Deciding on a first stall

[SLP IROC-Z]

Originally Posted by Batman

Well until the stall locks it is similar to a slipping clutch. Flat may not be the word for it but the car will not drive the same way it does now. Higher the stall speed further into the RPM range it will act like that. Using a 4000+ stall on a stock cam that starts making power at a much lower RPM never made sense to me on a street car. If it was a car that was more track oriented then hell yeah crank up the stall speed to knock down the ET. Have decide which is more important to you, the extra .2-.4 at the track or manners on the street. It will all boil down to personal taste and what you as the driver can tolerate. I for one would not go more then 3600 unless you have plans for at least a cam upgrade. I think 3200 is the sweet spot for a stock engine, nice bump in performance without slogging along at low RPM

stall speed is half the equation, torque multiplication is the other half. you can take two converters both a 3600 stall, one with a 3.0 STR and the other with a 2.0 STR.

the drivability is going to be much better with the 3.0 due to the higher torque multiplication however its going to be less efficient at getting the power to the ground at higher rpms compared to the 2.0


and fwiw there isnt a converter yank advertises thats going to stall above 4000rpm behind a stock head/cam ls.

the PT converters advertised as head/cam converters, they will stall 400rpm lower behind a stock head/cam motor.
PT4000 = 3600
PT4400 = 4000

the PTs have a lower STR but are more efficient on the top end.

its important to match your gears/tiresize and converter together. i think alot of the reason people bitch about big converters is because they put 3600+ converters in cars with 2.73s, 3.23s and 3.42s, more load = more work.
if your going to run those gears go with an SS converter, youll need the extra torque multiplication your loosing with the stock gears.