torque converter pro stall?

[marshmallow15]

before upgrading my torque converter, i want to know what does 'pro stall rpm speed' mean? there's a beefed up auto supra here with a 3300 stall torque converter on the car. i also noticed levelten wants you to choose a pro stall rpm speed for their unit.

[guyaverage]

Stall speed, in general, is the maximum rpm your engine will hit when it is in drive, the wheels are locked, and the gas pedal on the floor. To get an idea of what yours is, put your tranny in drive, set your parking brake, and plant one heavy foot on your brake pedal, and hit the gas. (tell your moron friend to not stand in front of the car while this is going on.....) Whatever rpm your engine shoots up to is your 'stall speed'. Stall speed is a function of your engine AND your torque converter together. If your engine is bone stock and the stall speed is, say 2200 rpm, if you go out and put on a different intake, headers, free flow cat, advanced timing, and every other piece of junk to get a few extra ponies, your stall speed will increase some because your engine is making more torque and will overcome that much more resistance. Stall speed really needs to be matched to your engine to get the most out of it. If your engine makes maximum torque at 4500 rpm, then you dont want a stall speed of 1300, you'll be way below your torque peak and your launch will be slow. On the other hand if its too high once you get going you'll be wasting lots of power. I had a 5.0 Mustang that had a high stall speed setup on it and it would launch off the line like a raped ape, but once it got going or were just driving around town, it felt like mush.

[marshmallow15]

ahh ic.. so for example, if i feel some good torque up to 4000rpms and it just feels laggy after that, a good stall speed converter for me would be 4000rpms?

[guyaverage]

No actually you want your stall speed to be below your torque peak, by several hundred RPM. If you're just 200-300 rpm off ideal, you'll be cutting your 0-60 times and you could end up with the mush-box like what I had a few years back. If you are really serious about spending a lot of money on a new tranny and torque converter, whoever is taking your money needs to be able to answer specific questions about which one is best for your car, instead of making you just pick one (thats just my 2 cent opinion). If you have a bunch of mods to your engine or you are planning to do a lot more, you might want to wait until everything is done, or spend a few bucks getting your car dyno'd to see what your torque peak is so you can get the best converter. My advice here is, go to the google god and look up "torque converter" and "automatic transmission" and "high performance automatics" and terms like that, go to as many high performance aftermarket tranny sites you can, read up on everything so that it all makes sense and that you understand it so that when it comes time to plunk down your $4000 you dont get royally screwed. Being uninformed like I was is your worst enemy. I spent a bunch of money building a tractor engine (Tons of low rpm torque, but certain death above 4000 rpm) and had it bolted to an automatic that had a rediculously high stall speed. It didnt take people long to realize I would seriously smoke them off the line, but once we got up to 40-50 they would blow right past. I had spent about $3000 just to end up getting beat by a freakin Nissan. Embarrassed and broke all at the same time.

[marshmallow15]

hey tnx a lot for the help.