Thread: Stall Torque Converter ???

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i just did a moter swap on my 92 firebird i used the stock Torque Converter and 700R4...i put a nice big cam it sounds good but the power isnt there from 0-about 1500 rpm...i have a Torque Converter that a guy gave me. he told me its a 3500 stall but i dont know if he know what he was tlking about....
if it is a stall i would love it use it.. but how would i tell?....i under stand a little how a stall works..... i guess i just nead a little help with this hole Torque Converter

if you can help me

thanks.....
Brady Zimmerman

all you can do is put it in and see how it runs... and thus see if the dude knows what's what.

As the saying goes: smell it first. If it smells burnt, you don' wanna use it.

Here is how this works. A higher stall speed torque converter allows the Rpm’s to increase when you launch from a start. The Stall speed is rated at a ‘flash’ speed. To get that flash speed for your car, just punch it from idle and watch the tachometer go up before the car starts to move. The reading you get will be the flash stall speed that your stock torque converter has now.

A higher stall speed torque converter allows more ‘slip’ so the Rpm’s increase before the torque converter locks up. If you make modifications to your car that include a longer duration camshaft (230 degrees @ .050 lift), you want a higher stall speed torque converter because your motor has lost bottom end torque and will be lazy off the line. That is, your motor does not have the low speed torque it had with the shorter duration camshaft (218 degrees @ .050 lift).

You can upgrade to a higher stall speed torque converter without changing your camshaft. This would increase your launch by letting the Rpm’s slip until say 2200Rpm’s.

Remember that a torque converter doubles the engine torque to the wheels. That’s why an automatic transmission vehicle will jump off the line faster than a manual transmission vehicle if they both launch at the same Rpm. Also, higher stall speed torque converters develop more HEAT due to the increased slippage and will require additional cooling requirements.

ok...thanks

this is all makeing good sence...

now how would i find out what stall speed i would nead to use..?

You can call any manufacturer and get a recommendation, but a rule of thumb I use is to match the stall of the converter to the basic rpm range of the cam. If the cam manufacturer says his cam will make power from 2,500 to 6,000, then I'll use a 2,500 stall converter. If I'm in doubt, I'll call Jim Hughes.

If it is for a dialy driver, don't get wild. Saw a car once trying to negotiate stopngo traffic at a red light, and the road was wet. Every time he would try to inch forward, the ass end of the car would jump sideways. Not cool.

Originally posted by firebird77clone
If it is for a dialy driver, don't get wild. Saw a car once trying to negotiate stopngo traffic at a red light, and the road was wet. Every time he would try to inch forward, the ass end of the car would jump sideways. Not cool.

sounds like to me the nut behind the wheel was looser than the conv.