not looking to get one, but im curious how they work. anybody have an article i can read or be able to give me a detailed how to sorta thing? My best guess is that there is some kinda valve that opens to bypass everything but when closed it makes it all work again? something to that effect maybe? no idea just guessing.

 

its basicly a modded valve body and what it does is put the tranny in 1st and reverse at the same time

 

Basically, a transbrake engages the reverse circuit at the same time the transmission is in first gear. This locks the transmission in 2 gears at once and no power can go out the tailshaft. Since the transmission is locked, the engine rpm can be increased up to the converter's stall speed. When the transbrake is released, the fluid is dumped from the reverse circuit and the car launches forward at a high rpm. Because of how the valve body is designed, the transbrake will only work in first gear.

My converter will stall at 6000 rpm on the transbrake. I set my 2 step to 4500. When I push the transbrake button and put the throttle to the floor, the engine rpm will only go to 4500. When the transbrake button is released, the car launches at the preset rpm and quickly climbs to 6000. After a shift at 7400 rpm, the rpms only drop to 6400 rpm until I cross the finish when they're back up to 7400 rpm. I can change my launch rpm with the 2-step the same as a manual transmission car can change the launch rpm before releasing the clutch but a transbrake equipped car can only increase the launch rpm up to the converter's stall speed. Without a transbrake, you'll never know what the converters true stall speed is.

A transbrake is more than a simple valve body swap. It also involves tearing down the transmission to do some internal modifications.

There is no function for a transbrake on the street. It's a race only item.

 

i got a t-5 anyway in my car. i was just trying to figure them out. i was at least on the right track with it messing with fluid flows. Sounds like something like that would be somewhat hard on a tranny?

 

Tranny, no. Driveline, yes.

If you're at full stall for very long, the tranny oil gets hot quickly which is bad. Although all drag racing is hard on transmissions, a transbrake itself does little if any damage to the tranny.

When the transbrake releases, the shock to the driveline can cause damage. 1350 series u-joints, a good strong driveshaft and a strong differential can take most of the shock but even they can fail.

When I launch at 4500 rpm, my engine is around it's peak torque when the transbrake releases. It's not a slow build up like accelerating from an idle. I'm letting approximately 750 pounds of torque into the driveline instantly. Good for those wheels up launches and quick 60' times.