Probably will not get any responses but here goes. I run a 598 bbc with 12^ profiler heads and went 4.43 in my 13 American. I run a Terminator on alky. Wondering if anyone else runs the 12* stuff on alky Terminator. I’d like to ask you a few question about EGT readings after a pass. I was 996* and thinking I’m about 50-75* to fat.
Thanks in advance

Did you try knocking 4 pill sizes out of it and seeing what happens? The tune up used on several 632 with 12 degree i know of, is 92-100 pill and 39 nozzles usually. Most of those guys seemed to like 30-32 degrees of timing.

quote:

Originally posted by 329L:
Did you try knocking 4 pill sizes out of it and seeing what happens? The tune up used on several 632 with 12 degree i know of, is 92-100 pill and 39 nozzles usually. Most of those guys seemed to like 30-32 degrees of timing.

I assume this is a #1 pump tuneup?

My conventional 632 tune is 'fatter' than this, but I'm using a 0 1/2 black pump.

I have a #1 pump 39 nozzles and a 96 return pill. On cyl 1 I’m 996*. I pulled the 96 out and put a 102 return in it to see what it does
Thanks

I used to run that combo, but on a 665". I don't monitor egts, just plugs and o2's as a reference. In Denver, I was running the 1 pump, 39 nozzles, and a 98 main if memory serves me. At sea level I was running the same setup but with a 74 main to get enough fuel in it, and it wanted 36* of timing as well.......

Your question really can't be answered here. My suggestion to you is to listen to the motor via the time slips! Too many variables involved. I assume you have a single cast 4 barrel intake and not a sheet metal intake (manifolds can easily cause and lean cylinders),,, either way your tune up could be ok but you're reading a cylinder that is rich or the calibration is off or placement on the tube etc.

See where it runs the best and that's your number.

I had a way more humble BBC, but did want to offer EGT’s, be it actually trend data or a peak reading device are worthless for finding the optimal tune up. Adding real time wideband O2 trend data is more helpful but not in the way you may hope. There isn’t an ideal lambda reading for quickest or most consistent runs, but 0.85 lambda is a worthy target. From that point, make adjustments yo the tune up and see how the WB O2 behaves relative to the time slip.
It can take months to find a happy spot, but once you find it, the WB O2 will be the first place to look if a run is off and track conditions or weather can’t explain it.
PS It is my opinion that a fatter tune up may not be as fast, but it will win more rounds as a more consistent engine. Good luck Vern

Thanks Everyone