Brake booster

[blancojp]

Are there and replacement booster/ master cylinder combinations that work with stock brakes and which fit in the stock location under the hood and nose of the car? This would require the least bit of modification.

When mounting on the firewall what kind of modifications are required to the pedal, linkage, etc?

You can also use a BMW E-30 type brake booster, it is slightly larger but it bolts right up to the existing location. The stock master cylinder bolts right up as well and gives a bit more boost than the stock unit.

[krewzer]

JP,
are you talking about using the BMW e30 booster with the Opel m/c, or both parts from the BMW?

[blancojp]

JP,
are you talking about using the BMW e30 booster with the Opel m/c, or both parts from the BMW?

BMW booster with Opel Master cylinder, works quite well and gives you a bit more boost since the BMW unit is 2" larger in diameter.

[roundl]

What year/make/model BMW booster would work?

Thanks,
Paul

[BDD]

And the BMW booster fits under the hood, nose, etc. with no modification (or eyesore cover)?
Do certain BMW master cylinders also fit in the GT with no modification?

These also bolt right on without drilling or angling new bolt holes, etc and the Opel master cylinder (and aftermarket versions) bolt to the booster with the same Opel m.c./ booster seal?

Is 1991 the newest Bmw booster, etc. that you are referring to?

Thanks.

[blancojp]

What year/make/model BMW booster would work?

Thanks,
Paul

I believe the E-30 era is from '80s to '90s or you can locate a booster from a BMW 325i.

I previously posted all of this on this forum, fits without modifying anything. You do however need to bang the inner fender well to allow for some clearance.

[hrcollinsjr]

I believe the E-30 era is from '80s to '90s or you can locate a booster from a BMW 325i.

I previously posted all of this on this forum, fits without modifying anything. You do however need to bang the inner fender well to allow for some clearance.

E30's from 1984 thru 1991 IIRC.

Harold

[73Manta72gt]

I'm looking for a few more details on the modifications needed to make the BMW booster work. What has to be modified beteen the E30 booster and the Opel master cylinder and between the booster and the rod from the brake pedal.

Thanks

Helmut

[hrcollinsjr]

I'm looking for a few more details on the modifications needed to make the BMW booster work. What has to be modified beteen the E30 booster and the Opel master cylinder and between the booster and the rod from the brake pedal.

Thanks

Helmut

Can't really help you with any real info but.... I believe they have a new Pull A Part in Winston Salem now. My BMW E30 would not be on the road today if it weren't for Pull A Part salvage yards. I have in it basically what it is worth and most of my parts were from Pull A Part. Talk about a rip off. Don't complain about Opel parts being high, they're cheaper than BMW parts and the cars are worth more when you're done.

You can check their car inventory on line but not what parts the cars will have on them. The Charlotte and B'ham yards have more than their fair share of BMW's.

Harold

[73Manta72gt]

A friend at work just paid $600 for a door panel because the interior of his 12 year old BMW is falling apart....40 year old Opel keeps going and going..:-)

[blancojp]

I'm looking for a few more details on the modifications needed to make the BMW booster work. What has to be modified beteen the E30 booster and the Opel master cylinder and between the booster and the rod from the brake pedal.

Thanks

Helmut

Hate to be like anyone else but the search function does work.

look at:

http://www.opelgt.com/forums/perform...ing-power.html

[73Manta72gt]

I saw that thread, but it doesn't give enough detail on what is required for the turnbuckle or linkage changes needed to make the BMW booster work with a stock master cylinder. I want to get some idea how deep the water is before I jump in and try the project.

If the parts are difficult to fabricate, it will make more sense for me to just replace the booster with a stock one.

[blancojp]

There are no linkage changes on this install. You get the booster, install it and set the turnbuckle just like the stock unit.

The turnbuckle is the easy part. The booster rod is threaded and the pedal rod is threaded. Knowing this, you create a part which has both threads that you need in order to couple the two rods together.

I have a few of those which I made for several members who wanted them. you can also make it yourself using the one from the Opel booster.

The rest is just banging the metal in the area where the booster mounts so it will clear the inner fender.

[73Manta72gt]

thanks i'm off to the u-pull-it yard with $15 for a booster

[73Manta72gt]

For the local North Carolina folks Greensboro Auto Parts (GAPCO) have a U-Pull-It yard across from the their service (high price) salvageyard. They have good prices with all part prices posted on the wall and everything is 1/2 price on Tuesdays and Thursdays. I got a 87 BMW 325i booster for $8. They don't have any Opels now but they actively recycle cars for scrap metal, so the inventory changes quickly.

[blancojp]

For the local North Carolina folks Greensboro Auto Parts (GAPCO) have a U-Pull-It yard across from the their service (high price) salvageyard. They have good prices with all part prices posted on the wall and everything is 1/2 price on Tuesdays and Thursdays. I got a 87 BMW 325i booster for $8. They don't have any Opels now but they actively recycle cars for scrap metal, so the inventory changes quickly.

Not to knock your effort but you should have picked up the M/C as well. The BMW M/C is lots better than the Opel unit and does have the outlet facing the right way.

What I would suggest you do is the following:
1) Remove the Hood and hood hinge so you can work comfortably. The 9" booster from a BMW is a very tight fit to put through the small opening from the radiator support to the edge of the body.
2) Remove old booster and start installing the new one. You will need to push the inner fender well about 3/4" towards the outer. This means you will hammer the section and check for fit until it goes in smoothly.
3) Cut the buckle off the old booster since you will refit to the new unit very easily. Take the lock nut from the new booster to a hardware place and get a drill and tap for the nut thread. Make sure the nut does not get lost in the trip.
4) Drill and tap the rod end side of the buckle you cut off from the old booster. Make sure you are able to screw in the buckle on the new booster's rod all the way in.
5) Screw in the lock nut and buckle to the new booster's rod. Lock the buckle in place at about 50% of full rod thread travel.
6) Install booster in place and start to rotate the rod as it meets with the brake pedal rod to thread in. Continue threading in the rod until it reaches the old lock position.
7) Install the four 13mm holding nuts with lock washers and torque to at least 15 foot/lbs. Check for smooth pedal travel, resolve if any binding is observed. This is very important, the pedal should go all the way down and all the way up smoothly.
8) Install vacuum hose, master cylinder and bleed the brakes. Once the brakes are tested OK, then replace the hood hinge and hood.

The above is what I did when I installed a 9" girling booster on my '72 GT. The results are quite good since you now increased your pedal boost from 340 to 572 psi @ 18" of vacuum.

Not a bad upgrade from a U-pick $8.00 purchase.

Let me know how it turns out.

[73Manta72gt]

The booster I got was a 11" Ate unit. It really looks massive. Is the girling booster only 9" I might have to go back and get the MC and see if I can make it work. I don't think I can make the opel booster work unless I have a remote fluid tank.

[blancojp]

The Girling 9" booster fits just fine with the stock master cylinder assembly. No need to go remote since it only moves the M/C forward 1/2".

The 11" booster is not an E30, it is an E35 and can't be installed.

[73Manta72gt]

I'm not familiar with the E30/35 designations. Is a 1987 325i a E30 or E35?

Any idea what models 325, 318, etc and years have the girling 9" booster? I have seen a few boosters on ebay but even the girling ones look like the bigger one I got off the 325i

off to the junkyard again..Thanks for your help.

[hrcollinsjr]

I'm not familiar with the E30/35 designations. Is a 1987 325i a E30 or E35?

Any idea what models 325, 318, etc and years have the girling 9" booster? I have seen a few boosters on ebay but even the girling ones look like the bigger one I got off the 325i

off to the junkyard again..Thanks for your help.

From Wikipedia:
The E30 was sold from 1982 through 1991 in sedan form, through 1993 in convertible form.

I do not believe this to be correct though. I believe the '84 model year was the first and it ran through at least '90 very possibly '91. My manual was printed early '91 and lists '84-'90. The 4 cyl. cars may be you best bet, '84-'85.

Check the car inventory online at your new Pull A Part in Winston-Salem. Charlotte for sure has several BMW's or did have.

HTH,
Harold