M50 swap that will blow your mind.

[jc1000]

I can't say I've had a point of reference to compare; I mean I don't know how the brakes would feel if I didn't have the proportioning valve. I've kept it the way BMW intended it, but, they designed it to be used with the original master cylinder, sooo... maybe there will be a difference. I don't know exactly how much that valve alters the flow rate of the brake fluid to the rears, and I don't know if the E90 master has that "value" incorporated.

I think in order to get rid of it, you'd have to extend the lines with unions to be able to reach the master.
Getting rid of the valve doesn't reduce the number of connections unless you run entirely new hardlines to the master.

I did have to alter the bends of the existing lines to get the proportioning valve to sit correctly. So either way, you are bending the lines.

I haven't experienced any "unusual" feelings regarding the brake bias with this setup. I have braked hard and felt the ABS engage, and any spirited driving I've done hasn't caused unpredictable trail braking/understeer. So. I'll just say the system works fine as it is.

Fair enough, thanks. I think I will give keeping it a try for now.

[Chilezen]

Hey Chilezen! I am doing the E90 swap now and have ABS and the proportioning valve. Would you recommend keeping the proportioning valve?

I can't say I've had a point of reference to compare; I mean I don't know how the brakes would feel if I didn't have the proportioning valve. I've kept it the way BMW intended it, but, they designed it to be used with the original master cylinder, sooo... maybe there will be a difference. I don't know exactly how much that valve alters the flow rate of the brake fluid to the rears, and I don't know if the E90 master has that "value" incorporated.

I think in order to get rid of it, you'd have to extend the lines with unions to be able to reach the master.
Getting rid of the valve doesn't reduce the number of connections unless you run entirely new hardlines to the master.

I did have to alter the bends of the existing lines to get the proportioning valve to sit correctly. So either way, you are bending the lines.

I haven't experienced any "unusual" feelings regarding the brake bias with this setup. I have braked hard and felt the ABS engage, and any spirited driving I've done hasn't caused unpredictable trail braking/understeer. So. I'll just say the system works fine as it is.

[jc1000]

It's a proportioning valve only on those models/that year. I have the same. Some people get rid of theirs. I went through the extra effort to bend the lines and relocate it to underneath the master, positioned horizontally. See my post above, you can baaarely see it hidden under there. I'll try to get a better photo soon.

Hey Chilezen! I am doing the E90 swap now and have ABS and the proportioning valve. Would you recommend keeping the proportioning valve? Why do people get rid of it? It seems easy enough to route the lines from the new master straight to it and hang it below as you did. And keeping it doesn't limit the benefit of the swap, right?

[cdl723]

Well I ended up ordering a clevis from McMaster-Carr that was 20mm longer than the stock e30 clevis and cutting m10x1.5 threads into it. I also remade hard lines from the ABS unit and looped them around to fit. The part number is for the clevis 2448K51. I had to trim it a few mm to fit on the threads as there was not a ton of room to adjust it with a locking nut.

The brakes feel assisted, but firm all the way up until I get close to locking the brakes up. At about 80% of the pedal travel/deceleration the pedal gets really stiff and it takes almost double the force to get the last 20% to lock the brakes up. I am wondering if anyone else has experienced this or if the booster is bad?

[cdl723]

I just picked up an E90 booster and the pedal is probably ~1/2" from the light switch on my car. Would cutting the clevis off of the e90 booster, cutting threads and adding the e30 clevis have enough room to adjust the pedal up? I have an e28 clevis on order, but I think it will take some time to get here...

Also, are any good spots to put a proportioning valve on the rear line? The engine bay is quite crammed and I am unsure of where to put it to get good access, but not create a local high spot

[Chilezen]

I'm trying to use an e90 booster in my 87' that HAS ABS, and I seem to have only one line running into my master cylinder's setup

How do I properly connect my e90 booster if I do not want to remove my ABS......is it even possible?

It's a proportioning valve only on those models/that year. I have the same. Some people get rid of theirs. I went through the extra effort to bend the lines and relocate it to underneath the master, positioned horizontally. See my post above, you can baaarely see it hidden under there. I'll try to get a better photo soon.

[Buff_e30]

I'm trying to use an e90 booster in my 87' that HAS ABS, and I seem to have only one line running into my master cylinder's setup, its like connected to iteslf in 2 places (see pic)....

This is a stock pic i found on the internet but it clearly shows the current setup i have in my car, the 2 lines from the main master go to like a "secondary"? master and there is only one line connected to it on my car where the green circle is

How do I properly connect my e90 booster if I do not want to remove my ABS......is it even possible?

[mjweimer]

Same:

Use (2) of the 2002 fittings off of the top of the master cylinder - 34 32 1 102 282

Along with a meter of the cloth covered rubber hose - 21 52 1 163 714


Agree that it is not fun fishing the hose for the clutch master through the firewall grommet but in the whole scope of the swap it's not too bad. If you still have your original line going through the firewall, tape the new hose to it to help guide it through.

[Chilezen]

For anybody that used a remote 2002 res on the e83 master, what lines did you use to run the extra distance from master to remote res? Finishing up my install now

I bought a meter of new clutch line. I replaced the old clutch line (I had to, the original was too short to reach the new res anyway), and then used the rest for the brakes.

Replacing the clutch line (where it goes through the firewall to the clutch master) was one of the worst, most irritating jobs I had to do within the whole swap. Getting that hose on the fitting was such a pain. Good luck if you do. Appearance-wise, worth it to have all new lines, versus using a coupler to extend the old one.

[TheGreatDecay]

For anybody that used a remote 2002 res on the e83 master, what lines did you use to run the extra distance from master to remote res? Finishing up my install now

[nwn54]

Speaking as a welder, I went that route.. cutting it shorter and welding the E30 clevis on the rod. The biggest issue is putting too much heat into the rod, which may melt the plastic inside the booster (and it doesn't matter if you're welding a bolt or the clevis on).

I think the way others do it, who don't have a welder, just use an angle grinder with a flap disc, and slowly shave the rod thinner, going around and around the rod, taking off material a little at a time. It's effective but I didn't see enough material there for me to shave enough, and then use vice grips to hold the rod as threads are cut.

The fact that you spoke with experienced machinists means you spoke with guys who have already done enough shit to know what is right and what just works well enough. Most of us here are in the second boat, just doing what we can to get our cars on the road.

If I'd do it again, I'd weld a bolt on the rod. Mainly because I have the ability to do so.

Thanks for the comments. Both machinists said with the rod removed from the booster it would take more time to set up the die, than to cut it. Removing it doesn’t seem to be an option. The slowly shaving it thinner and cutting the threads option seems very tedious, and hard to get accurate. I think we are going the TIG weld direction. I have access to two great welders.

[Chilezen]

Speaking as a welder, I went that route.. cutting it shorter and welding the E30 clevis on the rod. The biggest issue is putting too much heat into the rod, which may melt the plastic inside the booster (and it doesn't matter if you're welding a bolt or the clevis on).

I think the way others do it, who don't have a welder, just use an angle grinder with a flap disc, and slowly shave the rod thinner, going around and around the rod, taking off material a little at a time. It's effective but I didn't see enough material there for me to shave enough, and then use vice grips to hold the rod as threads are cut.

The fact that you spoke with experienced machinists means you spoke with guys who have already done enough shit to know what is right and what just works well enough. Most of us here are in the second boat, just doing what we can to get our cars on the road.

If I'd do it again, I'd weld a bolt on the rod. Mainly because I have the ability to do so.

[nwn54]

...unless You mount them upside down ;)

As to the problem with clevis pin - here's what I did (inspired by Pazi88 solution shown in his video, thanks!):
1) first, I cut off the forkhead;
2) then, I shaved off the rod a little bit and tapped it with m10 x (probably) 1.5 thread;
the rod is quite too short to grab the thread with original e30 forkhead, so...
3) I bought a genuine BMW e28 535i forkhead (p/n 34331150988, price in the USA ~6$ at Turner Motorsport) and used it instead of e30 forkhead.
E28 fork is a bit longer, fits perfectly and still we can have an adjustable fork, just as before. And original e30 clevis pin can be used.

I forgot to take pictures, so here is (partly) illustrative photo:

Any more details on how to thread the end of the booster rod? I have talked to two very experienced machinists and they think the rod must be removed from the booster to machine it down from ~12mm to M10x1.50. They both suggested cutting the rod shorter and TIG welding a bolt on the rod… Any help on the actual process of machining the threads on the e90 booster rod would be very appreciated. Thanks.

[twright]

In my experience, having a Euro Vin helps. I don't always have one available for the part I'm buying (especially E46) and if the part is not mapped for sale in the US and you don't have a vin it requires a request to map the part for US sale. No doubt,...parts from Germany take forever to arrive these days.

Yes, you're right. They would only order a Euro part for me if I showed them the title or registration for the vehicle.

[mjweimer]

I haven't had any problem at Dreyer and Reinbold in Indianapolis ordering Euro parts. It just takes forever for them to come in.

In my experience, having a Euro Vin helps. I don't always have one available for the part I'm buying (especially E46) and if the part is not mapped for sale in the US and you don't have a vin it requires a request to map the part for US sale. No doubt,...parts from Germany take forever to arrive these days.