Try 25 initial, 35 at WOT and then layer in 6 degrees of vacuum advance on top of that. You'll have to drive it to find out what it really wants but 31 total isn't enough with the Indy heads. Those will want at least 35 and maybe more. Idle timing is the easiest to sort out since you can just change the timing in your driveway and see what works the best. With a big cam you usually want as much timing at idle as possible.
Does your system have a built in start retard? Holley EFI always starts the engine at 15 degrees and then it pops up to the idle timing. Check to see what yours does.
Thanks Andy! I had a feeling the timing was to low, the engine has more to give.
I will try it. Do you have any guess of at what rpm i should give it full advance? From what i have read many brings it in pretty early.
Start with 3500 for full advance and try it. You'll just have to play around with it since it all depends on how heavy the car is, what the gear ratio is, etc. No way to give you an answer without knowing all the details so just try it and adjust as you need to.
Thanks Andy! I know its difficult to give an answer of a timing curve, now i have a starting point. My car is quite heavy, its a Chrysler 300 -64 2 door hard top. The cars weight is 4189 lbs, rear wheels 275/60-15 with a cicumference of 27.99", gear ratio in the rear 3.55:1, its a 8 3/4 with a eaton true trac helical diff, 3" drive shaft with 3150 universal joint front/back, 727 tci streetfighter with a reverse manual valve body, 9.5" 3000 stall custom built converter. I have eaton custom made super stock leaf springs, adjustable pinion snubber and i actually have good traction with this car, when i hit the throttle the car sits in the back and throw away this heavy car like a bullet. The engine answers amazing but i have had a feeling that i have been a little to careful with the timing.
