Brake booster delete???

m5bb

m5bb

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Has anyone tried running brakes without a brake booster?
I am working on the great weber install and therefore booster change.

I have a friend that has a 2002 race car and does not run a booster but does have a bigger master which I could easily do to and E9.

Also looked at some after market hydro boost systems which sure would eliminate the space problem.
www.hydratechbraking.com/Universal.html

Any suggestions or experiences?

Thanks,
Gary
 
Thanks Jay,

That makes sense and I actually did some further searching and found more info.

So still not sure if it would be possible to run without a booster.
I think our masters are 21 or 22MM?
 
I would have thought it would be possible, it would be the same as the race cars. I think the problem would be the extremely heavy pedal that they have to achieve the same braking effect - which is fine in a race car but annoying on the road.
 
I was going have the hydraulic booster system from an e28 installed in my coupe when I was considering using ITBs. Unfortunately, the shop that did the swap botched the job (among many other things) and when I took my car to competent mechanics, I was advised against using the system as there was no advantage other than the space it freed up (by this point I dumped the idea of using ITBs as well). I think if you do a search, there is a member of the board who has done this swap. So, bottom line, it can be done, just find the right people ; maybe SfDon can weigh in.

I am also considering going the 3x Weber route and was concerned with brake booster clearance. In a conversation with Korman BMW, I was told that you should be able to use the "fly eye" filters with the standard brake booster. All you have to do is put a small dent in the bottom right portion of the center filter (unseen when looking from above).

Good luck with your project, keep us informed.
 
It's interesting that you mention the Massive Brakes guy Lee because this is what brought this up. A friend found this and mentioned it to me.
Thanks


decoupe said:
Gary;

I asked Lee at Massive Brakes - a BMW brake guru - about this and some of his comments can be found in the first link.

http://www.e9coupe.com/forum/showthread.php?t=12709

An example of a boosterless pedal box for the e30 he supplies is in the second link below.

http://www.e30tech.com/forum/showthread.php?t=118323
Click to expand...
 
Hey Gary !

this wouldn't be apples to apples but my race cars have dual masters that are boosterless . We matched the cyl size to the piston size . the pedal feel is perfect , the pedal isn't too hard at . It feels quite similar to a car with a booster. Like you I was quite worried about the pedal being to firm, but it actually worked out great



BD
 
Race cars have twin masters because they usually have an adjustable balance bar that allows them to adjust the front to rear brake bias for different tracks or even during a race because as fuel is burned up the balance of the car may change. Many race cars have a brake bias adjustment knob mounted right on the dash or some other convenient spot.

Generally speaking race cars don’t need boosters because they have massive multi piston calipers with much larger (in square inches) brake pads…….. there is so much pad area that not as much pressure is needed to drag the car down in speed. Pressure boosters allow a more minimal brake system to work quite well on a street car even with a small woman driving it, not that there is anything wrong with smaller women, they can be nice too :-D. ~ John Buchtenkirch
 
Hi Gary .

Im not sure this picture will help you , and as I said earlier its not apples to apples

chris%2527s+pics+1034.jpg


if you want to come downtown and see that set up shoot me an email


Brendan
 
Have you looked into anything like this?
www.hydratechbraking.com/Universal.html

There are a number of these systems on the net.


Ohio Jon said:
I'm running into the same space issue with my S38 swap. I have decided to use the hydro boost set up from a E23 7 series.
http://realoem.com/bmw/showparts.do?model=6633&mospid=47190&btnr=34_0267&hg=34&fg=25
From my personal experience manual brakes on the street are no fun. They require too much effort. On the track I have not had a problem. The adrenaline helps.
Click to expand...
 
So you must be in Atlanta?
Would love to see what you are building.
There are a couple of 3.0 track cars being built in the area.
Gary

bdigel said:
Hi Gary .

Im not sure this picture will help you , and as I said earlier its not apples to apples

chris%2527s+pics+1034.jpg


if you want to come downtown and see that set up shoot me an email


Brendan
Click to expand...
 
Ohio Jon said:
I'm running into the same space issue with my S38 swap. I have decided to use the hydro boost set up from a E23 7 series.
http://realoem.com/bmw/showparts.do?model=6633&mospid=47190&btnr=34_0267&hg=34&fg=25
From my personal experience manual brakes on the street are no fun. They require too much effort. On the track I have not had a problem. The adrenaline helps.
Click to expand...

Oh, the bomb. I have it in the E24, it works great. I had to replace it once since 1987, not bad.
 
m5bb said:
So John and BD. How were two masters set up?
Any photos?

Gary
Click to expand...

The first photo is of a balance bar that another crafty member made up for his race coupe. The second photo is the smaller in diameter TII booster in a coupe. IMO a balance bar isn’t by any means the cure for hard brakes caused by removing the brake booster, it’s basically just for adjusting the front axle to rear axle brake bias. ~ John Buchtenkirch
balance bar in a coupe.jpg

BMW TII booster installed.jpg
 
Some of the E30 guys that swap their motors use Geo Metro boosters, older Audi units, and I believe some of the older VW boosters. If the bolt pattern is the same among E30s and the E9/E3, those could be easy to use alternates also. From what I remember, the only changes are to the rod that comes out of the booster and connects to the pedal.
 
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