I read about people installing torque converter stalls to their corvettes, especially higher horsepower cars. What exactly does it do, and what do the numbers (i belive the RPM rating) mean for its performance??

If i start to significantly add torque or HP to my car, does it become a necessity?

 

All torque converters have a stall speed, stock ones around 1200 to 1500 rpm. High performance converters have higher stall speeds which allow for more engine torque and horsepower to be released kinda like a manual transmission with a clutch. You can launch at a higher rpm where your engine is in more of its power band. Also, higher horspower engines that have a lot of valve opening overlap have to have a higher idle speed and with a stock converter you will always be fighting the brake pedal. Stall speed is when the converter fins inside the converter actually start moving the output fans to release energy to the transmission. This is kinda a basic explination of how a stall converter works. [8D]

 

mech, is preaty much on,the money, a converter is used for high lift and deration cams,put it this way if you have a cam producing power from 3500 to 7000 that is your power band,so you want to launch at 3500 rpm that is when the motor starts to make its power, what you do is you push down on the foot break and step on the gas,the engine will rev to 3000rpm to about 3500 rpm ,then when u let off of break the car will launch, because u are taking off at 3500 rpm! now ther are cars with tranny breaks wich work when u push a button a solenoid will engage the valve body, and all you have to do is step on the gas pedal, the motor will rev to 3500 rpm the max stall the converter will prduce,...let go of the button and the car will rip your head off,,,,,,,,,,,,now if i have a motor with about 270'deration @,050" and put in a 1500 stall ,and when i put the car in drive it will put a huge load on the converter and the car will stall,shut down,now if i had a 3500 stall and put it in drive it will slip more thus the engine will keep running,you have to mach the converter with the cam and intake rpm range,

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Simply put the a high stall limit results in the engine being able to rev up higher, to produce more HP, when you floor it, particularly off the line. You see people match them to their cams: put in a high life long duration cam and the motor does not produce any power down at low RPM, so the stall converter allows it to rev up high even right off the line. A good drag car will have the stall coverter matched to the RPM where the cam just starts to kick in max torque. But a stall converter does not have to be put only on an engine with such a cam: iots independent of that, and on any car, it will still permit the engine to rev high while starting out, getting more power because you are reving more. It IS harder on the transmission, too (it runs hotter, etc.) but usually the ocnverters are designed for that (still a good idea to change fluid more often,e tc.)

It realy makes a difference. With a powerful engine and a high stall limt it will just about rip your head off when it comes off the line, jumping the first 60 feet a lot faster than stock. But if you drive on the street it will be a pain, the engine will always rev up when you move away from a light, etc. You push down on the ga and just want to ease away in traffic, and the damn engine revs to 4000 RPM anyway- you don't leave fast, just at the speed you want, but you make lots of noise and vibration. It gets old in a hurry.

There are premium stall converter kits that permit you to have a two stage selection of stall: 1200 or so for daily driving, then flip the switch, and 3000 or higher stall speed for the track, etc. Worth looking into.

 

lee ,i have never heard of that kind of converter befor i have bean through them all ,b&m,jw,huges,tci,dynamic,and many others,,the vanes inside the converter are bent on a angle, they are welded in place the only way to get more or less stall is to bend the vanes,the more angle the more stall,i have a neal chance converter in my mustang,6500 stall with tranny break, and i can addjust it,the converter comes apart, ,,,breaks in half,,,,,,,,and i just dont see how there could be any electronics is side, how would it be able to, the converter is spining 6000 rpm and there would be no way for a wire, for a swich,i am not saying your wrong, but i have bean drag racing and building aoutomatic trannys for years,and never heard of that kind of converter.the only other way would be through the pump,and i dont see that happening,who make this converter, i would like to read up on this converter,