torque converter question

[Mark Kovalsky]

I can hold my truck at 2800rpm at 30psi of boost and then launch....

Then your stall speed is at least 2800 RPM. If you have the go pedal all the way down then that is the stall speed.

Stall speed isn't fixed in the torque converter. If you increase engine power and don't change the torque converter it will stall at a higher RPM.

 

[Dieselboy.]

Just checked my PCS log, 45-70% slowly building up to 2200ish RPM, then I ramp in to around 85% TPS all the way up to 2800ish and floor it. Last RPM at 0 MPH is 2899 at 94% TPS. Wouldnt say it was above 2200 for more then a few seconds.

On a built trans though, I dont see them throwing in a 2800 stall converter unless I asked for it ?

Unless Im mis-interpreting you Mark

 

[Mark Kovalsky]

You're not misinterpreting me. That converter is stalling at 2899 RPM.

Stall speed changes with engine power. A converter that stalls at 2000 RPM will stall much higher if the engine power is greatly increased.

 

[Dieselboy.]

Ok, I getcha.. You mentioned the 1600 converter drove better in your opinion. Care to elaborate more on this compared to a "high stall"

What does it actually change ? I hear guys complain DD habits on the higher stalls, but cant you just adjust lockup in tuning ?

 

[Mark Kovalsky]

It doesn't have to do with lockup. A lower stall converter will rev at a lower RPM when the converter is unlocked.

 

[ToMang07]

Thanks for explaining that, Mark. :bowfast: