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Old 02-08-2007, 02:25 PM   #1
bryanw1968
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Torque Convertor question.....

So, I have what I thought to be a 2000RPM stall. When I foot brake it it breaks the tires loose at 2100RPM. One of my buddies is trying to tell me that 1800-2000 is stock which I find hard to believe. I've always heard that even with a torquey motor you're still going to stall at less than the advertised stall speed of the convertor. My local speed shop is telling me that my current convertor is probably closer to 2500-2800RPM.

Any comments?

Thanks!
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Old 02-08-2007, 04:23 PM   #2
cooters
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Re: Torque Convertor question.....

stall is based on who makes the converter. Stock converter is about 1500rpm, the high the torgue, the higher the converter will stall. What you have could be sold as anything from 1800-2400 stall depending on manufacurer. There is no chance yours is above a 2400 stall

Last edited by cooters; 02-08-2007 at 04:24 PM.
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Old 02-08-2007, 05:32 PM   #3
bryanw1968
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Re: Torque Convertor question.....

Quote:
Originally Posted by cooters View Post
stall is based on who makes the converter. Stock converter is about 1500rpm, the high the torgue, the higher the converter will stall. What you have could be sold as anything from 1800-2400 stall depending on manufacurer. There is no chance yours is above a 2400 stall
So mine is in no way stock correct??
Thanks!
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Old 02-08-2007, 06:42 PM   #4
Myself
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Re: Torque Convertor question.....

I don't think so, I haven't seen a stock one yet that would hold to above 1500.
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Old 02-09-2007, 08:32 PM   #5
mnunn454
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Re: Torque Convertor question.....

Have read an article a few months back about stall speeds. The converter makers use 2 different terms. The term "Stall" (as I recall from the article) is the point at which the engine begins to turn almost 1:1 with the transmission (i.e. virtually no slip). For the condition we usually call stall, and that you described in your post, the experts call "flash", and it's the RPM point at which the engine is producing enough torque to overcome the brakes and the driveshaft starts to spin.

If your brakes were 4 times bigger than they are and you didn't break anything, then flash and stall would happen at the same RPMs. But typically they dont.

What you've got is a converter that with your setup "flashes" at 2100 RPM, and likely "stalls" 200-300 RPMs above that.

If you can do so without it kicking down a gear, try going real slow in high gear (engine revving in the 1500 to 2000 range) flooring it while a buddy wathches the tach. While you keep your eyes on the road, he should see the RPMs jump up to the true "stall" speed quickly, and hang there for a moment until the car speeds up, at which point the RPMs will rise more steadily from there up.

The more torque your engine produces for a given converter, the higher that true "stall" speed will be.

Hope it helps.
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