Quote:
Originally Posted by Adger Smith
Stay away from the 1.12 Reaction number
When you have 2 gear spreads use the one with the number the farthest away from 1.00.
I would look at the 2.16 -1.45 C-1 .73
If you can use just a little more starting line ratio the second gear drop will pull the car up to speed quicker. The 3 speed will get you in hi gear a little farther down the track with the 3 speed than the PG. It will also make your converter react like it is tighter.
1st..second.hi.% drop1-2...% drop2-1...Shift....Fall.....Shift2-3.....Fall RPM
2.16 1.45.1..... -32.9%..-31.0%....... 7200........4833.......7200........4966
I just guessed at the shift point.
Guess you have a 1.98 PG low..
The PG has a 49.5 % drop from low to high a 7200 RPM shift will bring the mechanical RPM back to 3636
See the difference in hang time on the converter. You are using second gear ratio to move the car instead of converter. I hope this helps
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It's a 1.69 x 5.29 final crossing 1/8 converter slipping 5% 7450rpms. I ran it to the 1000 ft once 8000 rpms 9.69 @ 1/4 coasting 116 mph 10 x 28 M/T bias. This with a spragless converter 90% hum, 2875 bar, 78 deg
I think with a 3 speed it might dip in the 9.30's as is, in premium conditions 3250lbs sbc factory condition 69 Nova on a bias tire n/a.
I'm trying to find the best approach for second gear for a 4.56 final. 1.30 to 1.40
For the small tire, I think around 8.9 starting line ratio is good, even if I went to a radial tire, one tenth quicker typically.
It did help, thanks for your input I'll study that to comprehend your approach. This is just a ol car I drove to work, then street raced, then Super Pro bracket raced and now just hot rodding for fun 30 years later.
