Stall/Torque Converter from SSP , in the real world?

[twasd]

hi there
I am trying to understand this specified Stall/Torque Converter from SSP.

https://www.maperformance.com/produc...fr-s-a960e-htq

I had A AT GT86
From my understnading , this item will raised 500-700 RPM above the factory setting.

I am assuming it have the following enhancement.

1. Harder and more fun lunch control

2. It will provide a better transfer of power to the drivetrain. It will not be gaining any horsepower, rather it will be recovering horsepower that would have been normally lost with the stock TC , however some said it only help to get few percentage hp back , so don't expect much on the new speed.

Is my understanding correct ? Please kindly correct me if I have misunderstanding.

Thank you very much.

[EndlessAzure]

Torque convertors always operate with some slip unless there is a mechanical shaft lock. When there is slip, the torque convertor and input shafts are spinning at slightly different speeds.

A special benefit of torque convertors is that when they are operating with very high slip (called the stall condition), they offer torque multiplication (like a mechanical gearing advantage). Torque delivered from the engine gets multiplied by a factor significantly more than 1:1 (usually ~2.5:1), resulting in a higher output torque to the gearbox.


However, torque convertors only really encounter stall when starting from a dead stop and within a certain RPM range above that. Therefore, if you can increase effective stall condition and increase multiplication RPM range, you can benefit for longer from additional mechanical advantage for launching the car, since you deliver more torque to the wheels.

Once the torque convertor is no longer in stall or acceleration condition, you no longer have torque multiplication. Torque input is much closer 1:1 to torque output to the gearbox.

• The final logical question is: why don't torque convertors always operate in stall mode if you get a performance boost?
• Answer: Excessive slip generates excessive heat, which will quickly overheat/breakdown the ATF and ruin the gearbox.

[twasd]

Originally Posted by EndlessAzure

Torque convertors always operate with some slip unless there is a mechanical shaft lock. When there is slip, the torque convertor and input shafts are spinning at slightly different speeds.

A special benefit of torque convertors is that when they are operating with very high slip (called the stall condition), they offer torque multiplication (like a mechanical gearing advantage). Torque delivered from the engine gets multiplied by a factor significantly more than 1:1 (usually ~2.5:1), resulting in a higher output torque to the gearbox.


However, torque convertors only really encounter stall when starting from a dead stop and within a certain RPM range above that. Therefore, if you can increase effective stall condition and increase multiplication RPM range, you can benefit for longer from additional mechanical advantage for launching the car, since you deliver more torque to the wheels.

Once the torque convertor is no longer in stall or acceleration condition, you no longer have torque multiplication. Torque input is much closer 1:1 to torque output to the gearbox.

• The final logical question is: why don't torque convertors always operate in stall mode if you get a performance boost?
• Answer: Excessive slip generates excessive heat, which will quickly overheat/breakdown the ATF and ruin the gearbox.

Thanks a lot for the answer , it really explain in a nice and clear way.

I really like the way you high light the impact , the ATF overheat , and the potential risk for the gearbox.

According to the SSP web site , the twins have a factory stall of 2540+/- 150 RPM , and their SSP A960E will raise 500-700 RPM. I did a quick math , that means possible 2890-3390 rpm for the stall condition.

Does it mean , if I consistently keep my engine running in high rpm , let's say 4000-7000 RPM , I won't feel the advantage from such aftermarket Torque Coverter ?

Is my understanding correct?
Again , thanks for the nice explanation.

[EndlessAzure]

Originally Posted by twasd

Thanks a lot for the answer , it really explain in a nice and clear way.



I really like the way you high light the impact , the ATF overheat , and the potential risk for the gearbox.



According to the SSP web site , the twins have a factory stall of 2540+/- 150 RPM , and their SSP A960E will raise 500-700 RPM. I did a quick math , that means possible 2890-3390 rpm for the stall condition.



Does it mean , if I consistently keep my engine running in high rpm , let's say 4000-7000 RPM , I won't feel the advantage from such aftermarket Torque Coverter ?



Is my understanding correct?

Again , thanks for the nice explanation.

I'm sure there will be some benefit, but I have no idea how much.

[EvilPenguin04]

So with a higher stall it's easier to get the car to launch it won't really affect anything in the upper RPM since the stall is the point the tires break loose using brake and accelerator or transbrake. If you are not going to drag race the car it isn't worth it IMO.