Trans Brake Tips

[340king]

I am helping a friend with a '70 Duster Drag car. We just installed a 904 with a Griner transbrake. My questions are:

1. What brake rpm limit should we use?
2. Where is the best place to mount the switch?
3. Do we still need to use any type of roll control during staging?

The car has a 360, 904 trans, stock trans ratios, 4.56:1 gears, 9.0X28.5 slicks, weighs 3,000 lbs w/o driver. The car ran consistent 11.7's @ 112 mph before the brake. Any advise would be appreciated.

[ROWDY]

i'd have to say on the shifter King...it's the easiest accessable place to have it(depending on the style of shifter

once you have finished with the line locker after the burnout there is no need for it when your in stage

[dart10]

I use a steering wheel button left thumb and the line lock on the shifter.you really need a 2 step to launch the car properly. I foot brake the car to stage and go to the brake button. the car wont move with the brake button depressed. the manufactors dont recommend launching over 4000 rpm for risk of damaging parts.your cars pretty light you could exceed that depending on traction, cam, convertor etc. you failed to mention your stall, 4400-5200 with a small block. Leaf springs are out with a brake. ladder bars and coil over are the way to go. good luck youll love comeing off the brake. Hold on. BOB

[carl]

we use a gringer brake and set the rpm's just above the peak torque of the motor's highest torque value rpm.

we mount our switches on the steering wheel.
just make sure that the cord has plenty of slack so as to turn the wheel and not get caught in the steering column. that has been a problem when using stock type columns.

you will not need to use the line lock with the trans brake.
carl
http://members.xoom.com/dustermocar/carl.html

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mocar or nopar

[AJ]

I would put the switch in a place that you don't bump it by accident. I have seen a tranny blown all over the track because he bumped the switch after the launch. Just my suggestion. AJ

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'98 Ram 4X4 V-10 '86 Daytona 498" Blown/Injected '71 Cuda 340 W-2 heads, 4 speed

[Belvedere]

I have always had the brake on the wheel by the right hand. Line loc went on the shifter or on the wheel by the left hand. My new box can use two buttons so they may both be on the wheel and put my line lock back on the shifter. Some guys like to put the launch just below the stall of the convert a couple of hundred rpm. I like to leave where it does the best. It's different for each car combination. Try different chips and track of the results. You do have a log don't you? Remember just one change at a time.

[340king]

Thanks for the replies. The button ended up on the thumb end of the shifter handle. We will try it there first. Our second option was the steering wheel.

We have a two stage box and were going to start at 3,000 rpm for the staged limit. The car has a Dynamic 8" convertor and stalls somewhere in the 4500-4800 rpm range.

We had hoped to go to Phoenix this past weekend, but mother nature said otherwise.

[Belvedere]

One more little thing... don't use just your thumb or finger to release your button. Use your whole arm. There are a whole lot more muscles involved in your fingers and it cause some inconsistancy in the release. If you close your fist and use the back side of a knuckle or tip of thumb, and yank your arm back like you are setting the hook in a large mouth bass,there is only a couple of muscle in your fore arm. The release is much quicker than your finger and more consistant. I know this sounds a little retentive but if you are bracket racing every little thing you can make more consistant makes a better race.

[supergoob]

I agree with Belvedere. The 340king needs all the help he can get. We are still trying
to keep him from driving in circles. ha. ha.
Personely, I think his head is to big for his shoulders.

[J-BODY]

Hey king! Clean the dirt off of that chassis, I think I know where we can get a Challenger body to hang on it. Lets go drag racing!!!

[SDDuster]

J-Body both of those guys need to work on their reaction time, and one needs to know how to turn on the fuel.

[340king]

I will say that I have never forgotten to turn on the fuel pump, and my red light times are some of the best, -.04 to -.06, so I wouldn't talk too much about it sleepy. That gas pedal must be real hard to push also.

One thing is for sure. We are all going faster together than we did on our own!

[Comp Chassis]

Mount your button where it is comfortable and where your arm is fairly extended. This will help you get off of it quicker and also help to keep you from leaning on it too hard.

With a 904, you probably want to see what max stall is and then chip it to about 400 rpm under max stall. To low a chip and the car will pop and bang real hard,not good on cranks, when it is set right, it should just sort of dance on the chip.

Word of warning, the 904 is not as bad as a 727, but, the Griner brake doesnt use low band apply so all of the hit is taken by the sprag. When it fails, the high gear drum goes to 3 or 4X engine rpm and the trans goes to neutral. You do the math. I was less than 10 feet from a 727 that let go. The shrapnel destroyed the trans shield, blew threw the floor and imbedded parts in the dashboard. When the guy got home, he found pin holes in his pant legs from pieces flying around.

Put a trans shield on it. Better safe than sorry.