Questions about torque converters

[1DangerousV6]

how do torque converters help your launch in an automatic?..what exactly do they do?..also..about how much is it to install one?

[Tru2Chevy]

A higher stall torque converter will allow you to launch from a higher rpm, which will get your car into it's powerband sooner. This will, of course, result in faster ET's.

- Justin

[1DangerousV6]

ok..the problem is...right now i can sit there on the street and put the brake and gas to the floor and my tires will just spin and smoke up at whatever the stock rpm is...on the STOCK converter...so i can only really launch from 1500 - 1700rpms...so would an aftermarket converter just make me spin even more?..is it kinda useless for me then?

[98Camaro3.8]

I don't really know a whole lot about autos and torque converters, but here is how I believe it works:

The torque converter will only spin up to a certain RPM before it can't go any faster and will cause the tires to spin. A higher stall converter will turn a faster RPM before the tires spin. So instead of launching at 1500, you could launch around 3000.

[1DangerousV6]

ahhhhh...i see...cuz im lookin at the people in the top 5 and they've got ones that go up to like 3000rpms and im wondering...how the hell do they sit there with their engine at 3000rpms without their tires spinning if mine are spinning at not even 2000rpms!?...this mod may be worth it for me then..because injecting the nitrous and handling the rest of the run i can do great..but i suffer up to like 3 tenths if i dont nail the launch...which is my biggest problem area..thanks guys! [img]smile.gif[/img]

[RallyRed 98]

let me put some more info in...

when your flywheel and converter are completely touching, they are said to be at "stall." around here they're called "stall converters" and when you describe a converter's specs, you say that it's a such-and-such converter. if the converter was at full stall at 3000 RPM, you would have a 3000 stall.

at any rpm before that, the output shaft from your motor is spinning faster than the input shaft to your transmission because they are not at lock up.

that's what multiplies your torque and allows you to launch harder and faster.

it also destroys your transmission faster.

['98 BlackBird]

This should be moved to the drivetrain section. Do a search for Torque Converters and low and behold you will find all the answers. [img]tongue.gif[/img]

[98Camaro3.8]

Originally posted by '98 BlackBird:
low and behold

FWIW (not much, I know), it's "Lo and behold". [img]tongue.gif[/img]

[Camarorulz]

I have an Edge 3000 stall with a 2.4x STR. Its worked out great for me and these are the observations I've made about it over a year and a half and 30,000 miles.

The torque multiplication factor makes a difference. If you get a converter with a higher multiplication factor (called STR) more of your torque will go to the wheels quicker. Higher stall converters also have a "looser" feeling when driving: your rpm will stay up higher, longer, sometimes resulting in somewhat decreased gas mileage. A converter can also result in decreased gas mileage by the "lead foot" factor, hehe. :cool:

A higher stall converter will allow your engine to spin up faster. This is the best way I can describe it while having little technical knowledge of how the converter works. Your rpm will shoot up faster from idle, resulting in harder launches.

Some people say the advantage of a high stall converter is that you can launch at a higher rpm. This is true with some converters, but with others its better to "flash" them (mash the gas) from idle to get a better launch.

[StudlyCamaro]

lets also not forget that the higher the STR the more likely that your trap speeds will suffer

[Jerriko]

Originally posted by RallyRed 98:

when your flywheel and converter are completely touching, they are said to be at "stall." around here they're called "stall converters" and when you describe a converter's specs, you say that it's a such-and-such converter. if the converter was at full stall at 3000 RPM, you would have a 3000 stall.

I'm not sure I understand that statement. Flywheels are used with clutches, flexplates are used with automatics. Second, the flexplate is bolted to the converter so they are always touching. The converter is split into two halves. The impellor is the half that is physically connect to the crankshaft and the turbine is the half physically connected to the trans. The impellor directs fluid pressure against the turbine by the use fo fins attacted to the impellor and turbine. The size (and distance between the fins) is what determines the TC's stall.

Stall is the speed (rpm) which the impellor forces enough fluid against the turbine to turn it. Stock converters around 1800 rpm meaning if you hold the brakes down, the tires would start to spin around 1800 rpm. With stall convertors, say a 3000 stall, the rear tires would not start to spin until you reached 3000 rpm, while braking. As was said earlier, a stall convertor would put you into your power much sooner.

[ December 18, 2004, 06:47 AM: Message edited by: Jerriko ]

[1DangerousV6]

i guess thats where slicks home in handy..cuz even if my tires werent spinning at 3000rpms..if i tried to launch from that high i would just sit there spinning on the line [img]graemlins/burnout.gif[/img]

[AlienInv8r]

yes. you'd definitely wanna get some slicks with an high stall converter. It wont affect your daily driving though much either, they drive fairly normal if you apply gas at a normal rate. The stall speeds and all dont come into play unless you brake stall or flash the converter.

I definitely would like to get a nice one at some point...

[1DangerousV6]

yeah im definitely interested in one too..i'll have to see how the car runs next season...thanks guys!

[FireFighter]

Just be carefull with a high stall and sticks thats how I blew the trans in mine and thats the reason I got rid of the camaro.