burnoutrpm

what the heck is the difference if any??? what is flash stall speed? is there any differeence between that and when you hold the foot brake and just stall it up??? how do iuse that to determine what stall to get???

AlkyIROC

Foot brake stall, flash stall and true stall are 3 different numbers.

Stall speed varies depending on many things. Amount of engine torque, weight of vehicle, altitude, etc. The same converter in 2 different cars will stall at different rpms. The rated stall speed is only a guess and should really be a rpm range.

Foot brake stall is usually low since the car's brakes can't hold back the torque of the engine. Flash stall is kind of hard to find. When you floor the gas, the rpm rill rise quickly before the car actually starts moving. It's that point when the rpm and the car starts moving that's flash stall.

True stall can only be found with the use of a transbrake. The transbrake locks 2 gears at the same time and prevents any power for going out the tranny.

My 8" converter is rated at 5700 stall. With the transbrake, my engine can stall the converter at 5000 rpm. If I had more torque it would stall higher. Although I never tried yet to see the maximum rpm but I know I can foot brake to at least 3500-4000 rpm.

A typical 2200-2500 street converter may only foot brake to 1800 before the vehicle wants to push through the brakes. It may also stall to 2800 depending on how much torque the engine is producing.

The best way to select the stall speed of the converter is to have the engine dynoed. Since many people can't do that your next best thing is to call the converter manufacture. They will want to know info on the car and engine and will suggest the best converter for your application.

DTL504

iTrader: (1)

My 2 part question is:
1. If you get a 3000 stall converter will your car move only when it reaches 3000 RPM. I dont want to be sitting at a red light and have to rev my car to 3000 RPM just to get it to move under normal driving conditions.

2. Will the car drive like a normal stock converter then once it reaches the 3000 RPM range it will flash and the car will take off like a rocket.

Which question explain how a stall converter respond on normal driving conditions.

AlkyIROC

Torque converters slip. They have to or the engine will stall. How much they slip is determined by the converter size and the stall speed. When a converter is at it's stall speed it's slipping the least. Typical stall speed is around 8% slip. The higher the stall speed the more the converter needs to slip at lower rpms. This slipping creates heat so tranny collers are required. An aftermarket cooler is recommended on any converter higher than stock.

Lockup converters eliminate this slipping by locking the 2 internal parts. A lockup converter will not lock in first gear or the engine will stall.

Just because the converter slips doesn't mean it doesn't transmit power. Even my car will move with just a light touch to the throttle. What the converter does is let the engine reach higher rpms quicker by slipping. Once the engine reaches those higher rpms, more power is transmitted through the converter.

Stoplight to stoplight driving will be normal however since the engine will gain rpm quicker you'll usually notice a decrease in milage at the lower rpms. Getting a higher stall converter is to allow the engine to operate in a different rpm range where it will do more work. When the engine is operated at rpms below the stall speed the converter just slips more but will still work. Again, all this slippage creates heat and excess heat is the number one cause of tranny failures. An external cooler is always recommended.

burnoutrpm

thanks for all the input ont the stalls flash sppeed im thinking of using a torkmaster 23-2500stall and needed some input on if the flash speed would effect the rated stall speed...


the last post was very informative to say the least....thanks again..any and all input is appreciated.:hail: