Okay, I have been on this site for a couple of months, so I have to ask ....

I read all about people changing stall converter from say 2000 rpm to 3500 rpm etc, etc, etc. to get better 1/4 mile time and such.

I must admit I have no idea what any of this means. Can anyone explain to me what this stuff means and what it is doing?

Ed-u-cate me please, thanks in advance.

 

put one foot on the brake, and one on the gas: now push both at the same time. This will give you a decent idea of what stall is. Otherwise called "bringing it up against the converter" For a stocker it will be around 1200-1500 rpms. what an aftermarket converter does is flash to say 2800 rpms and put you into your powerband quicker. But be warned, if you run normal street tires they dont hook in 1st gear anymore on the street, but do "OK" at the track. Hope this helps. Prorac1

 

http://www.tciauto.com/tech_info/tor..._explained.htm

"Torque converters explained"

Should help you out a bit.

-Mindgame

 

For a 94 you shouldn't go over a 2800 stall. You might have shifting problems.

 

I am not a converter expert, but wanted to point out one thing. "Stall" is both a function of the converter design and the amount of torque applied. A converter that stalls at 2,500 with a 300hp small block would perform completely differently behind a blown big block (if it didn't just disintergrate!). More torque = higher stall speed. That's why high end converters are always custom ordered for a specific application. I spent ~1/2h on the phone with Coan when I ordered a converter earlier this month Lots of questions and discussion about the torque curve of the motor, weight of the car, gearing, intended use, etc. Hopefuly, it will perform as intended and stall at ~3,200rpm!

Rich Krause

 

Thanks, all. I don't think I am going to change anything on my car right now, but after everything I know and learned on this site this is one thing I didn't know about.

I will look at some info, but what does stall mean? The converter stalls after a certain rpm and doesn't operate, therefore you can't get a good jump off the line? Higher rpm stall puts you in a better torque/hp range so when you take the brake off you just take off like a banshee?

 

True Stall: The rpm the engine cannot exceed when the driveline is locked. The most accurate way to determine true stall is by locking First gear and Reverse with a transbrake and observing engine rpm at wide open throttle (WOT).

Flash Stall: The rpm the engine “flashes” to when launched from rest at WOT. A converter will often briefly flash to a higher rpm than its true stall speed.

Brake Stall: The rpm the engine cannot exceed with the brakes locked and the driveshaft not spinning. Brake stall isn’t usually an accurate measuring tool since the engine often overpowers the wheels before the true stall speed is reached.

If you have enough traction and don't care about streetability you want the converter to stall at peak torque. But a converter with a very high stall is less efficient than a lower stall (poorer mileage, lower trap speeds, etc.) and can be very annoying to drive on the street. So street/strip converters are a compromise. Ususally, they are selected to stall quite a bit below peak torque, but the car wouldn't have the traction to launch at peak torque anyway so not too much is lost. Race converters are very loose. With a high rpm motor, a stall in the 5-7,000rpm range isn't unheard of.

There's a lot more to converters than stall, as I am in the process of learning. Just as with other driveline components, strength costs $$$ and weight. The Coan converter I bought (10") weighs ~30lbs. Kinda suprised me, how heavy it is. Bigger (diameter) converters in general have lower stall speeds and are used for higher torque motors.

The definitions above are from http://www.carcraft.com/techarticles/80098/, which I found well written and informative.

Rich Krause

 

anything over 3000 might be pushing it without any problems as stated...3200 might be do-able but i'd go with a 2800 or a 3000 . Vig that is =)

 

I have a 3200 in a 94' with pcmforless tuinning. Have not taken to the track to see if It solved the no shift problem. But thier are severeal ways to fix it in 94's
Just to let you know.

 

What are the ways in a 94?

 

going to obdII or pcmforless.

 

I'm in a similar knowledge position as you since i have a 6 speed, so maybe this will help. The easiest way to understand stall is brake stall. Like they said, put your foot on the brake, and push the gas with your other foot. when your tires start to break loose, that's your brake stall speed. Stall does not mean that same thing as when an engine stalls (i.e.- doesn't work). It basically means that's how high you can rev your car until it starts spinning the tires or creeping forward. Since most engines don't even start to make power until about 2500 rpms, "stalling into your power band" means getting a stall that will let you launch at your engine's best range (torque and horsepower band.)
For all of you guys who know the aspects of stalls better than I do, I hope i explained it truthfully, but in layman's terms that even us six speed guys can understand. Later.