Trans Brake

[Chilliwack 42]

I've got a question about trans brakes and their streetability. I know how they operate and how to race with one. As far as using one on the street can you down shift when coming to a stop or gear down when turning or going up a hill? Im rebuilding a transmission for a different project car and I'm debating whether or not I will get one. It will mostly be a race car, but I plan on driving it half an hour to the track and driving around town during the summer.

 

[viciousride]

Do you mean a full-manual VB? As far as I know, the trans-brake operation doesn't affect "street-ability". The transbrake is really only applied before launch, or when in reverse (on most applications). I owned a Foxbody with a C4 full-manual VB and TB. On the street I had no issues downshifting. However, I never downshifted at a high RPM.

 

[fin1]

The trans brake is not tied to normal street use (unless you are testing it). Shifting (up or down) does not involve the use the of the trans brake. Typically, it's set to engage/disengage off a separate switch that you activate at the line.

 

[Chilliwack 42]

It's a TH350 and it will be a full manual valve body with a trans brake. I know this should probably be in a Chevy forum somewhere, but I know a lot of people here know their shit. I've read somewhere that you have to remove the intermediate band and that there is no engine braking. Are you able to shift into second when slowing or coming to a stop? or will I have to brake in high gear and bump my shifter back to first once I've actually stopped? I know obviously when racing to leave it in high gear after the traps. Just not sure if I can downshift while on the street.

 

[Natural1]

You need to ensure that the transmission has been built to handle a transbrake and there is no intermediate band in a TH350. The valve body with the brake will just bolt up inplace of the old one but you will need a large cooler and a higher capacity pan.

FYI: The trans only activates the band (generally called the Low/Reverse band in other transmissions) in 1st and 2nd to hold RPM, in 3rd it will not. You will be able to upshift and downshift as you please and shift it to neutral after the beams. You will need a shifter with a reverse lockout, I use a B&M Pro Ratchet.

 

[spyder7724]

i used to run another car with a TH400 man valve body and TB and driving on the street (although it was very limited use) was fine. as said before the transbrake doesn't affect any of the shift functions but usually was only is available with a man valve body (that may have changed though). It holds pressure to the rev and low gear circuits at the same time to hold the trans shaft still and allow the converter to flash to it's maximum stall speed. I really like them and have been begging PA to let me test the prototype for the 5R55S but there seems to be some issues with the factory ECM when applied.
also go easy on the down shifting at higher rpms i remember my trans guy telling back them not to do that for some reason but can't remember why.

 

[Chilliwack 42]

Thanks for the info guys. I've upgraded some of the hard parts that I know are prone to failure like the input shaft as well as red alto clutches, kolene steels and a vaccu melt 300 sprag. I'm also running a deeper pan, trans cooler and the torque converter has an anti ballooning plate. I'm pretty sure it should be good for 600+ hp. I think I'll be returning the manual/automatic valve body I have and switching to a manual with a trans brake.

 

[Natural1]

You should be ok, then.