Swap Booster Options

[Jand3rson]

3 swap guys on R3V consecutively agree,

7 series boosters/masters are where it's at.

Yeah, with more modification, a different master cylinder (one more thing to buy), and you have to run lines and remotely locate your reservoir somewhere else.

The reason people feel like the E21 booster is "inadequate" is because it is. It's a smaller diameter and the same thickness as the stock E30 booster. The 944 booster is a smaller diameter, but is thicker, and has almost the same internal volume as the stock E30 booster. Uses the stock E30 master and reservoir, too. All you do is shorten and thread the pushrod, then it's a direct fit.

[uberm3]

Yeah, with more modification, a different master cylinder (one more thing to buy), and you have to run lines and remotely locate your reservoir somewhere else.

The reason people feel like the E21 booster is "inadequate" is because it is. It's a smaller diameter and the same thickness as the stock E30 booster. The 944 booster is a smaller diameter, but is thicker, and has almost the same internal volume as the stock E30 booster. Uses the stock E30 master and reservoir, too. All you do is shorten and thread the pushrod, then it's a direct fit.

I used the master cylinder that came on the booster E32. The reservior from an E12 cost $20.00 (located on the drivers strut tower) and the braided line was negligible.

[Jand3rson]

Just seems like more trouble than it's worth, to me.

The idea of remotely locating the reservoir turns me off to it completely, but I'm super-anal about aesthetics in my engine bay.

[gp.plus]

I used the 944 ATE booster, as janderson said you just shorten the pushrod and continue the threads further down to match the stock e30. However, I wanted to note that with my booster I had to slightly turn down the thickness of the shaft beyond the threads. I accomplished this by locking the Clevis end of the shaft (before cutting) in my drill and spinning it against sandpaper. I can elaborate if someone needs more info on doing this. I have not really come across anyone else having this problem, but there must be a couple versions of the booster out there.

[pandaboo911]

On a different thought, I have the Massive booster delete on my car and
the feeling is great (e30 m3 brakes with stock e30 master). If you choose
your master correctly the brake pedal has a very nice feel to it. Also
you get a lot more space under the hood.

With stock e30 brakes would you just downsize the master? I wanted to go this route but don't want a rock hard brake pedal.

[GunMetalGrey]

Ix booster, that's just a straight swap correct? Anyone have any opinion on that setup?

[ACHTUNG]

Ix booster, that's just a straight swap correct? Anyone have any opinion on that setup?

Yeah, I'm surprised no one has chimed in regarding the ix booster. It's a direct fit and no modification needed. This is what I went with.

Paging Fiddle007 to the white courtesy phone...

[GunMetalGrey]

Do you like it? Same feel as the stock setup I would think, and with no modifications, it couldn't be any easier! If anyone else has opinions on it, chime in!

[fronton]

I switch from m3 to a ix booster. worked great for 100 miles then just failed on me. Brakes are not assisted at all now. :( Don't know what I'll try next.

[Mr.SWISS]

Needs to be a double booster - believe they came out of the later 735i's. The early cars use a vacuum system from the power steering unit (which can also work but is more complex). When you pop the hood is pretty obvious as this latter system doesn't have a booster (just looks like a giant master bolted to the firewall).

And yes - this or IX booster (same thing basically) is the only way to go IMO. For the 735i - you need to use the pedal fork off of your stock booster to get the pedal height correct.

No.

For the pedal fork aka clevis, you NEED to order an ix clevis no matter what car you have!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!11

[Mr.SWISS]

I used the 944 ATE booster, as janderson said you just shorten the pushrod and continue the threads further down to match the stock e30. However, I wanted to note that with my booster I had to slightly turn down the thickness of the shaft beyond the threads. I accomplished this by locking the Clevis end of the shaft (before cutting) in my drill and spinning it against sandpaper. I can elaborate if someone needs more info on doing this. I have not really come across anyone else having this problem, but there must be a couple versions of the booster out there.

And that's a great way to tear the bladder and render your booster useless and create a massive vacuum leak that will drive you bananas. If you ever owned a 944 you would know they had whack ass brakes you could stomp the pedal and not get lock up. I have only first hand experience with having used a e21 on one car and an e32 booster and ix clevis on my E30S52. All of the problems and issues on swap one were solved or eliminated on this car. Wired up oil level sensor first thing!!!!! :pimp:

[gp.plus]

I agree there was a possibility to tear the bladder, so to clarify.. I spun the shaft very slowly and this was a very time consuming process. I also was sure to keep a small amount of lube in where the spinning shaft was touching to prevent any binding or overheating.

[aldur99]

is there a thread on how to swap the rod between the e30 booster and the e34/e32 double booster? I don't see how this done. The clevis from the e30 is easy to remove, but the e34 booster doesn't look threaded.

[e30s50dan]

IX booster (no bracket) ,e34 MC and res...easy..fits,and to me has the best feedback

My M3 with a 25mm MC still doesn't have the same feel as my 88IS S50 did...miss that!

[GunMetalGrey]

Alright, so I picked up an IX booster stupid cheap and I cannot seem to figure it out, if I run it without the bracket the holes do not line up, if I run it with the bracket obviously they line up fine. But the real problem seems to be the brake lines, the booster hits brake lines that run on the side near the strut tower, I have ABS and was wondering what you guys have done to make them fit.