Thread: Stall Size

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Small block?

3200# or over?

I'd say a stall speed rated at 2400 rpm is about the max you'd want to run.

Keep in mind that the converter is slipping until you exceed the stall speed.
Since most cars are geared for highway speeds you may never get locked up at reasonable highway mph.
Slippage = heat.

I run a 2400 rpm stall behind a 462" built for torque Buick in a 2400# roadster.
With 3.70 gears and a 30" tall tire it locks up ok, but there's probably a small amount of slippage still going on.

A climb up a long grade or a winding mountain road and monitoring trans temps will tell you if you made a good choice or not.

Keep in mind too, that stall speed ratings are somewhat arbitrary.
The 2400 rpm stall converter in my car stalls at 2800 rpm under high torque loading.

The converter - a B&M hole shot - is 1" smaller in diameter than the stock Buick 455/T-400 converter.

At one time I ran a couple of different big cams - adv duration 292 degrees - with dual quads.
Idle with a pair of Carter 500's was 600 rpm and the 2400 rpm converter worked fine.
Even so, a quality stock stall speed converter would have been a better choice.

Creep is much bandied about when using a stock converter in an engine with a bit of cam, but if you get the carburetion and timing well sorted out and a reasonable idle speed set, a stock stall speed would be no problem.
The 2400 rpm converter creeps at the lights, but a light application of the brake pedal keeps it under control.
A stock converter wouldn't be any worse under those conditions.