wendscot

I am having my 700r4 Tranny rebuilt. I am getting all the goodies done to it, including a 2500-3000 stall converter. What exactly does the stall do? I found the motor I want to put in it and it required at least a 2500 stall so that is why I wnet ahead and got it during the rebuild stage. I always thought it just kept the car from lunging forward when sitting still...cause of cam lope. I am being told it does much more than that...so I was wondering if anyone else knows what it does.

Thanks,
Scott

jimmy_mac

It allows you to stay in your engines operating range better. Most motors built for performance are dogs at around 1500 rpm. So the torque converter doesn't completely engage the tranny till a higher rpm. That along with a good first gear gets you to the motors power band quickly.

Beware of numericall low geared rear ends and high stalls though if you do a lot of street and highway driving. Having a car with 2.73 rear gears and an overdrive and 2500 rpm stall is not good for 65 mph driving. It will heat up your tranny quick cause your motor never makes it up to 2500 rpm.

You really need to have a trans cooler and temp gauge for the tranny if running a higher stall converter if you want the tranny to last. Don't let those temps go much over 200 if at all possible.

wendscot

Thank you sir. I was told for a stock TPI 2500 was good to go, but as I said before I will be putting a crate motor in it next year...that requires 2500 ne ways.

As for cooling the tranny, it is getting trans cooler put on it (mounted in front of condenser). I will get a gauge, been wanting a pod with Fuel pressure gauge ne ways.....so I can get a dual pod and put tranny temp and FP at once......lol.

I was reading where it said you can have to high of a converter, so I hope on my stock motor a 2500 will not be so bad for now. I have a 3.23 rear gear and on the highway I usually cruise 75-80 (2900 rpm's) so that should be good right? I do mostly in town driving though.

jimmy_mac

2500 really isn't that high. But it is noticeble and IMO it's a good stall for a TPI or a slightly modified motor. And the 3.23s are also a good compromise gear for street/strip with that stall. You should be fine driving around town with that. And if you do install the temp guage you will learn what type of driving heats it up anyway. You should be good to go.

wendscot

Thanks for the help

Still need one more question answered. Will the stall allow me to be quicker off the line? Will it help with tire spin? As my car was I would spin all the way through first gear and bark second, if I didn't feather the throttle. Matter of fact just to let you know a little about the L98 in it (stock, but SLP equipped from the factory) I was beating my friend (he has T-56 LT1 95 Formula) till my tranny started acting up. It wouldnt shift right and he cought me, but still I stayed about a half car length from his bumper even after he passed me. Had my tranny been shifting correct I think I could have beat him by a bumper. As I have said before I do not know anything about stalls....I read up on it, but it was telling me what a converter does all together....not necissarily how a stall wil imrpove performance.

Fevre

Higher stall t/c will make traction worse since it allows the eng to rev higher into the torq band before engaging

jimmy_mac

From a dead stop you are gonna probably have traction issues no matter what stall you have with the TPI motor and street tires. That's just part of getting an optimal launch. My experience has been it's easier to control the tires with a loose stall compared to stock. But that's just me.