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I'm going to go ahead and copy and paste a bunch of info from other sites (who also copied and pasted it) regarding stall converters. There have been an increasing number of questions regarding them, so I think it would be beneficial for people. Mods can sticky it if they wish...
Do I really need a tranny cooler with this stall.
Yes. As a by product of the stalling effect, more heat is created. This heat is damaging to the tranny and the way to deal with this is to get another tranny cooler(all Fbodies came from the factory with a external tranny cooler)
Do I need a shift kit with a high stall?
Unlike the cooler, a shift kit is not mandatory but its a good idea. The shifts with a stall might feel a little long so when you add the shift kit, the shifts quicken just a little more than stock.
Do I need a stall with a cam???
Usually. Most people tune the car for the cam which involves raising the idle speed on the car. Without a stall, you will have to just stand on the brakes to keep the car still because the engine is now idleing at 800rpm. Also, a bigger cam shifts the power band of the car higher, a stall enables you to jump into the cam's powerband faster so youll be faster.
What exactly does a high stall do?
1) Higher RPM Launches. This is self explanitory, but so is the search button so ill explain. You can brake stall to a higher rpm and also flash stall to a higher rpm.
2) Static Torque Ratio. I will leave the explaination of this to the experts at Yank
"The stall torque ratio is the amount of engine torque that the torque converter can multiply at a particular rpm level. By definition, stall torque ratio is when the turbine is at 0 RPMs and the converter is at maximum designed stall. This will produce a positive push on the turbine to increase the torque to the input shaft of the transmission, multiplied by the designed stall torque ratio of the torque converter. For example, a stall torque ratio of 2.0 would multiply 200 lb. ft. of engine torque to 400 lb. ft. of torque at the transmission input-shaft. The misconception of stall torque ratio is that more must be better. This is not always the case. High stall torque ratio applications, typically are for industrial equipment or engines with limited low rpm engine torque. With high stall toque ratio converters, there are important trade-offs. What you take at one end you give up on the other. Typically, a torque converter with a very high stall torque ratio, such as 2.0-2.5, will be much less efficient above its rated stall speed. There is a sacrifice in higher rpm efficiency to achieve high stall torque ratios. That lower efficiency translates into less horsepower transmitted to the tires over an RPM range. The problem with a high stall torque ratio converter is that it is only high while the car is not moving. Maximum stall torque ratio occurs at wide open throttle with no rotation of the transmission input shaft. As the input shaft starts to rotate with vehicle forward movement, the stall torque ratio will become non-existent much sooner than a converter of the same stall, with a lower stall torque ratio." (Yank)
3)Shift Extensions. Pretty much the rpm's wont fall down as much between shifts. This also helps deal with the dead spots between gears (like a 45mph with 3.23's).
4)Weight- Aftermarket convertors weigh less and have less rotation mass.
What makes some torque convertors "loose"?
The greater the STR, the tigher the stall will be. For example a 3200rpm 2.2str stall will be looser than a 3200rpm 2.5str stall. Also, as the rpm rating increases, so does the "looseness". For example a 3600rpm 2.5str stall will be looser than a 3200rpm 2.5str stall.
What exactly is "loose"?
Throttle response. On a car with a loose convertor, you simply have to give it more gas to get the car moving.
What is it like to drive a high stall?
The best way to find out is to ask around and find someone local who will let you give their car a test drive.
There are some videos of stalls on youtube, but from my personal experience with my 3200 stall, it feels like the trans is slipping. My car revs up to around 3500 rpm and stays there for the 1-2 shift, 2-3, and 3-4 shift...when I hit 60km/h (city cruising speed) then it locks up and drives like normal. You can change your lockup times with hp tuners, but putting it lower then stock does put more stress the car...
What stall is the best?
Look into 3200-3500rpm stalls for street duty. Stick with the major brands, i.e. Percision Industries (Vigilante), Yank or TCI. Remeber, you get what you pay for.
Why do LS1's run higher stalls than LT1's???
It is the nature of the engine. To optimize preformance, you want to match the convertor to the engines powerband. The LT1 has great bottom end power where as the LS1 has an awesome top end so a higher stall is needed on the LS1 to optimize preformance.
Will the stall kill my tranny??
I do not know, Im not God. It will add more stress to the internals of the tranny because of the extra power that it produces. Some people have awesome luck with thier tranny, others, not so much
Do i need a tune??
Maybe. Some people have issues with the car hitting the rev limiter on shifts with a stall, a tune can correct this easily. Also, for the full effect, you might want to decrease/delete the torque management.
Will i have to rev the car to 3500rpm with my 3500rpm stall to get it to move from a stop??
Not even close. You just have to give it alittle bit more gas than on the stock stall. I watched my tach today and saw that the revs jump to about 1200-1400rpm to get the car moving from a stop.
Why doesnt my 3500rpm stall to brake stall to 3500rpm??
The convertor is not broken (lets hope), its just that your brakes arent strong enough or tires not sticky enough. If you have tried this, your tires just started spinning because your brakes simply cant hold the car still. You won't be able to reach this rpm unless you have a transbrake. A transbrake locks both forward and reverse gear at the same time which allows it to rev higher and doesnt rely on the brakes or tires.
Whats the best way to launch with a stalled auto??
Every car is different. You just have to play around with launching it at different rpms, brake stalling it or if the tires can gripe, just stomp on the gas pedal.
How much time will i drop??
For me, before the stall, my best time was 12.88@109. After the stall, it turned to 12.86@107 but i was launching soft and spinning, alot. I put on a set of e/t streets, and now run 12.36 @109. So it was a nice e/t reduction. A stall will make the car faster on the track as long as you can get traction.
Is it worth it?
For me, yes. It greatly dropped my times at the track. Its not a mod for everyone. You will have to give it more gas to get it to move around town. If your a speed freak, youll love it.
Should I get gears or a stall?
Try the stall first, it will give the biggest drop in e/t's. If you still want more, change gears.
What is the stock stall speed?
1800 RPM
Whats a 9.5inch stall?
Most aftermarket stalls are 9.5inch units. The stock stall is a 12.0 inch. The 9.5 is lighter than the 12.0 so easier to rev from reduced rotational mass.
Typical converter sizes:
300mm = 12" (stock LS1)
295mm = 11.5" (Stock GM)
245mm = 9.5" (stock 6/4 cyl)
(Thanks to 12secSS for the info)
I bought a XXXXrpm stall made by XXX and my track times suck now, what gives?
Most of the time, your mph will drop due to the stall being not as effecient as the factory one but if all goes right, your e.t. should drop. Check your 60ft time, more than likely your spinning the tires due to the stall transmitting large amounts of torque to the tires. To remedy this, get better tires and work on your launch. The first time you dead hook with a stall is awesome, pure and simple.
I am at the track. Should I shift the car myself or let the car do it?
Leave it in D or OD. You CANNOT shift faster than a computer. Some like to leave it in 3rd so it does not upshift to 4th when you let off. Others find the car shift betters in 4th if they have swapped gears (don't ask why the PCM does it)
Do I really need a tranny cooler with this stall.
Yes. As a by product of the stalling effect, more heat is created. This heat is damaging to the tranny and the way to deal with this is to get another tranny cooler(all Fbodies came from the factory with a external tranny cooler)
Do I need a shift kit with a high stall?
Unlike the cooler, a shift kit is not mandatory but its a good idea. The shifts with a stall might feel a little long so when you add the shift kit, the shifts quicken just a little more than stock.
Do I need a stall with a cam???
Usually. Most people tune the car for the cam which involves raising the idle speed on the car. Without a stall, you will have to just stand on the brakes to keep the car still because the engine is now idleing at 800rpm. Also, a bigger cam shifts the power band of the car higher, a stall enables you to jump into the cam's powerband faster so youll be faster.
What exactly does a high stall do?
1) Higher RPM Launches. This is self explanitory, but so is the search button so ill explain. You can brake stall to a higher rpm and also flash stall to a higher rpm.
2) Static Torque Ratio. I will leave the explaination of this to the experts at Yank
"The stall torque ratio is the amount of engine torque that the torque converter can multiply at a particular rpm level. By definition, stall torque ratio is when the turbine is at 0 RPMs and the converter is at maximum designed stall. This will produce a positive push on the turbine to increase the torque to the input shaft of the transmission, multiplied by the designed stall torque ratio of the torque converter. For example, a stall torque ratio of 2.0 would multiply 200 lb. ft. of engine torque to 400 lb. ft. of torque at the transmission input-shaft. The misconception of stall torque ratio is that more must be better. This is not always the case. High stall torque ratio applications, typically are for industrial equipment or engines with limited low rpm engine torque. With high stall toque ratio converters, there are important trade-offs. What you take at one end you give up on the other. Typically, a torque converter with a very high stall torque ratio, such as 2.0-2.5, will be much less efficient above its rated stall speed. There is a sacrifice in higher rpm efficiency to achieve high stall torque ratios. That lower efficiency translates into less horsepower transmitted to the tires over an RPM range. The problem with a high stall torque ratio converter is that it is only high while the car is not moving. Maximum stall torque ratio occurs at wide open throttle with no rotation of the transmission input shaft. As the input shaft starts to rotate with vehicle forward movement, the stall torque ratio will become non-existent much sooner than a converter of the same stall, with a lower stall torque ratio." (Yank)
3)Shift Extensions. Pretty much the rpm's wont fall down as much between shifts. This also helps deal with the dead spots between gears (like a 45mph with 3.23's).
4)Weight- Aftermarket convertors weigh less and have less rotation mass.
What makes some torque convertors "loose"?
The greater the STR, the tigher the stall will be. For example a 3200rpm 2.2str stall will be looser than a 3200rpm 2.5str stall. Also, as the rpm rating increases, so does the "looseness". For example a 3600rpm 2.5str stall will be looser than a 3200rpm 2.5str stall.
What exactly is "loose"?
Throttle response. On a car with a loose convertor, you simply have to give it more gas to get the car moving.
What is it like to drive a high stall?
The best way to find out is to ask around and find someone local who will let you give their car a test drive.
There are some videos of stalls on youtube, but from my personal experience with my 3200 stall, it feels like the trans is slipping. My car revs up to around 3500 rpm and stays there for the 1-2 shift, 2-3, and 3-4 shift...when I hit 60km/h (city cruising speed) then it locks up and drives like normal. You can change your lockup times with hp tuners, but putting it lower then stock does put more stress the car...
What stall is the best?
Look into 3200-3500rpm stalls for street duty. Stick with the major brands, i.e. Percision Industries (Vigilante), Yank or TCI. Remeber, you get what you pay for.
Why do LS1's run higher stalls than LT1's???
It is the nature of the engine. To optimize preformance, you want to match the convertor to the engines powerband. The LT1 has great bottom end power where as the LS1 has an awesome top end so a higher stall is needed on the LS1 to optimize preformance.
Will the stall kill my tranny??
I do not know, Im not God. It will add more stress to the internals of the tranny because of the extra power that it produces. Some people have awesome luck with thier tranny, others, not so much
Do i need a tune??
Maybe. Some people have issues with the car hitting the rev limiter on shifts with a stall, a tune can correct this easily. Also, for the full effect, you might want to decrease/delete the torque management.
Will i have to rev the car to 3500rpm with my 3500rpm stall to get it to move from a stop??
Not even close. You just have to give it alittle bit more gas than on the stock stall. I watched my tach today and saw that the revs jump to about 1200-1400rpm to get the car moving from a stop.
Why doesnt my 3500rpm stall to brake stall to 3500rpm??
The convertor is not broken (lets hope), its just that your brakes arent strong enough or tires not sticky enough. If you have tried this, your tires just started spinning because your brakes simply cant hold the car still. You won't be able to reach this rpm unless you have a transbrake. A transbrake locks both forward and reverse gear at the same time which allows it to rev higher and doesnt rely on the brakes or tires.
Whats the best way to launch with a stalled auto??
Every car is different. You just have to play around with launching it at different rpms, brake stalling it or if the tires can gripe, just stomp on the gas pedal.
How much time will i drop??
For me, before the stall, my best time was 12.88@109. After the stall, it turned to 12.86@107 but i was launching soft and spinning, alot. I put on a set of e/t streets, and now run 12.36 @109. So it was a nice e/t reduction. A stall will make the car faster on the track as long as you can get traction.
Is it worth it?
For me, yes. It greatly dropped my times at the track. Its not a mod for everyone. You will have to give it more gas to get it to move around town. If your a speed freak, youll love it.
Should I get gears or a stall?
Try the stall first, it will give the biggest drop in e/t's. If you still want more, change gears.
What is the stock stall speed?
1800 RPM
Whats a 9.5inch stall?
Most aftermarket stalls are 9.5inch units. The stock stall is a 12.0 inch. The 9.5 is lighter than the 12.0 so easier to rev from reduced rotational mass.
Typical converter sizes:
300mm = 12" (stock LS1)
295mm = 11.5" (Stock GM)
245mm = 9.5" (stock 6/4 cyl)
(Thanks to 12secSS for the info)
I bought a XXXXrpm stall made by XXX and my track times suck now, what gives?
Most of the time, your mph will drop due to the stall being not as effecient as the factory one but if all goes right, your e.t. should drop. Check your 60ft time, more than likely your spinning the tires due to the stall transmitting large amounts of torque to the tires. To remedy this, get better tires and work on your launch. The first time you dead hook with a stall is awesome, pure and simple.
I am at the track. Should I shift the car myself or let the car do it?
Leave it in D or OD. You CANNOT shift faster than a computer. Some like to leave it in 3rd so it does not upshift to 4th when you let off. Others find the car shift betters in 4th if they have swapped gears (don't ask why the PCM does it)
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