Effective in-vehicle torque converter stall speed is defined as the rpm the engine can reach with the brakes locked and the transmission in gear before the drive wheels turn . Converter stall speed must be high enough to put the engine into the torque range where it can most efficiently launch the car.
What is the stall speed of a stock torque converter?
Stock torque converters generally have a stall speed around 1,800-2,000 rpm . Higher stall speeds become necessary when horsepower and torque happen at higher rpm ranges.
What does a high stall torque converter do?
A higher stall torque converter will let your car accelerate better because the car will be taking off at the rpm range where it is making the most power.
How do you determine stall speed on a torque converter?
Ideally you want the stall to lock up somewhere close to the peak torque of the engine . Typically engines that produce more low-end torque will increase the stall speed. The same converter will stall at a lower rpm behind a less torquey – higher rpm engine.
What is increased stall speed on a torque converter?
What is Stall Speed? Stall speed is the speed at which the converter holds back or limits the engine speed if the transmission output is prohibited. When your torque converter prevents the power transfer from your engine to your transmission, it increases the engine’s RPM stalls .
What’s the difference between a stall converter and a torque converter?
A torque converter consists of three major internal components: the pump, turbine, and stator, as well as transmission fluid. ... A torque converter has three stages of operation: stall, acceleration, and coupling . Stall is when the transmission is in gear, but the brakes prevent the car from moving.
What is the difference between a low stall and a high stall torque converter?
For many street trucks that are used for towing, daily driving, and performance, owners choose a lower-than -stock stall converter. While high-stall converters are the ticket for racing, they generate lots of heat due to high slip percentages and can create a huge rpm drop when lockup is engaged.
What happens if torque converter stall is too low?
If converter stall speed is too low, the car will be lazy leaving the line ; if too high, there’ll be excessive high-gear slippage—either case adds time to your e.t. Engine builders use car weight and dyno data to aid selection. The converter is also matched to the transmission’s gear ratios.
What are the symptoms of a failing torque converter?
When the torque converter starts malfunctioning, you may feel shuddering and even slipping in overdrive . You usually notice your car shuddering because it feels like it’s vibrating. Your car will vibrate even when you’re not going very fast. The shuddering makes the car lag and is very noticeable.
Does a torque converter add horsepower?
An automatic transmission in general has a way of soaking up horsepower, but the torque converter can take a potent combination and turn it into a pig when the rubber meets the road. ... And while stall speed is important for a good launch, it’s also a place for horsepower to swirl down the drain.
Will a torque converter fill itself?
Unfortunately, many torque converters can only be refilled while the transmission is already out of the vehicle . However, you can refill some if they are equipped with either a lock-up torque converter or torque converter drain plug without removing them from the vehicle.
What causes torque converter failure?
Many torque converter failures can be caused by excessive friction , which means the torque converter’s needle bearings are damaged. Also, a faulty seals or faulty clutch solenoid can be to blame. A faulty seal can allow fluid to leak and become contaminated. A bad torque converter can damage a transmission.
What stall torque converter do I need?
For mild performance cars with something like a 350 HP engine, a 2,200 – 2,400 stall is about right. The basic rule of thumb is; if your engine “comes alive” at say, 3,500 RPM, then you want a stall converter with about 3,500 of stall to it.
How do you check a torque converter?
A rather simple test can determine whether the torque converter is failing. This is how to carry it out: Turn the ignition key and start up the engine . Wait for a few minutes for the engine to warm up, then gently press the accelerator twice and rev up the engine.
What does a lockup torque converter do?
Lockup torque converters are a type of converter that has a clutch. The engagement of this clutch causes the engine to lock to the transmission input shaft thereby leading to a direct 1:1 drive ratio .
