Please explain the use of a "stall convertor".
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Re: Please explain the use of a "stall convertor".
All torque convertors have a stall, it keeps the engine from stalling when stopped. Stock the stall speeds are low around 800rpm. Higher stalls are used to get the engine up in rpms before putting full torque to the driveline. Matching stall speeds to engine characteristics gives good launch from the line without bogging until RPM's get into power band. That is an overview, someone else will have to jump in with more specific info. I don't have one in my Nova
All torque convertors have a stall, it keeps the engine from stalling when stopped. Stock the stall speeds are low around 800rpm. Higher stalls are used to get the engine up in rpms before putting full torque to the driveline. Matching stall speeds to engine characteristics gives good launch from the line without bogging until RPM's get into power band. That is an overview, someone else will have to jump in with more specific info. I don't have one in my Nova
Re: Please explain the use of a "stall convertor".
I guess using my stock convertor is fine...for now. Will I be able to see a difference if I upgraded to a higher stall? The nova is used only as a weekend ride, with very minimal upgrades.
I guess using my stock convertor is fine...for now. Will I be able to see a difference if I upgraded to a higher stall? The nova is used only as a weekend ride, with very minimal upgrades.
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Re: Please explain the use of a "stall convertor".
You really only need to change to a higher stall if you do enough modifications to your engine that it moves your power band up in the RPM range. Small little bolt on upgrades like headers, MSD ignition, Carb, Fuel pumps, and high flow water pumps are not going to have an effect. If you start changing cam, heads, intake, or complete engine overhaul with different pistons, head shaving... will cause you to start looking into stall. A lot of high performance engines can't idle down low or when they get to a certain point the torque of the engine drops significantly causing it to bog out the engine at low RPM.
You really only need to change to a higher stall if you do enough modifications to your engine that it moves your power band up in the RPM range. Small little bolt on upgrades like headers, MSD ignition, Carb, Fuel pumps, and high flow water pumps are not going to have an effect. If you start changing cam, heads, intake, or complete engine overhaul with different pistons, head shaving... will cause you to start looking into stall. A lot of high performance engines can't idle down low or when they get to a certain point the torque of the engine drops significantly causing it to bog out the engine at low RPM.
Re: Please explain the use of a "stall convertor".
Thank you for the information. I will be installing a mild cam, (204/214), rebuilt heads, shift kit, and a locker in a few months. So I guess the best thing to do is to wait and see how it runs. It will save me a little time and money if I don't need the stall.
Thanks.
so-cal Jack
Thank you for the information. I will be installing a mild cam, (204/214), rebuilt heads, shift kit, and a locker in a few months. So I guess the best thing to do is to wait and see how it runs. It will save me a little time and money if I don't need the stall.
Thanks.
so-cal Jack
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Re: Please explain the use of a "stall convertor".
How do you know if you have a "stall converter"? My car was built by a guy to race - and then it was "cleaned up" to the present street/strip combo it is now. It has a pretty potent 396 in it and a lot of other goodies that make me think it should have a stall in it. I have not had one so I don't know what to look for. I have noticed that when standing on the gas from a dead stop it goes 10 feet or more and then breaks the tires loose. I don't think this is a tranny problem as it is built also. If it does have a stall in it - do you just power brake the car up to 2500 or so and then let off the brake to launch it??
How do you know if you have a "stall converter"? My car was built by a guy to race - and then it was "cleaned up" to the present street/strip combo it is now. It has a pretty potent 396 in it and a lot of other goodies that make me think it should have a stall in it. I have not had one so I don't know what to look for. I have noticed that when standing on the gas from a dead stop it goes 10 feet or more and then breaks the tires loose. I don't think this is a tranny problem as it is built also. If it does have a stall in it - do you just power brake the car up to 2500 or so and then let off the brake to launch it??
Re: Please explain the use of a "stall convertor".
You definitely have a stall converter, Racinfan, cuz if you didnt, itd die every time you stopped. Think of it as having a manual transmission with no clutch...every time you rolled up to a stop sign in first gear, being direct drive, as you came to a stop, the engine would bog down and die without a stall converter. The SC is kinda comparable to a clutch in many ways and the amount of stall = at what point, RPM-wise, that you release the clutch fully, if that makes any sense (Ive never been very good at explaining things :clonk: ).
You definitely have a stall converter, Racinfan, cuz if you didnt, itd die every time you stopped. Think of it as having a manual transmission with no clutch...every time you rolled up to a stop sign in first gear, being direct drive, as you came to a stop, the engine would bog down and die without a stall converter. The SC is kinda comparable to a clutch in many ways and the amount of stall = at what point, RPM-wise, that you release the clutch fully, if that makes any sense (Ive never been very good at explaining things :clonk: ).
Re: Please explain the use of a "stall convertor".
The reason you go ten feet before breaking the tires loose is because it takes that amount of time to get the engine up into it's power band were it then generates enough torque to overcome the static friction of the tires. There is nothing wrong with your set-up from an engine transmission point of view.
If you find the tire smoking thing unacceptable; it is time to make the suspension work. By transferring more weight to the rear and planting your tire, and controlling engine torque with a CalTrac or similar traction bar you will limit wheel slip; larger stickier tires wouldn't hurt either. Just be prepared for something else to break when traction isn't your weakest link.
Big Dave
The reason you go ten feet before breaking the tires loose is because it takes that amount of time to get the engine up into it's power band were it then generates enough torque to overcome the static friction of the tires. There is nothing wrong with your set-up from an engine transmission point of view.
If you find the tire smoking thing unacceptable; it is time to make the suspension work. By transferring more weight to the rear and planting your tire, and controlling engine torque with a CalTrac or similar traction bar you will limit wheel slip; larger stickier tires wouldn't hurt either. Just be prepared for something else to break when traction isn't your weakest link.
Big Dave
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Re: Please explain the use of a "stall convertor".
I currently have 205 70/R14's on it, so the tire smoking thing is kinda unavoidable, and is actually entertaining....LOL
The car has traction bars and frame connectors, I also got a set of 8" slicks with it. Once I get it tuned properly I want to run it at the strip once or twice just to get a time slip and see what she will do. I was just wondering because I can power brake it up to about 2300 rpms before it wont hold w/the brake anymore and then it is instant light up.....
I currently have 205 70/R14's on it, so the tire smoking thing is kinda unavoidable, and is actually entertaining....LOL
The car has traction bars and frame connectors, I also got a set of 8" slicks with it. Once I get it tuned properly I want to run it at the strip once or twice just to get a time slip and see what she will do. I was just wondering because I can power brake it up to about 2300 rpms before it wont hold w/the brake anymore and then it is instant light up.....
Re: Please explain the use of a "stall convertor".
Is there a way to manually figure the stall that is currently in my car? Someone told me to stand on the brake.....while stepping on the gas. When the wheels start to break loose, is approximately the stall of the convertor. This will be hard for me, since I have manual brakes. Is there another way?
so-cal Jack
Is there a way to manually figure the stall that is currently in my car? Someone told me to stand on the brake.....while stepping on the gas. When the wheels start to break loose, is approximately the stall of the convertor. This will be hard for me, since I have manual brakes. Is there another way?
so-cal Jack
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Re: Please explain the use of a "stall convertor".
Others report you'll get a close estimate by nailing the gas (WOT) while watching the tach. The RPMs the tach displays before the car starts to move should be close to your converter's stall speed.71Nova400 said:
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