Detonation/pinging

[70rolla]

Hey I have problem a rather bad one my motor is detonating almost constantly the motor is
A
16v Jap bigport
It has pretty high comp
Running bt pistons a Trd 0.8mm head gasket and a bit milled of the head only a bit
It's running a stock Jap ecu

I run 98 octane fuel it was ok for a while but has gotten bad
I do need to get it on a dyno but what can I do to stop the detonating
Add octane booster? Retard the timing?

[Deeken]

Probably both man, high comp = increased combustion temps which = need either more fuel/less advance/higher octane.

[70XIN]

Octane booster is crap. That setup should comfortably run at stock ignition timing (~15 degrees). I wouldn't be suprised if it's running alot more than that.

If it isn't that, then you may have got a nasty batch of fuel. Never rule this out.

[70rolla]

Yer the tank is running low I'm going to swap with a clean tank and fill it with fresh 98 I want to get the distributor checked out and get the timing checked too

[timbo]

Run a bit of kero with the next lot of fuel to clean up anything in your fuel system. Worked wonders for me.