i have the cobalt ls auto with the 4t45e tranny

i kno that these transmissions are pretty awesome with torque ratings good to 325 ft-lbs WOOT!

the only problem i have is the stall speeds like 2000 rpm and i can barely spin my pos continentals with a launch

does anybody kno of any torque converter with a high stall speed that can fit on the 4t45e

thanx

bump

bump again come on guys i kno someone has done this

 

you could just up the power...
my stock tq converter doesnt even stall now. I can rev it to 2.8kRPM before i hit a rev limiter. I would imagine the stall speed is close after that though, near 3.1-3.4kRPMs

However, yes, there are high stall converters for our trannies. Take it to a tranny shop and they'll do it

 

stock stall will be nowhere near 3400rpm. the stall speed is tested in manual low, pump the brakes up and hold them, then put your foot right to the floor, the rpm will come up quickly to a point, thats the stall speed. if the rpm starts to climb after that you are overpowering the converter. a lot of things affect stall speed. with the same converter, the stall speed with a stock motor may be 2200rpm, but with your 265hp itll be much higher, likley around 2800 were you think your hitting a limiter.

when i have a high stall converter built from my supplier for a high performance application i have a huge form to fill out. included in that is displacment, cam specs, estimated horsepower and torque (or provide them with a dyno sheet), final drive ratio, tire size, ect. there are no "one size fits all" high stall converters, each application is different.

 

idk dude... I remember being stock and stalling around 2200rpms, but now at 2800rpms, it sounds like im hitting a fuel cut. it sounds exactly like im using a 2step. Vince thinks I may be putting the tranny into a safety limiter kind of function since the output shaft isnt moving, but the input shaft is moving way faster than what it should do stock (i think im getting the terms right). It also feels like the converter has a few hundred more rpms in it if the limiter wasnt there.

 

my trans builder asked me about what stall I wanted and Im thinking just barely over stock but i dont rememeber waht stock is for me. I want to not have any more traction issues at the track so i didnt wanna build alot of boost at the line. What stall should i get for a daily driver?

 

first off, when the tranny is in gear and your not moving, the input shaft doesnt turn. the clutches are applied, all that wont transfer motion is the torque converter. you wont hit any limiter when your in gear aside from the rev limiter, if it sounds like your hitting fuel cut you have something wrong. as i said, the more power you put to a converter, the higher the stall will be. i put a converter built for a 2.0l ohv with th125 into my friends supercharged 99 z24 4t40e (most gm fwd converters can be interchanged), and it stalled at 2800rpm, however that converter is rated to stall between 1800-2000rpm when mated with a 90hp 2.0l. this is a cheap way to get a higher stall.

celicacobalt: i myself would stick with a stock stall. a turbo needs a load on it to build boost, if you go with a higher stall converter you will be higher in the rpm ranger (and thus the torque curve)to get the turbo to spool, and when you leave the line itll be making way more power and spin. if you can harness that power then raising the stall speed is a good thing. also daily driving a high stall can be a pain, back to my friends z24, it would roll when you let off the brakes, but cruising around town the motor is buzzing a lot higher (the lowest itll get when not in lockup is at the stallspeed, at least when trying to maintain speed). if you end up with too high a stall you will have to bring the rpm way up to get the car to move. because of these issues we ended up taking the higher stall converter back out, it made the car much more enjoyable to drive on the street, and because of the low end produced by the blower a higher stall wasnt needed.

 

cool thanks, thats kinda what i was thinking, didnt want the car to be a pain to drive.

 

yea i just may go with a better torque converter from a tranny shop.

i mean i dont really wanna go too big with the engine maybe 2.4 mani, intake, exhaust and tune because im probably not going to have that car for too long.

but, i just hate being at a red light ready to race someone and ill brake torque to only like 1800 rpm and get left at the beginning.

 

I was thinking i dont want the problem of a "high" stall but it might be beneficial to have a slightly higher stall than stock.