stall speed help

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mopardemon340

mopardemon340

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need a stall speed for a 904 trans.. 72 demon with a 408 stroker, 529 torque and 472 hp, run on street/strip. 3.73 rear gear for now but going to 3.23 soon.. 265/60/15 tires
 
The torque converter Vendor/Manufacturer can answer that best; he'll want to know your cam specs in addition to the info you've posted. Just went through that myself.
 
Depends on your goals. How much street and how much strip? The most efficient/fastest stall for the track would be matching the stall speed to peak torque of the engine.

However, with those 3:23's even a very high quality converter that is nice and efficient will have moderate slippage cruising around town at 35-40mph with a converter that's made to stall at 3800rpm.

If it's more street than strip, but you still want a good launch I'd aim for 2800-3200 stall depending on torque. A nice converter will still have really good manors on the street if youre cruising closer to its "stall speed"
Joe
 
Call the torque converter manufacture's. PTC. Pro Torque. Lenny over at ultimate. Etc etc.

I bought a new converter last summer. Just got ahold of everyone. Told em my specs and what I was looking for. Ended up going with a PTC unit. I know a few guys who race with them and they have had excellent success with them. I got a custom built unit. 3000 stall. 9.5 inch. Billet front. Etc etc. For LESS than an off the shelf B&M unit. And if I make any changes and need to up my stall. I can send it to them and they do one adjustment on the cheap (can't remember exactly what).

Like I said. It's custom built to my exactly car specs. For LESS than off the shelf. You really can't go wrong with that. One area you should never skimp is the converter.
 
That will depend a lot on how you are gonna be driving it, and how much traction you have, and on your chassis set-up.
But with 529 tq/472hp,
and 3.23s,
Ima guessing you will want to be Mr.Mellow,lol. If that is true, Too much stall will just blow off the tires, so easy does it........
With the skinny rollers back there,a stock 340 type stall will do it. I think they were around 2250
With 275/60-15 stickeys ,an LSD, and Caltracks, you will be able to harness some of that torque, and perhaps that will allow more stall, say 2600. Or perhaps 2800.
But I tell you what, with the preponderance( I love that word) of low-rpm grunt with 529/472, you are gonna have to baby it out in first anyway so just about any old stall will do on the street. You have Sherman-Tank Power, stuffed into a Jeep. On the street, you're kindof screwed. I highly recommend a 1 barrel,lol. Ok how about a spreadbore; at the very least a small vacuum secondary carb.. 3.23s will take you to 60mph@ 6200ish with 28" tires. There are no street tires that can handle your engine at WOT unless you do some serious suspension work.
At peak torque, perhaps 4500rpm(45mph), you will be putting 4186ft lbs into the rear axles. Some of us 360 wranglers will need 4.30s to do that, and we will hit 60 at about 8000 rpm, so we are gonna have to shift a lil sooner,perhaps around 48/50mph. But our little 360s with 4.30s can blow 295s away with 2800TCs .
So, long story short
What have you done to your suspension/tires to try and live with these 529 ftlbs?
 
AJ/FormS said:
That will depend a lot on how you are gonna be driving it, and how much traction you have, and on your chassis set-up.
But with 529 tq/472hp,
and 3.23s,
Ima guessing you will want to be Mr.Mellow,lol. If that is true, Too much stall will just blow off the tires, so easy does it........
With the skinny rollers back there,a stock 340 type stall will do it. I think they were around 2250
With 275/60-15 stickeys ,an LSD, and Caltracks, you will be able to harness some of that torque, and perhaps that will allow more stall, say 2600. Or perhaps 2800.
But I tell you what, with the preponderance( I love that word) of low-rpm grunt with 529/472, you are gonna have to baby it out in first anyway so just about any old stall will do on the street. You have Sherman-Tank Power, stuffed into a Jeep. On the street, you're kindof screwed. I highly recommend a 1 barrel,lol. Ok how about a spreadbore; at the very least a small vacuum secondary carb.. 3.23s will take you to 60mph@ 6200ish with 28" tires. There are no street tires that can handle your engine at WOT unless you do some serious suspension work.
At peak torque, perhaps 4500rpm(45mph), you will be putting 4186ft lbs into the rear axles. Some of us 360 wranglers will need 4.30s to do that, and we will hit 60 at about 8000 rpm, so we are gonna have to shift a lil sooner,perhaps around 48/50mph. But our little 360s with 4.30s can blow 295s away with 2800TCs .
So, long story short
What have you done to your suspension/tires to try and live with these 529 ftlbs?
Click to expand...


Yeah, traction and tires is another layer of the what's your goal question... That thing is gonna destroy tires!
 
Contact Paul at turbo action. Go with a 10" converter not a 11".I have a 500 hp 570 ft lbs of torque with 323 gears and the same size tires.I have put 2500 street miles on it with no problems it stalls around 3200.Paul is a really good person to deal.
 
mopardemon340 said:
need a stall speed for a 904 trans.. 72 demon with a 408 stroker, 529 torque and 472 hp, run on street/strip. 3.73 rear gear for now but going to 3.23 soon.. 265/60/15 tires
Click to expand...

As the others have said, Go to a professional for the best match. Those 904's are light and transfer lots of power without much parasitic loss. I run a 408 with slightly more output, and a lower 3.91 rear gear set with a 2.76 to 1 first gear ratio. It also has a .67 overdrive for practical daily driver use. The only way its really predictably safe to drive on the streets is because of todays tire technology. I highly recommend the Nitto Drag Radials. They work incredibly well in wet and dry conditions, last me for several years and are reasonably priced. They also have a 186mph speed rating.

B1.jpg
 
mopardemon340 said:
need a stall speed for a 904 trans.. 72 demon with a 408 stroker, 529 torque and 472 hp, run on street/strip. 3.73 rear gear for now but going to 3.23 soon.. 265/60/15 tires
Click to expand...

i'd call all three of the popular ones.. dynamic,ptc and ultimate and see what they recommend..

the biggest thing when talking with them is to be 100% honest on intended use.. and also have as much information as possible about your combo.. if not 100% honest about the intended use or the combo you will not be happy with the converter..
 
thanks guys ill give these places a call for what we want.. im still working on my suspension and will be going with caltrac and stiffening up the frame as well.
 
abodyjoe said:
i'd call all three of the popular ones.. dynamic,ptc and ultimate and see what they recommend..

the biggest thing when talking with them is to be 100% honest on intended use.. and also have as much information as possible about your combo.. if not 100% honest about the intended use or the combo you will not be happy with the converter..
Click to expand...
As abodyjoe and others have mentioned, you must be 100% honest with any converter supplier, or sure as he.. you'll get the wrong one. You mention that your engine makes 472HP and 529ftlbs of torque. From this, I guess it's safe to assume the engine has been on a dyno, and if so, you'll have the dyno sheet. If that's some PC DYNO readout, it's not worth the paper it's written on. Make sure that your converter supplier gets a copy of it. Don't let price be your final guide as to where you buy your converter. Get the RIGHT converter for YOUR application and deal with a company that has a good reputation and a warranty policy. Also ask about re-stalling the converter if and when you change the rear axle ratio. When you change the axle ratio, the stall will be affected. Some companies will charge to re-stall a converter, some won't if done within a specific length of time. The company I worked for in the past had a 1 year/1 time only, re-stall policy at no charge to the original owner.
 
transman said:
As abodyjoe and others have mentioned, you must be 100% honest with any converter supplier, or sure as he.. you'll get the wrong one. You mention that your engine makes 472HP and 529ftlbs of torque. From this, I guess it's safe to assume the engine has been on a dyno, and if so, you'll have the dyno sheet. If that's some PC DYNO readout, it's not worth the paper it's written on. Make sure that your converter supplier gets a copy of it. Don't let price be your final guide as to where you buy your converter. Get the RIGHT converter for YOUR application and deal with a company that has a good reputation and a warranty policy. Also ask about re-stalling the converter if and when you change the rear axle ratio. When you change the axle ratio, the stall will be affected. Some companies will charge to re-stall a converter, some won't if done within a specific length of time. The company I worked for in the past had a 1 year/1 time only, re-stall policy at no charge to the original owner.
Click to expand...
did the dyno yesterday after noon..
 
Where does it make peak torque? For max performance you want the stall 500rpm above that number. Obviously that may not translate into the perfect street convertor for your application. My last car made peak torque at 4000. That's right where they set my flash stall up. My current car makes peak toque at 3500. My current convertor flashes right to 3500. They are both primarily street cars.

They will want that dyno sheet. This is great info to have because even if you tell them all of the info but don't have dyno numbers there is still some guessing.
 
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