torque converters

[89camaroperson]

Can someone give a good explaination for what they do exactly and what the specification of say a 2600 stall converter means. Im going to get a rebuilt 700r4 and put a shift kit and the corvette servo in but i need to pick a stall. From what i have gathered it is best that you match the stall to your cam. i have a stock 305 and the cam sucks and i have no idea of the specs. What would be a good converter to have that would work well with my 305 and still allow a little for future improvments with the cam and overall power. I have read that a 1800 stall which is a stock s-10 converter works well. But i dont really know that. Thanks

[ct91rs]

A torque converter acts like a clutch does in a manual transmission. It transfers the engine power to the transmission. An 1800 stall would mean that the torque converter starts transferring power (i.e. putting a load on the engine) at approx. 1800 rpm. It would be similar to think of having a manual transmission, and revving the engine to 1800rpm, then letting out the clutch.

[FireFox05]

So anywhere below 1800 RPMS you have no power? Basically it's so that when you start out you are at the right place in your powerband, correct?

[wrightz28]

In a nutshell, the T/C is a fluid filled coupler to link the engine and transmission together insetad of physical contact like on a manual clutch system.

Stall speed works in relation to your camshafts power band (all depends on when your cam starts to wake things up if you will) in realtion to engine rpms.

For a stock application 1800 to 2K is just about right.

I'm sure seomone will chime in saying that's a pretty vague definition, but given your tone of question I think it's all you need to know for now.

[wrightz28]

Originally Posted by FireFox05

So anywhere below 1800 RPMS you have no power? Basically it's so that when you start out you are at the right place in your powerband, correct?

Not really, it's when the stator locks or unlocks to transfer direct power, otherwise there's allowed slipage.

[FireFox05]

So with a 3000 stall, under 3k you will:

a) not move at all
b) move just fine, but you won't get any real power untill 3000
c) none of the above and I need to do some reading

[wrightz28]

Originally Posted by FireFox05

So with a 3000 stall, under 3k you will:

a) not move at all
b) move just fine, but you won't get any real power untill 3000
c) none of the above and I need to do some reading

Pretty much B. The stator will freewheel until 3K then lock and apply full power to the spline shaft.

This is how a T/C goes bad, when the stator no longer functions correctly.

[FireFox05]

Ahh, okay. So what happens if you stick your foot in it from idle? It'll whine and complain untill you hit 3000 RPMs and then break your neck?

[wrightz28]

No, just won't transfer all the power to the driveline which brings up another point of the T/C, it is a Torque multiplier instead of using gears like in a man. trans.

So it would just feel like you're stuck in first gear so to speak

[89camaroperson]

thats what it sounds like.....that would be pretty cool though....minus the neck breaking part of course

[89camaroperson]

so would anything higher than 1800-2000 yeild any better results for me? I think the stock one on an rs is 700 is it not?....ewww let me slip in another question....tranny coolers....are they of much use in a street application? I know that when my motor is nice and cool and below that first bar( which seems to be the only time i can get any power out of the thing) I can sometimes bark the tire when going into second...not impressive i know but i think its cool.

[FireFox05]

Yeah that part would suck. But at least you would die your happiest, right? I mean what could be better than getting your neck broke by acceleration in your camaro? Good way to go, in my opinion.

[FireFox05]

so would anything higher than 1800-2000 yeild any better results for me? Depending on what you do with it, yes I think it should. Seems to me the higher into your powerband you can lock up, the better off you are. Well, within reason. I think the stock one on an rs is 700 is it not?....ewww let me slip in another question....tranny coolers....are they of much use in a street application? I have heard oth ways. Some say it wears your tranny more, some swear by it. I know over in the Grand Prix forum they shun them because those trannies have nearly never failed because of heat. I know that when my motor is nice and cool and below that first bar( which seems to be the only time i can get any power out of the thing) I can sometimes bark the tire when going into second...not impressive i know but i think its cool.

[89IROC&RS]

ok, let me clarify a few things on these. A stall converter is a fluid coupler. there is a housing with two propellers and a seperator called a stator. one propeller is connected to the engine, when the engine spins it forces fluid back through the stator and against the rear propeller, that turns the transmission. The converter does not lock up unless it is designed to. This is done through a manual style clutch on an electrical servo.

Stall speed is the maximum speed the engine can turn with the rear tires held still by the brakes.

flash point is the engine speed that it will zoom up to when you floor it.

[FireFox05]

Ahh, thank you so much. That made things quite clearer.