stall change effects on MPH and rear gear ratio

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monzadude
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stall change effects on MPH and rear gear ratio

Post by monzadude » Sun Apr 03, 2016 3:50 pm

I'm having higher stall converter built for my car and am wondering if I'll need to change my rear gear-set.

My car weighs 3100 lbs, 28" x 9" slicks, 5.83 gears, TH 350(no trans brake) and my current 9.5" converter stalls close to 3200 RPM and I can foot brake to 23-2400.
Engine is 321cid (3.1" x 4.06") that I shift at 7800.
I work at a converter shop and am building an 8" that the boss assures me will go 5 - 5500 flash stall. Obviously that will
improve my 60's and ET's but I'm trying to figure out what my trap RPM's will be, which could possibly force a gear change.

Maybe I'm making this too complicated in my head, but it seems to me that if I launch 3000 RPM's higher then I'll go through the traps that much higher..?....

Thanks in advance for any help!

Mike
Just "little" smallblock Monza
321 cid NA, 3100 lb, 28x9 ET Streets
6.9 @ 101 in the 1/8 & 11.0 @ 127 in the 1/4
Still tuning!!!

rfoll
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Re: stall change effects on MPH and rear gear ratio

Post by rfoll » Tue Apr 12, 2016 9:01 pm

I recently changed from a 9" 4400 to a 8" 5100 converter, and the finish line rpm is not much more than 100 rpm more. This stuff can be addressed when the converter is assembled. Stall speed is not the only characteristic designed into a race converter.
So much to do, so little time...

Biteme
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Re: stall change effects on MPH and rear gear ratio

Post by Biteme » Fri Jun 10, 2016 6:55 am

It shouldn't change your finish line rpm by much at all.
Build the converter with tight clearances and it'll mph well.
Higher stall is kind of like dumping the clutch at a higher rpm.

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