Hey all, just wondering what ignition timing you guys run, and what octane fuel you run along with it. I'm at 8 degrees now and running 87 octane but I wanna go to say, 10 and I want to see if anyone has to run 89 or 92. Stock 9.3:1 compression btw.

 

whats stock on an l98?

 

it's 6

 

you could be doing more harm then good,

TPI has a knock sensor, you won't here the knock, but the ECM will be retarding your timing

I run 94 octane all the time(canada) and have my base timing set to 8*
I'll still see alot of knock retard on a hot day as much as 11* at WOT

with your timing at 8* and running 87 its possible your sending your car in to low octane mode,
low octane mode is a less aggressive spark table when knock is sensed over an extended period of time,

which is accually worse,

really to stay out of low octane mode you should run 91 octane with 6* base timing

the real way to adjust your timing is with a custom prom

this is the spark advance table for a 91 L98, this is where you want to make adjustments based on load and rpm, you can isolate maximim spark at a given load and rpm, but to adjust you need a data logger of some kind,
thats how I know how much knock retard I'm gettting