As of friday afternoon I set my base timing back to factory spec. I have a '91 RS w/ an L03 w/ Stock internals. Factory spec is 0 degrees with the ECM disconnected from the dist. So I set it back to what I can tell is the 0 degree-ish line on the tab. May be retarded a smidge, like 1 degree. It was around 12-13 degrees retarded when I first checked it, so I was initially shocked. The car runs nicely now, idling, operating temp, etc. but I can't tell any power difference. I only run 87 octane b/c that's all it needs, but am I missing something? It sounds a bit better at WOT and general driving (used to backfire a bit, but has stopped) but I figured it'd make a difference. Will my fuel mileage change? I was getting 24+ highway and 16-19 city before.

knowledge desired, thanks for any help
- wimbo

 

I bet it would be even happier with about 4-6* initial timing... Try it and see what happens. Fuel mileage should get a little bit better, power and drivebility will too.

 

i doubt you were getting 24+ MPG with your timing retarded like that if anything you probably would have got worse much worse... are you sure you didnt read that backwards as in the wrong side of the timing tab

 

Dude, don't question the math. Last year I avg. ~22 every tank, and my last trip to Detroit I got 27.9 MPG, doin 68-72 the whole way and absolutely NO WOT accels. I even checked my MPG after runnin at the local drag strip. Including the trip there and back I averaged 16 mpg.

I'll see if I can take a pic of the tab. it's kinda rusty but I'm pretty sure I got it right. The 0 degree mark should be in the "V" to the left (driver's) side of the vehicle, correct? W/ the right lighting I can make out faint #'s on the tab.