When do you want a Low Stall Torque Converter and when do you not?
What are the pros and cons of having one?

 

You want a low-stall converter if your engine gets up on the powerband relatively fast - like a CTD with lots of grunt down low.

High-stall to allow the engine speed to flash up into it's powerband before significant fluid coupling occurs - like a gasser.

Powerband matching aside, TCs are analogous to flywheels on a manual for launching purposes... heavier vehicle needs a heavier flywheel/higher stall converter, etc.

Also, TC lockup is important for better fuel economy and lower tranny wear.

 

Low stall converters work great on a stock truck or with a stock turbo. Run a big turbo.... you'll get killed off the line.

 

Even on a stock turbo, i can notice my DTT prevents spooling a touch vs stock trans...at least that's what i think it is....if i just mash the pedal from a stop, i get lot's of smoke and a 1 second pause....then off like a scalded dog....

 

mine is the same way, if i stomp it from a dead stop, it rolls out a cloud like crazy, then all he** breaks loose!!!