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Discussion Starter #1
Ok, my basline was 10.35 @ 129. I had some problems with the converter, now I hopefully have corrected it. Even with a bad converter, my cam swap added .11 & 1.8mph. I also switched over to wilwoods (23lb reduction ans virtually no drag). The new converter is looser by 800rpm, which is closer to my peak tq of 6200.

If the new converter puts me back where at I was, I am expecting 10.20-10.25, but Saturday is the tale of the tape.

Predictions???
 

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What kind of power does your car make?

I have a 77 with a 383 pro-1 heads 11-1 with a small solid in it. On the engine dyno it made 485hp 480 tq. Peak tq came in a 4800rpm. My converter will only foot brake to 3200 rpm. I was thinking about getting a bigger converter like 4200-4500rpm. My 60ft is only 1.85-1,90 with et streets. It pulls 114mph. but seems slugish up top. I have a roller set up to put in it .605 lift. Just wondering what kind of converter you have also.

Thanks
Duane
 

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For best ET's, I believe convention wisdom is to have a converter that flashes at peak tq. So a 4800 converter should wake things up. Where it foot brakes is almost meaningless.. Its more a function of brake holding power. The most accurate test is to get in high gear from a slow roll then stab it. Your notice the rpm will get to a certain rpm and level off. Where that instant stopping point is, will be your flash rpm. 383's are notorious for flat tq curves, if you look at your dyno sheet, you probably will see nearly the same tq for 800 or so rpm. If there is not much difference between where your current flash rpm rpm is and the peak tq, there is little to be had. Said another way.. If you flash at 4300 rpm, and your motor makes 470lbs of tq, then changing to a higher stall speed will not net you much improvement. However if you tq at that flash level is 50-60lbs lower, you have the opportunity to gain substantially.

My setup- My engine makes pk tq at 5700, the converter I ran flashed at 5100, I knew it was short. . I just changed converters, going to test it Sat. This one is supposed to flash 800 rpm higher, I'll post my results.

The tell tale HP gauge is MPH, tuning to the best mph is usually best. Your 114 mph is consistent with a 11:60-11:70 car. So the corresponding 60ft should be in the 1.60-1.65 range.
 
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