How bad is brake boosting?

[need new tires]

it has to do more with how long you are brake boosting. as far as how hard it is on parts i would venture to say it is easyer on the drive train then flat out smashing the throttle from a stop. atleast when BB you have already taking up all the slop in the drive train so you are shocking every thing less.

the main drawback is the heat that is caused by loading the tranny. as far as a rule that was said in school no more than 8-9 seconds to load a transmission due to the heat and internal stress.

side note: for the love of God put on an upgraded tranny cooler even if your car is stock.[/side note rant]

 

[noah89t]

:squint: hmm, brake boosting.. well at least I was under the impression it was used only by vehicles utilizing F/I. or was the bike boosted? I mean yes it has the potential to put load on anything, but I just didnt think it would make much of a difference on an N/A app.

gixxer750 is chris's screen name here like rob said. and his car is far from n/a

 

[Facime]

gixxer750 is chris's screen name here like rob said. and his car was far from n/a

:cry:

 

[noah89t]

:cry:

so true, but i did get a message from him yesterday about jzing his mkiii and leaving the mkiv alone.
i hope that wasn't a secret chris.

 

[Dylan JZ]

haha, please forgive me.. now that you mention it I know who you're talking about.. I just saw gixxer and was light ew bike.

 

[Poodles]

it has to do more with how long you are brake boosting. as far as how hard it is on parts i would venture to say it is easyer on the drive train then flat out smashing the throttle from a stop. atleast when BB you have already taking up all the slop in the drive train so you are shocking every thing less.

the main drawback is the heat that is caused by loading the tranny. as far as a rule that was said in school no more than 8-9 seconds to load a transmission due to the heat and internal stress.

side note: for the love of God put on an upgraded tranny cooler even if your car is stock.[/side note rant]

BINGO!

It's actually LESS stress ont he drivetrain as it's not a shock load. The tranny will be producing some heat, but if you have an upgraded tranny cooler like you SHOULD, then you'll be fine.

Doing it on the highway is another story, it's a tricky thing to do, but it takes the edge off of high HP N/A cars with instant torque...

 

[Big Rob]

There will only be an issue when the temperature of your transmission fluid rises above the safe operating temperature recommended by the manufacturer. If it does there will be lubrication issues in the transmission and THEN stuff will start failing.

Brakes don't care!
The engine doesn't care!
Your diff doesn't care!

Monitor your fluid temps and if they are going above specification you'll have to install a larger more efficient transmission cooler.

Rob

 

[suprahero]

Just be careful doing it because it becomes addictive. When my car was an auto, I would sit at red lights and do it for the hell of it. I know, a 1jz doesn't have enough torque do spin the tires, but somehow mine did. I would sit there and spin until the cars behind would be madder than hell, but they could never get up beside me to cuss me out, cause I'd be gone on green. After a while, my tires got bare, and my tranny didn't like me any more. I've promised myself I wouldn't do it to my wife's car. I added another stock oil cooler to her car for a little extra cooling power, but she won't be doing many burnouts.

 

[Nick M]

There are too many lies and rumors in this thread for anything to be taken serous.

You can hold the brake of an auto off the line with a good cooler. With the stock cooler, you will over heat the fluid, and loose clamping force of the clutch packs in the trans. This is why your car went slower if you tried it, and held it to long.

Stepping on the brake only slows you down when you are moving. No ifs ands or buts about it. Stupid ricers.

BZZZ! Wrong!

Brake boosting is cruising at 60 MPH or any set speed and pressing the brake and throttle to put a load on the motor and build boost.

I will be completely candid with you, cause why stop now. Quit posting any tech.

 

[Keros]

If your brakes are wicked hot (from a BIG stop), brake boosting at a stop may cause your pads to glaze. Also, if your brakes are new (under 500miles on them), brake boosting at a stop may cause glazing. Glazing, I believe, is when an outline of the pad is permenently imbedded in the rotor...

Other than that, I'd agree with Rob, the only part that would hate you is the torque converter. Being Jay and doing burn outs at stop lights is hard on everything connected to the wheels... a much different scenario than brake boosting.

 

[blackturbona]

rolling and doing it is what i always thoguht brake boosting was.

and if u maintain lets say 40 mph while boosting before take off in a race, how wouldnt that benifit you accelerate?

 

[supraguru05]

im going to try to summarize what has been posted here


im only going to talk about brake boosting as it partains to drag racing from a dig. not whatever this rolling stuff is

you can brake boost your car at the line it allows you to put load on your engine allowing you to get boost at the line. to verify this take your auto put it in nuetral and rev to like 3500 rpms and watch your boost gauge. next put it in D and put the brake on and rev it up a little bit (less that 6 seconds) and watch the boost gauge.

the load is taken by your brakes and torque converter. that is not to say your torque converter is under any oddly high levels of load it just allows your torque converter to exit stall and become fully engaged without the tires mocving. (that might not be true but thats how i understand a torque converter works it becomes fully engaged at higher loads). now that you have the torque converter out of stall the driveline is already adjusted taking up slack due to gear play but the torque converter is heating fluid up because it is loaded. this heated fluid is what can cause a problem hence upgrade your tranny cooler.


OR

if your serious about drag racing get a higher stall from suprarich to help get more rpms before the torque converter starts transfering the majority of torque to the wheels. and a upgraded tranny cooler


I belive most of this to be correct but if some of it is wrong or the terms are wrong just correct it

 

[Nocheez]

I'm fairly certain that the stall is the point where a torque converter can no longer absorb the power from the motor and starts transferring the power through the transmission. A higher stall will help you launch at a higher RPM at the track but can make driving on the street a pain. I'm sure those who are more knowledgeable will chime in and fix our crappy posts

 

[Nick M]

There is no fixing some of these posts.

I remember some airhead at the light one time. He took off, then disengaged the clutch, reved the engine high, and dumped it. The moron friends of his were all giddy. Why he didn't do that at the light will remain a mystery in the crevasse between his ears.

 

[Nocheez]

There is no fixing some of these posts.

I remember some airhead at the light one time. He took off, then disengaged the clutch, reved the engine high, and dumped it. The moron friends of his were all giddy. Why he didn't do that at the light will remain a mystery in the crevasse between his ears.

Jeez, that's bad. Probably not enough skill to launch his ricer car without stalling it.

 

[suprahero]

Being Jay and doing burn outs at stop lights is hard on everything connected to the wheels... a much different scenario than brake boosting.

:burnout:.......The only thing I ever had to replace was an auto tranny, but I did that twice before going to the five speed swap. I wish I'd just rebuilt my auto like I did my wifes with a kit from IPT.

I don't see how the tranny coolers can help that much if you're sitting still and brake boosting. It seems like air would have to be flowing over it to cool it off. I know it helps, but I can't see how it would help enough to keep from tearing up the transmission. I'm also a construction worker with a fifth grade education, so................

 

[Nick M]

No, you are right Jay. It heats that fluid something fierce. A better cooler will work, but airflow will make it work even better.

 

[Dylan JZ]

Nick I know this thread was ultra indecisive, but to say brake boosting does nothing from a roll is not entirely true. That is if youre racing on the streets like a tard.

When we were still building all motor VQ's, a few of our friends used to race around on the highways.. anyhow the guys with turbo cars that were racing would brake boost their SR's, CA's and etc with a decent sized turbo from a number of speeds and it most definitely benefited them to say the least.

Perhaps I missed your point.

 

[87supraturbo19]

I started this post with a manual in mind. I dont know were brake boosting a roll doesnt work came into play because it does. put your car in 1st or 2nd hold the brake until you get postive manifold pressure and release the brake. works great if you dont want rip your stock clutch a new one and run a v8 torque monster threw 1st and 2nd.

 

[NeedsAPorsche]

i don't know man...i recently raced against a friend's '07 Dodge 1500 Hemi pickup, and when i, "brake boost" we're usually at a roll from 15-MPH and i'm just lightly applying the brakes in the manual transmission, while applying the gas enough to build around 5-PSI so when we go, the turbo spools at a quicker rate since it's already spooling...*shrugs*