle, I went to the local mechanic shop and bought me some high octane fuel, I throw a cup of it in my gas tank (one cup, I fill my tank with 93 octane fuel) on a hot day and the pinging goes away.