I've have seen, and understand, the arguments between 87 and 93. Has anyone who owns a SG used it to monitor timing? I'm thinking of getting one to check out diff octanes and see.

 

im thinking the timing wouldnt change.. i dont think the ecu detects the octane of fuel but it changes timing if knocking it detected due to lower quality gas.. only 87 is required for our cars so i think 93 octane wouldnt change the timing.. but the ecu wants to run the highest possible timing though without knocking so its still possible in some situations there will be a difference in timing on 87 vs 93

 

"Theoretically" the ecu would EVENTUALLY change the timing.

Hp increase of maybe 5, after several tanks....

If I wasn't turbo and needing 93 I would check it for u.

 

I'm not going in thinking that the ecu would up the timing for 93, because I think it may be setup for max timing on 87. I just wonder if there aren't certain times where the knock sensor may kick in that you do not know about, when it would not on 93. Its a WAG, but I like experimenting :D

 

I used to hear some top end knock (like one hit) with my old drift spec exhaust. I blame the gas.

 

What Im seeing, is when the auto gets in 4th, and Im running around 48-50, and try and accelerate, there seems to be less power before the downshift on 87. I wonder if there is some knock when its lugging and that is the reason, I may just not hear it. Im currently doing testing on MPG of 87 vs 93. Ive already tested 87 E-10 gas vs no ethanol, and that was a 1.6 mpg increase by dropping E-10.