...in an ITA/H4 CRX?

My MG Midget, at 2000lb loaded, stops fine without one. Seems a CRX at 2175lb race weight should do as well.

Uhhh. Forget it. Just checked the rules after starting this post. Neither IT nor HC rules mention allowing removal of the booster, or allowing you to change the master cylinder for that matter.

 

The answer is yes anyway.
Try turning the check valve in the booster vacuum line around. Then try to stop the car. Hint... don't have anything in front of you when you try this.

 

...or shut the car off with it still moving

when I was looking at pre-built spec miatas, there was one that the owner said he disabled the power brakes. (illegality aside....) he said laptimes were instantly better, because with the light miata, drivers would overbrake the car.
now I personally dont have an opinion (or experience) either way, but just thought I would pass that along.

 

Perfect timing, I was going to post a similar question today.

This weekend at a Road Atlanta HPDE my instructor, a World Challenge guy, said my brakes were over boosted and suggested that I might try disabling my brake vacumn booster (with all the standard disclaimers, test with nothing in front of you).

He said that he likes disabling his brake booster on his race cars. You have to stand on the brakes to stop, but you feel like you're 'stopping' the car and can put more accurate pressure on your brakes.

I wanted to get peoples opinions on this and see if anyone did this or has tried this yet. Also, my brakes might be over boosted since I'm running a ITR EG with Cobalts, so it has a LOT of brakes.

 

Ewan, do you have ABS on your car? If so, then leave the booster.
If you remove the booster, better get a membership to the gym and start on your leg presses. Seriously, I know your car is light, but it's not 1600 pounds, which is what Heath McMillan's CRX weighs, and from what I have heard, his pedal pressure is somewhere on the stiff side of impossible.

 

madhatter and I tried this in his integra and the car simply would not stop. Rolling down the slight grade in front of my house with BOTH feet on the pedal... nothing.

Try at your own risk.

 

i agree,, the one on my ITA car failed.. Car didnt stop worth ****! It was like pushing in the clutch.. you didnt get any response.. so just leave it intact!

 

Wonder if there's any way to "restrict" the output of the booster, by 50 percent or so???

 

no.. but you could buy a smaller one = ILLEGAL tho

 

Miata 2200# - Works great without power brakes
Porsche 911S 2100# - Never had power brakes and works great
2400# Integra - Needed power brakes, but not full pressure

Use 2 2" pieces of flat stock with a nut and bolt at each end as a clamp. By adjusting this around the vacume line you can adjust feel and effect of booster, at your own risk. This works for race cars with racing pads, street cars need not apply.

 

I’ve never driven a car with a disabled brake booster, but like others I have rolled down the driveway with the engine shut off ! (What kind of cars does your instructor drive?)

Having said that I can’t understand what an over boosted, or “too” strong brakes should feel like. Taking rain, or a bad brake bias out of the question, is there such a thing as too much brakes? The stronger the brakes feel/are, the more often you can brake deeper and the easier you can pass someone more confidently. Roger Foo is a great example after seeing him at Road Atlanta not too long ago. It must really be interesting to drive a car that has its brakes too strong. So far in my limited experience it’s always been: if the brakes are good, brake harder!

 

I used to argue with Heath McMillian about the brake booster all the time. Every time he saw my car, he asked me why I still had it on there. Eventually, I gave in and removed it, and I'd never go back on a race car. The feel and consistancy is so much better without the booster! Yes, the pedal is a lot hard, but I barely weigh 130#, and I don't have any problems pressing hard enough. The main problem I have with boosters is that I left foot brake a lot, and would often run out of vacuum while braking and holding the throttle constant, then I'd lift the throttle a little and the vacuum would go up, causing the brakes to grab too much and over-slow me. Add a turbo to the mix, and it just got that much worse.
One thing to keep in mind is that the pedal is stiffer with the vacuum line removed than it will be if you remove the booster completely. There is a relatively big spring, and a fair amount of friction in the booster itself, so there is a difference in at least the feel between no vacuum on a booster vs. no booster at all. In any case, I find the car much easier to drive consistantly without the booster.

FWIW, my car is an 86 turbocharged Street Mod Civic that weighs 1910lbs.

-Chris

 

Brake boosters do not belong on real race cars.....period. You can not get consistent brake feel from corner to corner because of different amounts of vaccum in the chamber each time you step on the brakes. Hell, with a booster, there is no brake feel. The only cars on any track that have them are cars that are required to have them according to their rule book.

Before people complain about how hard it is to brake without it, you are not getting rid of it properly. The booster provides quite a bit of resistance if it is not supplied with vacuum. You have to get the thing right out of the car. If you find the car still too hard to stop you keep going one size smaller on the master until your little girly legs ( he he he) can properly heal and toe on the verge of lockup. (notice I didn't say "until you can stop the car")

PS- I love the sound tires make juuuuuuuuust before they lockup. Sounds like bacon frying to me. mmmmmm bacon

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EMod Civic &raquo;</TD></TR><TR><TD CLASS="quote">I used to argue with Heath McMillian about the brake booster all the time. Every time he saw my car, he asked me why I still had it on there. Eventually, I gave in and removed it, and I'd never go back on a race car. The feel and consistancy is so much better without the booster! Yes, the pedal is a lot hard, but I barely weigh 130#, and I don't have any problems pressing hard enough. The main problem I have with boosters is that I left foot brake a lot, and would often run out of vacuum while braking and holding the throttle constant, then I'd lift the throttle a little and the vacuum would go up, causing the brakes to grab too much and over-slow me. Add a turbo to the mix, and it just got that much worse.
One thing to keep in mind is that the pedal is stiffer with the vacuum line removed than it will be if you remove the booster completely. There is a relatively big spring, and a fair amount of friction in the booster itself, so there is a difference in at least the feel between no vacuum on a booster vs. no booster at all. In any case, I find the car much easier to drive consistantly without the booster.

FWIW, my car is an 86 turbocharged Street Mod Civic that weighs 1910lbs.

-Chris


</TD></TR></TABLE>

Ask Heath where he got the idea.

I haven't run it since I built my current SCCA car in 1991. You have to remove the booster and make a new push rod. A car with the engine off with a booster and a car without the booster are 2 different animals. In the Integras it's actually the booster which is flexing the most and not the firewall.

Yes, it takes more foot pressure but that's the built in ABS for you.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hracer &raquo;</TD></TR><TR><TD CLASS="quote">Â’ve never driven a car with a disabled brake booster, but like others I have rolled down the driveway with the engine shut off ! (What kind of cars does your instructor drive?)

Having said that I canÂ’t understand what an over boosted, or strong brakes should feel like. Taking rain, or a bad brake bias out of the question, is there such a thing as too much brakes? The stronger the brakes feel/are, the more often you can brake deeper and the easier you can pass someone more confidently. Roger Foo is a great example after seeing him at Road Atlanta not too long ago. It must really be interesting to drive a car that has its brakes too strong. So far in my limited experience itÂ’s always been: if the brakes are good, brake harder!
</TD></TR></TABLE>

I don't have ABS.

My instructor drives an E36 BMW. We got into the conversation because I was jerking the car a little during heel-and-toe downshifts. I've been working on being smooth, and have some work to do.

I've found that pedal setup is VERY important for smooth heel-and-toe'ing. I've started adjusting my gas pedal for my last two events and I've been much smoother. Before, I had to lift my foot (heel) up about two inches to get on the gas when my brake pedal was down -- you just can't not suck when you have to do that!

My instructor took my car out for two laps with me as the passenger and that's what prompted the conversation. The car got a little squirrely on him ... the back end tends to want to come out during braking if it's not straight. Something I've gotten used to and usually don't have a problem with. When I do start to build trail braking into my driving, I hope to take advantage of this behavior.

Normally I would just discount the conversation and work on my smoothness. Afterall, a good driver can drive any car well. Anyhoo, he does it on his E36, so I started considering it.

More than anything, I'm just curious as to what it would feel like to drive a car with manual brakes. I think I'll look into how much work it would be to remove the booster (and how easy it it to put it back) and then decide if I'm going to try it.


So it's illegal in many classes to remove your brake booster?!


Modified by SpiceyRice at 7:48 AM 9/24/2003

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Catch 22 &raquo;</TD></TR><TR><TD CLASS="quote">The answer is yes anyway.
Try turning the check valve in the booster vacuum line around. Then try to stop the car. Hint... don't have anything in front of you when you try this.

</TD></TR></TABLE>

Just had to bring this thread up again. I remember seeing it a long time ago.

This past weekend at CMP I was having more brake problems. Turned out the brake booster was malfunctioning and causing the brakes to lock up by themselves. For sunday we turned the check valve around disabling the booster.

It was signifigantly harder to press the pedal but not that bad. I did have to lengthen my braking distances. i don't know if it was because i was having to press down harder or the condition of the front pads/rotors being set on fire from saturday and having stock rear shoes on the car.

 

[QUOTE=ryan12321]

Just had to bring this thread up again. I remember seeing it a long time ago.

This past weekend at CMP I was having more brake problems. Turned out the brake booster was malfunctioning and causing the brakes to lock up by themselves. For sunday we turned the check valve around disabling the booster.

[\QUOTE]

Ahh that was your red civic sitting in the pits with the brakes locked and smooking.... gald you figured out what was wrong!

 

How do you mount the master cylinder if you remove the booster? Do you modify the brake lines and mount it right on the firewall?