Torque Converter

[lt14mla]

hey i just had a question about torque converters. What exactly to they do, are they harmful to your car or can they cause problems. I've herd thats they are the best mods to auto firebirds. How come? Is this any difference between this and a stall converter? If so, how so? thanks

[Joe 1320]

A very watered down expaination:
A torque converter in an automatic trans functions like a fluid clutch. A manual has a mechanical clutch that disengages the engine from the rest of the driveline or the engine would stall when you came to a stop. An automatic is always engaged, but the fluid clutch (torque converter) allows a percentage of slip to prevent the engine from stalling when stopped. As engine rpms increase, the fluid being forced through the torque converter exerts more pressure on the internal fins and more power is applied to the rest of the driveline. There is a torque multiplication that occurs with an automatic that increases with rpm. Stall speed refers to the rpm that the converter reaches under full engine throttle while the rest of the driveline is locked. Stall speed is actually approximate because the amount of power the engine produces has an effect on what rpm the converter will stall to. The same converter behind a 300 hp small block may stall at 2800 rpm, but a 500 hp nitroused motor may push the same converter to 3100 rpm. Then there's the ability to retain a lock up clutch to elimiante slip at cruising speeds.......

Generally, stock LT1s and LS1s like from 2200 rpm (conservative street) to 2800 rpm (street strip).

[Hobbs95]

i've heard that the torque on the LS1s is produced at a higher rpm and the LT1s lower would a higher stall be required for a LS1 compared to a LT1
are all 4l60E torque converters compatible?
What should i look for if i were to buy a used one, i have a friend who has a 2000 w/ a vigilante and has prolly used it for 10k miles and he wants a higher stall he told i could have it but i don't want something i can't use

[Kevin - Blown 95 TA]

I think there's a dif between the LS1 & LT1 4l60E converters. Not sure what - if it's the difference between the flexplate or something else, but they are listed as different part numbers in the catalog.

[Hobbs95]

aftermarket too?