[MightyMouse61]

What are everyone's opinions on stall converters? I would like to hear
about real world gains in performance from a high end converter. I currently have a B&M 3000 holeshot and have heard that I could be losing some power in it. Would a Coan or other be good to use on the street?
The car is a 70 malibu with a 383ci, 308/318 dur cam, TH400 with transgo 400-3 kit, 4.11 gears. Mostly for strip, but driven on street occasionally.

 

[elcaminodragster]

Ive heard B&Ms arent all that good for good drag times. I recently bought a coan 3000 10" converter but have yet to install and drive.

I did a big search and talked to many on here and found that the high end high dallor converters are the way to go. You can go cheapo with other things but the converter is the one you flat out do not want to go cheap. the cheaper they are the more the slip and the worse the times are.

I even read that some high end converters you dont really notice the high stall as much as you would with a boss hog lol.

Brands like ATI and Coan are considered the best. Do a quick search and you will find they are the most talked about.

 

[BillyGman]

What are everyone's opinions on stall converters? I would like to hear
about real world gains in performance from a high end converter. I currently have a B&M 3000 holeshot and have heard that I could be losing some power in it. Would a Coan or other be good to use on the street?
The car is a 70 malibu with a 383ci, 308/318 dur cam, TH400 with transgo 400-3 kit, 4.11 gears. Mostly for strip, but driven on street occasionally.

Are those camshaft duration specs you've listed the duration @.050 or are they the "advertised duration" figures? My guess is that they're the advertised duration. If so, then that doesn't mean a whole lot, and you really should list the [email protected] specs.

But if those specs you've listed are the [email protected] then you're going to need a much higher stall speed RPM than 3,500, and even if that is the advertised duration figures, I think that you'll still need a higher RPM stall speed than what you're talking about. That might be a different story if you had a monster displacement big block with an over-abundance of low-end torque, but not so with a 383 CID engine. But knowing the [email protected] would shed light on this topic. :yes:

BTW, I agree with the ATI suggestion. Some of the most "efficient" (which is what you want in order to have a minimal slipage percentage ABOVE the stall speed RPM during full throttle operation) torque converters are said to be the 10" ones for outlaw cars, but they're for real big cubic inch engines making gobs of torque all over the place, which isn't what you have there. You probably should give ATI a call and tell them exactly what it is that you want to do with this car and what your golas with it are. They will require you to fill out a vehicle spec sheet, or they will fill one out for you simply by asking you over the phone about each and every one of your vehicle specs (just as most any reputable torque converter manufacture will do...... unlike B&M :noway: ). According to what I've been told my torque converter manufactures, you want to shoot for a 3-5% slippage, (regardless of the stall speed RPM chosen) which will require a very "efficient" converter (and it won't be cheap so break out the wallet).

 

[MightyMouse61]

The dur. @ .050 is 234/244 with .488/.510 lift.
How would higher than 3,500 stall work on the street? I don't drive on the street for long distances, but if I did go for a long cruise in it, wouldn't it heat up the trans a lot more? With the car, I'm basically aiming for strip duty but still reliable on the street. I have had this car a daily driver once before when my truck was in the shop, would like to retain some of that ability.

Anyone ever have a cheap converter like mine and do a swap? I want to see how much difference. Don't get me wrong, I'm sold on the higher end converter so I will upgrade.

There are plans after my deployment to go with either a 177 blower or big inch small block(427/434/454). The new converter would come at the same time. So torque would be higher.

 

[BillyGman]

The dur. @ .050 is 234/244 with .488/.510 lift.
How would higher than 3,500 stall work on the street? I don't drive on the street for long distances, but if I did go for a long cruise in it, wouldn't it heat up the trans a lot more? With the car, I'm basically aiming for strip duty but still reliable on the street. I have had this car a daily driver once before when my truck was in the shop, would like to retain some of that ability.

Anyone ever have a cheap converter like mine and do a swap? I want to see how much difference. Don't get me wrong, I'm sold on the higher end converter so I will upgrade.

There are plans after my deployment to go with either a 177 blower or big inch small block(427/434/454). The new converter would come at the same time. So torque would be higher.

OK, that's actualy a much milder [email protected] spec than I had suspected, and a 3,000 stall speed RPM would be fine with that cam. But just to answer your questions, efficient torque converters (which will often cost more $$) will usually create less heat than a cheap one will which haves a high slippage percentage, and that often holds true regardless of what the chosen stall speed RPM is.

Don't get me wrong though. Having a higher stall speed RPM will increase the potential for heat, but the higher stal speed is not the only factor of influence there. If for instance you have a torque converter that is very inefficient and displays 12 or 13% of slippage at wide open throttle obove 3,000 RPM with the stall speed RPM being at 3,000 RPM, then that will be an additional cause of heat build up since your converter is in effect always slipping to a significant degree at all RPM right up to the engine redline. having a decent transmission fluid cooler helps a lot, but some very efficient torque converters won't even need a cooler using a 3,000 RPM stall speed RPM.

I had a car that I drag raced in which I replaced the stock torque converter when the car had only 4,000 MILES on it's odometer with an $800 aftermarket converter from Precision Industries. it was a 9.5" diameter piece, and the manufacture garanteed that this converter would reduce my ET's by atleast .5 seconds.

Wel, my ET reduction exceeded their claims because my car then ran .7 seconds faster than it had before with the factory stock torque converter on. However I must admit that the stock converter reporteldy had a 2,300 RPM stall speed, and i told the converter manufacture that i wanted a 3,000 RPM stall speed, so I'm sure that the highher stal speed RPM of the new converter also contributed to the lower ET's.

 

[Bud Crayne]

www.ckperformance.com

Call Chris for a converter built to your precise combo by a true "master".

You'll get 3 times more converter for your tight GI-bucks what others offer @ many more $$$$.

 

[MightyMouse61]

Ahh, everyday I'm on this site, I feel less like a dumb#$$ when I look at automatic transmissions and how they work...
Cool, thanks for the info guys!

 

[trroscoe]

I replaced a B&M 2400 stall converter with a 3000 stall from Coan and love it. I only have a couple hundred miles on the car since the swap but its like a night and day difference. The new 475+ hp 383 stroker might be part of that too though :yes:. The customer service I received from them was outstanding. They helped me pick the best converter for my combination and I am more than happy with it. I will be purchasing another converter from them for my Nova when the motor is ready.