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 Stall Speed for the Summit 2802 Cam
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Two Feathers

30 Posts

Posted - 06 Jun 2014 :  08:15:09 AM  Show Profile  Reply with Quote
I will be buying a torque converter soon to match the 2802 summit cam I have. I was thinking a 2500 stall should do, but some say 2700-3000. What do yall think?

1970 Pontiac GTO, Atoll Blue, 400, TH400, 3.73 Safe T Track

Indian Spirit

643 Posts

Posted - 06 Jun 2014 :  10:57:43 AM  Show Profile  Reply with Quote
Now the following is from my own personal experiences. I do not claim to be a stall converter expert. So, if anybody has different opinions on the subject than me, that's fine.

I have found that most converter makers exaggerate the stall speed of their converters quite a bit. If confronted with this, they say that the advertised stall speed is a flash stall speed based on a big block engine. That's a bunch of bologna ! Most of the 12 inch converters advertised to stall at 2600 rpm won't stall anywhere close to that. Most are probably below 2000, and only very slightly above a stone stock 13" ! If yours goes 3000, great !

It's my experience that to get a converter that really stalls above 2000 rpm, it must be 10 inches in diameter. The 10" converter in my 455 bracket car will power brake to 2000 rpm and no more. So, to cut a good light, I jack it up to 2000 on the footbrake, and leave on the last yellow.

So, I would hesitate to buy anything bigger than a 10", if I really needed OVER 2000 rpm stall to get the car moving. Anybody who knows of a brand of 12" that will really stall 2600 rpm, please post that info here. It should help somebody here.

If you look up some real racing converters, you'll notice that most are either 9 or 8 inch. I bought a 9" for our E/SA '68 Bird. It worked exactly as advertised. You could powerbrake it to 3000 rpm with the 400 engine. TJ drove it and won lots of races with it.

After we started running bracket, with 455's, we ran stock 13" converters, so we could leave the line from an idle and still cut a good light, leaving on the last yellow. This was possible because of using Rhoads lifters with a RA4 grind cam.


But, if you got a 400 in a heavy street car, you need to get the rpm up, to get a better launch, because the 400 has much less low end torque than our 455's had. I bought a B&M "Holeshot" way back yonder. It was a complete waste of money. I could not tell a bit of difference in it and a stone stocker.

Edited by - bigD on 06 Jun 2014 11:32:28 AM
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Blued and Painted

3505 Posts

Posted - 06 Jun 2014 :  12:26:33 PM  Show Profile  Reply with Quote
Rule of thumb is the low end of the cam's power range PLUS 500 RPM's
Summit says the basic opperating range is 2200-5500. Sooo by rule, 2700 would be optimum.
BUT many converter stall speeds are figured using small block chevy torque and power numbers.
If so, a good running 400 with more built in low end torque could easily push the stall speed of the converter UP another 100 rpm's. Key words -good running 400-. Well tuned carburetor and distributor on a well matched combo.
-- I think your on the right track with 2500 stall.--

Continental can build a custom converter for a few bucks more. Im running one.
Fill out there spec sheet with what you know then see what they say. It dont cost a dime.

Bull Nose Formula/ 461/ Q-Jet/
TH400/ 3.08 8.5 / R44TS.

Edited by - Blued and Painted on 06 Jun 2014 12:28:34 PM
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Crazy Horse

1442 Posts

Posted - 06 Jul 2014 :  07:19:22 AM  Show Profile  Reply with Quote
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