Footbrake vs. Transbrake

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DC 340 said:
Just so I can confirm I am dumb, a transbrake is used only with an automatic transmission, correct? For 4 speed guys, you are looking at a 2 step rev limiter for launch rpm control (or your foot) but it is still a footbrake race for us 4 speed guys, correct?
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Yep.
 
Thanks. So if I understand correctly...a 4 speed guy is at a disadvantage because the brain to foot signal/reaction is not as fast as the brain to finger/reaction on a button? Like I said I know next to nothing about a transbrake. I am stupid on it all.
 
B3422W5, when I used the FB, I left at 2000 rpm. Now with the TB, I started at 5200 and have tried 5600. Only difference is at 5600 rpm the car lifts a bit more. Runs the same as at 5200 rpm.
 
9secRR said:
B3422W5, when I used the FB, I left at 2000 rpm. Now with the TB, I started at 5200 and have tried 5600. Only difference is at 5600 rpm the car lifts a bit more. Runs the same as at 5200 rpm.
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what does the converter flash at?
 
Do you use a two step with the transbrake?
When I footbraked I never used a 2 step, but I did with the transbrake.
In my setup it was not all that differnt in the timeslip between the 2, but I could "tune" my reaction time by futzing with the 2 step RPM. I am not sure how everyone else approaches this, but I think there are probaly a few different ways to arrive at some consistency.
 
DC 340 said:
Thanks. So if I understand correctly...a 4 speed guy is at a disadvantage because the brain to foot signal/reaction is not as fast as the brain to finger/reaction on a button? Like I said I know next to nothing about a transbrake. I am stupid on it all.
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Imo, a stick guy can still cut a light on a full tree. On a pro tree, he is at the disadvantage you speak of. Then the stick guy has the problem of hooking up consistently. Lots easier to do with an auto trans.
 
My car would leave with the front tires on the ground off the footbrake. Flash Stall was around 4800. With the brake, it would wheelie about 8-9 inches, carry about 30ft, and hit 5200 against the brake.
I would stage, engage the brake, floor it at the first yellow, step off when the last yellow was full on.
Never used a two step.
 
DC 340 said:
Thanks. So if I understand correctly...a 4 speed guy is at a disadvantage because the brain to foot signal/reaction is not as fast as the brain to finger/reaction on a button? Like I said I know next to nothing about a transbrake. I am stupid on it all.
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A transbrake uses a solenoid to engage both first gear and reverse gear at the same time, locking the trans up solid. When the driver steps off the button, the solenoid disengages (as fast as possible) reverse disengaged, and the car takes off in first gear.
Kinda like a full throttle clutch dump in a stick car, and just as hard on driveline parts.
 
slant six said:
Do you use a two step with the transbrake?
When I footbraked I never used a 2 step, but I did with the transbrake.
In my setup it was not all that differnt in the timeslip between the 2, but I could "tune" my reaction time by futzing with the 2 step RPM. I am not sure how everyone else approaches this, but I think there are probaly a few different ways to arrive at some consistency.
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3 step. Burnout, TB, rpm limiter.
 
I couldn't begin to tell you why there's such a difference between the two styles of launching with your car. But it's about 5 hundredths difference between fb and tb on our AMX.
 
tvt59 said:
I couldn't begin to tell you why there's such a difference between the two styles of launching with your car. But it's about 5 hundredths difference between fb and tb on our AMX.
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only thing I can think of is I have a small cubic inch engine that the torque isn’t there to 60’ like a stroker has? I’m at 355”.
 
9secRR said:
only thing I can think of is I have a small cubic inch engine that the torque isn’t there to 60’ like a stroker has? I’m at 355”.
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NHRA 340 stockers with less motor than you have( and 400-500 pounds heavier) go mid 1.3xx 60 foot off( or quicker) the footbrake.
So it isn’t that.
Injected alky makes a lot of extra torque too
 
I cant see a purpose for a brake on a 727, if I was launching at 5500 rpm I'd have to shift to 2nd before the 60 foot line or I'd have the wheels up 8 feet high (this is my imagination of course).
 
With a 2 step, foot braking and line lock will a car hold at 3500 rpm or is it going to creep ?
 
MOPARMAGA said:
With a 2 step, foot braking and line lock will a car hold at 3500 rpm or is it going to creep ?
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Depends on the converter and also, if you are going to use line lock to hold the car at the line, then make it a 4 wheel line lock. That way you don't have to try and release the foot brake and line lock at the same time while trying to cut a light and stand on the skinny pedal.... lol
 
-Boosted- said:
Depends on the converter and also, if you are going to use line lock to hold the car at the line, then make it a 4 wheel line lock. That way you don't have to try and release the foot brake and line lock at the same time while trying to cut a light and stand on the skinny pedal.... lol
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Okay, thanks.
 
I haven't had much luck with my transbrake and radials. The only time using the brake it didn't go up in smoke was when I accidentally left in second, it still went 1.48 60'. It's been 1.34 foot braking leaving in low.
 
MOPARMAGA said:
With a 2 step, foot braking and line lock will a car hold at 3500 rpm or is it going to creep ?
Click to expand...
Without a two step (never used one) both cars can easily hold 3500 without creep. Both have around a 5k converter. Slow car has drums all around, 122mph, faster car (NOT fast!) has tiny factory girling discs and jfz's in the back, 132 mph. If im not running a
footbrake class, I always use the tb in the Tina.
 
I ask questions like that then I think, maybe I should just get my junk car done and try it out in my driveway lol
 
MOPARMAGA said:
I cant see a purpose for a brake on a 727, if I was launching at 5500 rpm I'd have to shift to 2nd before the 60 foot line or I'd have the wheels up 8 feet high (this is my imagination of course).
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With a brake, you need to build the rest of the drivetrain as if it were a stick. Without enough tire and traction to leave at 5k or above, imo a transbrake is not necessary.
(My 2300lb car has a glide/brake, 4"aluminum shaft billet 1350 yokes both ends, 9" with nodular center, spool, 4.57s, ladders, and14x32s. Maybe overkill, but I never broke anything but the converter).
 
B3422w5 said:
NHRA 340 stockers with less motor than you have( and 400-500 pounds heavier) go mid 1.3xx 60 foot off( or quicker) the footbrake.
So it isn’t that.
Injected alky makes a lot of extra torque too
Click to expand...
My car is 2700 lbs with me in it.
 
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