Im getting detonation and trying to figure out why. my setup is ls/vtec ctr pistions/itr cams. compression 11:8 car is tuned but it was tuned on 94 octane gas from sunoco and since they dont sell it anymore ive been using 93. Dont know if that is the problem. But im detonating at low and high rpms. I checked the plugs to make sure thats what it was and sure enough the white dots r present. Any info is much appreciated. Thanx.

 

was it detonating when you used 94?

 

no not at all and thats why im thinkin it may be because i switched and just need to be retuned.

 

if u didnt hear it at 94 then going to 93 shouldnt have made that huge of a difference, well not that major at low and high rpm.
check your fuel pressure maybe your pressure reg is messed up

depending on how they tuned it, it is possible they didnt give u a conservative tune so the change from 94 to 93 made a big difference
get it tuned again

 

hmm that does sound pretty strange maybe that 1 octane point makes it detonate now.

 

yeah maybe im stumped. I didn't get the engine tuned either so I wouldnt know if it was conservative or not. I was thinkin of maybe changing the plugs for now till I can get some cash for a retune.

 

I thought detonation signs on spark plugs were BLACK dots...

 

I don't think so Im pretty sure its white but I may be mistaken.