Automatic Transmission 2-Speed thru 10-Speed GM Autos | Converters | Shift Kits
Sponsored by:
Sponsored by:

Trans brake and stall question!

Thread Tools
 
Search this Thread
 
Old 02-02-2009 | 11:25 AM
  #1  
oddwraith's Avatar
Thread Starter
TECH Fanatic

iTrader: (1)
 
Joined: Aug 2008
Posts: 1,283
Likes: 0
From: Canada
Default Trans brake and stall question!

Just wondering what the hell the trans brake is supposed to do? I have asked about this before but still am unclear. Any benefits of using it?

Also,

Would a stall (say 3200) help me do better from a roll and not just a dig?

thanks a bunch
Old 02-02-2009 | 11:30 AM
  #2  
tptransmission's Avatar
Closed ex-Sponsor Account
 
Joined: Dec 2008
Posts: 434
Likes: 0
From: Az
Default

Trans brakes lock the transmission up so the vehicle will not move when activated. The driver can then Give the vehicle as much throttle during staging to get the engine rpms up, without the vehicle moving.

Stall converters will help from a roll as well. It all depends on the RPMs you are at during the roll and the stall speed.
Old 02-02-2009 | 11:32 AM
  #3  
oddwraith's Avatar
Thread Starter
TECH Fanatic

iTrader: (1)
 
Joined: Aug 2008
Posts: 1,283
Likes: 0
From: Canada
Default

Originally Posted by tptransmission
Trans brakes lock the transmission up so the vehicle will not move when activated. The driver can then Give the vehicle as much throttle during staging to get the engine rpms up, without the vehicle moving.

Stall converters will help from a roll as well. It all depends on the RPMs you are at during the roll and the stall speed.

Ok, so when the driver is giving the throttle on staging, how does he get the vehicle to finally go when ready? (I assume the brakes will only hold for so much even with the t brake?)
Old 02-02-2009 | 12:07 PM
  #4  
tptransmission's Avatar
Closed ex-Sponsor Account
 
Joined: Dec 2008
Posts: 434
Likes: 0
From: Az
Default

Originally Posted by oddwraith
Ok, so when the driver is giving the throttle on staging, how does he get the vehicle to finally go when ready? (I assume the brakes will only hold for so much even with the t brake?)
A well designed tbrake will hold no matter what power you have. You don't use the brakes at all. T-brake are engaged using an electric switch of button, so you just release it when you want to launch.
Old 02-02-2009 | 12:14 PM
  #5  
sway99bird's Avatar
TECH Fanatic
iTrader: (22)
 
Joined: Jan 2008
Posts: 1,451
Likes: 2
From: Paris, Texas
Default

Thank you for the info i've been wondering the same thing
Old 02-02-2009 | 01:22 PM
  #6  
Circle-D's Avatar
FormerVendor
iTrader: (21)
 
Joined: Feb 2006
Posts: 2,474
Likes: 12
From: Houston, TX
Default

Just to clarify a little more on the inner workings, the transbrake is a solenoid activated by a momentary switch. The solenoid controls the reverse clutches. So when you are at the starting line you are in drive, push the button which engages reverse. So the transmission is trying to go both ways, in essence it is locked. Bring up the throttle to what you want to launch at and then release the button. Reverse clutches are disengaged and you go forward, really fast hopefully.

Chris

Last edited by Circle-D; 02-02-2009 at 01:31 PM.
Old 02-02-2009 | 04:20 PM
  #7  
FirstYrLS1Z's Avatar
TECH Veteran
20 Year Member
iTrader: (4)
 
Joined: Aug 2004
Posts: 4,177
Likes: 136
From: Euclid,Ohio
Default

Also,10 bolts disinegrate when subjected to a transbrake.The rearend is no longer 'loaded' as with a conventional auto trans and it sees the 'shock' similar to a stick shift.
Old 02-02-2009 | 05:02 PM
  #8  
HWI's Avatar
HWI
TECH Enthusiast
iTrader: (2)
 
Joined: Oct 2008
Posts: 586
Likes: 0
From: Florida
Default

Originally Posted by FirstYrLS1Z
Also,10 bolts disinegrate when subjected to a transbrake.The rearend is no longer 'loaded' as with a conventional auto trans and it sees the 'shock' similar to a stick shift.
I can attest to this, I saw firsthand someone annihilate their 10 bolt using a transbrake and it wasn't even a real high hp car, maybe 375-400hp.

Edit: They were running drag tires too, which didn't help the little 10 bolt any either.
Old 02-02-2009 | 06:18 PM
  #9  
FTICONVERTERS's Avatar
LS1Tech Sponsor
iTrader: (3)
 
Joined: Aug 2007
Posts: 1,352
Likes: 70
From: Deland, FL
Default

As others have said the transbrake locks it in two gears at the same time. It takes a special converter for this. It must have a large sprague or no sprague at all,an aftermarket stator,anti ballooning plates,furnace brazed and tig welded fins,haredened splines,etc. Most people use a two step rev limiter so when they are on the t-brake it holds the motor at a set rpm.When you release the button the two step goes to the high side chip. This gives you the hardest launches with the most consistency.You must have good driveline components for this. The converter must be built for your specific combination to make this work properly.

Greg
__________________
FTI COMPETITION CONVERTERS AND TRANSMISSIONS
"IT'S NOT CHEATING, IT'S THE COMPETITIVE EDGE."
1-866-726-8358
info@ftiperformance.com
FTIPerformance.com
FTI Converter build sheet

Old 02-02-2009 | 09:48 PM
  #10  
Chris Stewart's Avatar
Launching!

iTrader: (1)
 
Joined: Oct 2005
Posts: 231
Likes: 0
From: Spanaway, WA
Default

Originally Posted by FTICONVERTERS
Most people use a two step rev limiter so when they are on the t-brake it holds the motor at a set rpm.When you release the button the two step goes to the high side chip. This gives you the hardest launches with the most consistency.You must have good driveline components for this. The converter must be built for your specific combination to make this work properly.

Greg
That sounds awesome, I might have to try that...

Anyone here using a transbrake, that can give real results with/without the brake?
Old 02-02-2009 | 10:48 PM
  #11  
oddwraith's Avatar
Thread Starter
TECH Fanatic

iTrader: (1)
 
Joined: Aug 2008
Posts: 1,283
Likes: 0
From: Canada
Default

Originally Posted by tptransmission
A well designed tbrake will hold no matter what power you have. You don't use the brakes at all. T-brake are engaged using an electric switch of button, so you just release it when you want to launch.
Well I read "trans brake" under my hood somewhere, and have know idea about a switch? Damn, just reading this post myself really makes me feel like a newb.
Old 02-02-2009 | 10:53 PM
  #12  
oddwraith's Avatar
Thread Starter
TECH Fanatic

iTrader: (1)
 
Joined: Aug 2008
Posts: 1,283
Likes: 0
From: Canada
Default

Wow, I didn't know all of that. Thanks all for the clarification and help.
Old 02-02-2009 | 11:13 PM
  #13  
tptransmission's Avatar
Closed ex-Sponsor Account
 
Joined: Dec 2008
Posts: 434
Likes: 0
From: Az
Default

That why we are here until insane hours of the night, to insure you can be confident in finding the best way to remedy your problem. Well that and the chance to display our signature adds. lol
Old 02-03-2009 | 10:55 AM
  #14  
ShevrolayZ28's Avatar
TECH Addict

iTrader: (4)
 
Joined: May 2005
Posts: 2,318
Likes: 1
From: Massachusetts
Default

Good info here.

So when the trans brake is on and you floor the gas pedal, the car revs up to the converter's stall rpm but no higher?
Old 02-03-2009 | 11:06 AM
  #15  
FirstYrLS1Z's Avatar
TECH Veteran
20 Year Member
iTrader: (4)
 
Joined: Aug 2004
Posts: 4,177
Likes: 136
From: Euclid,Ohio
Default

correct,but,if you had a transbrake that stalled to 3000 under the situation you described and then you did some engine mods that increased the engine torque,the next time you tried your situation,the stall would be higher.
Stall is a function of resistance to engine torque.
Also that situation is building an incredible amount of transmission fluid heat.
Old 02-03-2009 | 10:04 PM
  #16  
tptransmission's Avatar
Closed ex-Sponsor Account
 
Joined: Dec 2008
Posts: 434
Likes: 0
From: Az
Default

You definitely do not want to sit on the stall to long. Especially with a loose converter. Heat generation is extreme.
Old 02-17-2009 | 08:37 PM
  #17  
cjg454ss's Avatar
Banned
iTrader: (27)
 
Joined: Jan 2006
Posts: 1,205
Likes: 0
Default

but do you go full throttle on the brake?
Old 02-17-2009 | 10:40 PM
  #18  
tptransmission's Avatar
Closed ex-Sponsor Account
 
Joined: Dec 2008
Posts: 434
Likes: 0
From: Az
Default

Originally Posted by cjg454ss
but do you go full throttle on the brake?
Transbrakes are designed to allow the driver to sit staged with out moving. As for the amount of throttle that all depends on your vehicle from a performance level and how you want it to launch. Also you have to consider the impact on the rear axle, drive shaft, when you do send that spike of torque.
Old 02-17-2009 | 10:44 PM
  #19  
calongo_SS's Avatar
10 Second Club
iTrader: (7)
 
Joined: Feb 2004
Posts: 2,070
Likes: 1
From: Victoria, TX
Default

You can depending on your combo. If your converter flashes to 5k on the brake and you can hook it then do it. Many will wire the brake and a 2 step together so the hit can be tamed down (or controlled) a little as needed. IE, converter flashes to 5k but the tires will only take 4k. Set the 2-step to 4k put the gas to the floor, let go of the button and hold on.

going with what tpt said, if you don't have a drive train that can take a beating I don't think you should be considering a brake. If you're using stock DS or rear end you're just asking to brake parts. a trans brake is for when you absolutely want the car coming out of the hole as hard as possible. that brakes ****.
Old 02-17-2009 | 10:50 PM
  #20  
tptransmission's Avatar
Closed ex-Sponsor Account
 
Joined: Dec 2008
Posts: 434
Likes: 0
From: Az
Default

Originally Posted by calongo_SS
You can depending on your combo. If your converter flashes to 5k on the brake and you can hook it then do it. Many will wire the brake and a 2 step together so the hit can be tamed down (or controlled) a little as needed. IE, converter flashes to 5k but the tires will only take 4k. Set the 2-step to 4k put the gas to the floor, let go of the button and hold on.

going with what tpt said, if you don't have a drive train that can take a beating I don't think you should be considering a brake. If you're using stock DS or rear end you're just asking to brake parts. a trans brake is for when you absolutely want the car coming out of the hole as hard as possible. that brakes ****.
Thanks and nice explanation.


Quick Reply: Trans brake and stall question!



All times are GMT -5. The time now is 11:04 PM.