SWAP Thread: '91 325i Sedan - S50b30us

[328ijunkie]

I never run stock boosters or IXs on customer cars the boosters I use flushmount with the firewall and don't require remote resivors

[Mr.SWISS]

That's why I went with stock booster: Known braking power and effort, minimal changes to the hard lines, stock master to go with my stock calipers, and generally no worries about compromises in the system.

I think the ix booster is fine and I have had a swap car with an e21 modded boster before. Besdies, it was made like that from the factory in that configuration as well of course, and it clears the 24V.

[hwy84]

Would really suck to slam into the ass end of a Windstar because you got shitty brakes and lose it all.

I could not agree more. And epic choice on the Windstar in your example. Way more hilarious than a Town and Country.

In any case, I too consider brake operation critical. It really helps with my lap times. :)

That's why I went with stock booster: Known braking power and effort, minimal changes to the hard lines, stock master to go with my stock calipers, and generally no worries about compromises in the system.

However, I was under the impression that the linkage would work on the stock pedal bracket without binding. Since that is not the case, I am going to weld up a new bracket on the pedal arm that DOES line up. This will require drilling a hole into the passenger side of the pedal arm, to allow the pin to pass through it.

I realize this will weaken the pedal arm, however, I will be welding a big ass piece of steel to the side of it anyhow, which will negate the impact of the drilling.

The side of the pedal arm, thusly strengthened and built to snugly fit within the clevis of the stock booster rod, will perform exactly as the previous bracket did - using pressure from the steel bracket inside the clevis to compress the brakes, and only relying on the pin to pull the booster rod BACK when releasing the pedal.

Design and function will be no different from stock in any practical way, and I will retain the "belt and suspenders" approach that combines a shear pin with the clevis to ensure redundancy.

[Mr.SWISS]

Would really suck to slam into the ass end of a Windstar because you got shitty brakes and lose it all.

Order a treehouse booster or one from Dave (Markert MW) and make it right.

[hwy84]

If you move it closer to the drivers fender then you can arrange the clevis like i showed allowing it to be positioned perfectly straight. Yes the mounting to the pedal could use some work but it works ;)

EDIT: I made this work: http://www.r3vlimited.com/board/showthread.php?t=250474

Understood - Actually, my clevis WANTS to be where yours is pictured, but i angled it way over to the side to get it on the bracket.

I'll move it, and figure out a solution that will secure it in between the bracket and the arm... maybe zip ties.

Maybe.

;)

[328ijunkie]

If you move it closer to the drivers fender then you can arrange the clevis like i showed allowing it to be positioned perfectly straight. Yes the mounting to the pedal could use some work but it works ;)

[hwy84]

No i mean move it farther away from the manifold.

I apparently don't understand English - are you suggesting that I move the BOOSTER further to the driver's side of the car, or leave the booster where it is now, and move the CLEVIS closer to the driver's side of the car?

I assume you mean the latter ('cause the further I move the booster, without moving the clevis, the less aligned the rod will be with the booster).

That picture above is horrifying.

...However, I considered something like it, but with a hole through the pedal arm, and a lock pin/bolt through the entire assembly. Too stupid/unsafe?

[328ijunkie]

My car:

Booster shaft is straight as an arrow.


Ninja edit:
This is the reason i never use stock boosters on customer cars... GHETTO!

[328ijunkie]

No i mean move it farther away from the manifold.

[hwy84]

Its binding. Move the booster over more.

Bummer.

I have very little clearance between the booster and the intake manifold as it is (less than 10mm) - I can imagine that the engine could move enough on the mounts to contact the booster if I move it any closer, especially as the mounts wear over time. How close are people getting?

I only moved the booster 12mm (just under half an inch) - and others seem to have done this no problem... was there something else I should have done to make it work without binding?

I am curious to know how other "stock booster" folks dealt with the linkage...

Of course, I drilled new holes in the FW instead of slotting it, thinking it was going to result in more secure mounting. Now it just means less flexibility for moving the booster.

[328ijunkie]

Its binding. Move the booster over more.

[hwy84]

Brakes Drag - Pedal returns slowly

Nope, no binding or other issues with a relocated stock booster. feels just like it did before the swap.

Well, I have taken the car out for a couple shakedown runs, and my brake pedal is very slow to return.

With the car OFF, the pedal returns, but it is slow. Maybe takes literally an extra second to return the last inch of travel all the way to the top after I remove my foot.

With the car ON, the vacuum in the booster keeps the pedal from returning for much much longer, and the brakes drag.

My booster rod is attached to the stock mounting tab that is on the SIDE of the pedal assembly. This means the rod is angled. Is it possible that the angle in the linkage means the rod is dragging on something inside the booster, and that the return spring isn't strong enough to overcome that drag anymore?

How have other folks solved this booster issue? I imagine I could drill the pedal arm and put the clevis on the pedal arm itself, but that seems like it will weaken the pedal arm in a way I am not super excited about...

Any other thoughts on the slowness? I have bled all the air out of the system. I ran literally 2 liters of fluid through the system, and it is bleeding totally clean and free of bubbles...

[328ijunkie]

Pin 16 and 17 on the x20 are purely diagnostic for the e36. It's so you can plug into the diag port and talk to the abs, body control module, srs, etc.

[hwy84]

Glad you got it figured out!

Btw: Diagnostic 16 17 <- not needed. And wont really do anything.

Damn. How will my engine know if I have the flu? I was so hoping for rapid diagnosis. ;)

Seriously though, that isn't continuity from the Diagnostic connector to the ECU? I admit, I didn't delve deeply into it in the ETM, since I figured it wasn't critical to actually running the car...

<EDIT>

I think I answered my own question. Looks like X20 Pin 17 feeds diagnostic info to the OBC... which my E3 ain't got. Yes?

[328ijunkie]

Glad you got it figured out!

Btw: Diagnostic 16 17 <- not needed. And wont really do anything.