Everything you wanted to know about brake boosters and master cylinders

[Van Westervelt]

So confusing after reading all this.

Looking to run a e21 320i booster. I have a 735i master cyl, although I dont know what size, and a 750i 25mm master cyl. I would like to use the 25mm one from the 750i with the e21 320i booster. Anyone have any experience or is anyone running this setup?

All my understanding says it will, but after reading, I am now confused

???

[browntown]

How about it i have seen them in European conversions ....i am going to try it...Should be cheaper than bmw.And direct fit!:p
Here is the link: http://www.e3024v.com/project6.htm

Dig it, seems like a good fit.

[djborya]

vw rabbit booster

How about it i have seen them in European conversions ....i am going to try it...Should be cheaper than bmw.And direct fit!:p
Here is the link: http://www.e3024v.com/project6.htm

[Van Westervelt]

So confusing after reading all this.

Looking to run a e21 320i booster. I have a 735i master cyl, although I dont know what size, and a 750i 25mm master cyl. I would like to use the 25mm one from the 750i with the e21 320i booster. Anyone have any experience or is anyone running this setup?

All my understanding says it will, but after reading, I am now confused

[equate975]

Does anyone have pics of a cut and welded IX booster to allow it NOT to have a remote res? I know I was talking to someone about doing it because I am 99% sure it would work, but I don't know anything more than that. I would really like to see the install pics if whoever did it, did it.

[e304lyfe]

Here's the e34 master cylinder, recommended by the op.

Here's a e39 master cylinder which I might be able to get on the cheap.

To me these look exactly the same, so the e39 one should work, right?

They are different.

[QuorumCAll]

He has a point. You can't rely on realoem.

yeah, and I can appreciate that, but there's no reason he can't be tact when making it.

[matt]

awsome contribution, just top notch

He has a point. You can't rely on realoem.

[QuorumCAll]

wow, you must be smart to go by a realoem drawing

awsome contribution, just top notch

[Mr Deagle]

Here's the e34 master cylinder, recommended by the op.

Here's a e39 master cylinder which I might be able to get on the cheap.

To me these look exactly the same, so the e39 one should work, right?

wow, you must be smart to go by a realoem drawing

[QuorumCAll]

Here's the e34 master cylinder, recommended by the op.

Here's a e39 master cylinder which I might be able to get on the cheap.

To me these look exactly the same, so the e39 one should work, right?

[golde30]

On a side note, I didn't tighten up or forgot to put my left top motor mount nut back on and the motor actually flexed up and was resting on top of the bolt on the motor mount and the car drove fine until I noticed it. So jacking it up a bit for spacers should be fine.

LOL. nice.

[kolunda]

On a side note, I didn't tighten up or forgot to put my left top motor mount nut back on and the motor actually flexed up and was resting on top of the bolt on the motor mount and the car drove fine until I noticed it. So jacking it up a bit for spacers should be fine.

[kolunda]

can a master cylinder from a 88 735i be used with the ix booster? either it wont or i dont have an ix booster because the holes are totally different

Yes. The 735i has the exact same booster as an ix and the same bolt pattern.

Just from my experience of fitting my s50 into my car with my booster...

First was an e21 320i booster, the pedal feel was crap and the car won't really stop. I don't know if the booster was just a crappy booster or what, either way it wasn't working. Had to shave some of the fins off the intake manifold to get it to fit. Went and bought a 735i Booster/MC before I knew I needed a remote resivoir and it fit fine after I shaved a few more fins off the intake but it wouldn't clear the intake and I didn't know at the time I needed a remote resivoir, but with a remote resivoir it will fit. I am now running for the time being my 318 booster which is about 1 inch bigger than a e32 320i booster, so I had to shave the intake manifold more and jack up the intake side of the motor and put washers to lift up the motor. The 318 booster has a much better petal feel than the 320i booster on the pedal but my 318 booster has a hole in it so I need to replace it. I was also having problems with my ABS pump so I just went ahead and ditched it and went with no ABS. I'm not able to lock the wheels up, but then again I have a hole in the 318 booster and the 320 never worked right with or without ABS.

[BDSax]

can a master cylinder from a 88 735i be used with the ix booster? either it wont or i dont have an ix booster because the holes are totally different