Best Brake Booster For M52B28 E30 Conversion?

[darrencnz 10]

Hey Guys

So i am putting the M52B28 into my E30 and i have read numerous forums and articles (some local, some overseas) and the general consesus seems to be to use one of the following....

E21 Brake booster

VW Golf Mk2

Porsche 944

Renault Clio

I would love some feedback from people who have done this and preferably in NZ as im sure some of these are easy to find in european countries but not so easy in NZ.

I also understand that this mod NEEDS to be done with this conversion so there must be a wealth of information out there. I'm not necessarily looking for the cheapest solution, i'm more looking for the best solution and it's something i want to do correct from the start.

I was leaning towards the E21 because, i figured it would be the easiest to sort, is BMW, from a similar model etc, etc but after trying to find one, am struggling due to it's age and cant seem to find a new replacement.

Please let me know what you guys think and what to stay away from, i'm only a few more parts away from being able to actually get started on this conversion.

Darren

[slybma 38]

When I did my conversion I tried the e21 booster because of clearance and it worked well but I did notice the brake feel wasn't as good, it just wasn't boosting as much, so I swapped the original back in and just moved it over and the brakes feel much better. That's just my opinion though as the car has been build for a lot of track use so I wanted good brakes

[polley 916]

Ive used e32 vacuum booster and master cylinder on 4 swaps now. Last two I slotted the holes in firewall to move it down and across for extra clearance

[darrencnz 10]

Slybma - Are you saying the standard E30 will fit ok?? The diameter of it is huge but it is quite flat, i wasn't aware from the reading i have done that it was even an option.

Polley - so with the E32 setup, is the clearance issues only quite minimal? i cant imagine you would be able to move the location too much due the mechanism inside the car.

I haven't had a real good look to see how much room i have and i've just taken a look online at some of the boosters and they look much smaller than mine. I have a 1990 model and my booster looks much bigger than some i have seen online.

I'll prob get the master cylinder re-sleeved for piece of mind but do i need to check anything for wear on the booster itself?

Thanks for the replies

[slybma 38]

Slybma - Are you saying the standard E30 will fit ok?? The diameter of it is huge but it is quite flat, i wasn't aware from the reading i have done that it was even an option

Ya I'm using the original e30 booster, I moved it down and left 15mm and removed the intake manifold fins, in hindsight I'd have gone with the e32 setup

[darrencnz 10]

Hmmm... Things is my brakes are a bit funny at the mo and im really not sure what it is either.....

I've replaced all the pads, discs etc recently on all 4 corners even though i knew that wasn't the issue as i can hear something coming from the current booster that kinda sounds like hissing (air) so am thinking that the timing was good to just do a proper upgrade while im fitting the new motor anyway.

I've been making some phone calls today and talking to a few people and it looks like the Mk2 Golf booster/MC combo is the one im starting to lean towards if i can find one but i'm totally open to other peoples suggestions.

Because the booster is quite small and bolts staright up without needing to mod any of the location holes apparantley but would love to confirm this. Dont mind dremelling a couple of fins off if that solution doesnt work out but this guys has it in his E30 race car and said it's brilliant.

[_ethrty-Andy_ 2136]

have replied to your PM

[polley 916]

Hmmm... Things is my brakes are a bit funny at the mo and im really not sure what it is either.....

I've replaced all the pads, discs etc recently on all 4 corners even though i knew that wasn't the issue as i can hear something coming from the current booster that kinda sounds like hissing (air) so am thinking that the timing was good to just do a proper upgrade while im fitting the new motor anyway.

I've been making some phone calls today and talking to a few people and it looks like the Mk2 Golf booster/MC combo is the one im starting to lean towards if i can find one but i'm totally open to other peoples suggestions.

Because the booster is quite small and bolts staright up without needing to mod any of the location holes apparantley but would love to confirm this. Dont mind dremelling a couple of fins off if that solution doesnt work out but this guys has it in his E30 race car and said it's brilliant.

e32 one is great as its double diaphragm, so even though it is smaller diameter is still has a sh*t load of assist. smaller single diaphragm setups make a sacrifice there, they are smaller but offer less assist. i kept the e32 master cylinder, which is larger at 25mm, pedal dosent move much and requires more force than the standard setup.

actually, through the different stages of the car ive probably f**ked with the brakes more than i recall and its not actually a straight forward swap anymore to reproduce what ive done with out a lot of mucking around.

[darrencnz 10]

Thanks for all the info guys.

[Jonty m50e30 0]

Golf mark II bolts straight up with the m50 conversion, works well.

[antil33t 90]

I just bought a 944 booster, was looking into E32 - but someone put one up for saleh here, so jumped on it.

[darrencnz 10]

So i've got the car back, new discs front and rear, new pads front and rear, new shoes in the rear, resleeved master cylinder and vacuum bleed and a Golf VW booster...

Still feels horrible and spongy but it does stop the car, i just hate a spongy pedal, any suggestions?

[polley 916]

lol....

[FIAT 131R 223]

I used the VW Golf booster in my M54 swap into the E30 and also put in a larger master cylinder . The master cylinder is a BMW H1 25.4mm non stepped one. I have some new ones if anyone is interested.

My E30 stops really well.

Edited December 1, 2014 by FIAT 131R

[will 169]

Two things to check:

1. What wear/flex do you have in the overall linkage from the pedal across to the booster? If each joint has a small amount of play, it all adds up. Also, if the pivot arms on either end of the log rod flex, that will add to the spongy feel. Some later models had a brace on the pivot behind the glove box for that reason. Also, make sure the push rod into the master cylinder is properly adjusted.

2. Are the floating callipers moving freely on the guides? If they are sticky or out of true, they will cause the pads to sit a little further away from the disc, resulting in a long pedal. Take the callipers off and lube the guides and check that the guides are perpendicular to the disc.

[darrencnz 10]

Yeah i managed to get a bit of pedal back from adjusting the rod, maybe im expecting too much, my thought was also the linkage issue, id love to test drive a LHD to see the difference.

I just really like a firm pedal and after replacing the entire brake system, i thought it would be better than what it is, the brakes are there but not as good as id like them to be.

[skidz 197]

So I bought a VW Golf booster, from 1 1993 model, but it does not appear to be a straight bolt up job - the push rod on the E30 booster sits flush with the front of the booster, but the Golf one is recessed about 20mm Also the Actuation rod at the rear is quite different - Have I got the wrong one?

[Silver Fox 43]

I used the E32 double chamber one on our M54B30 race car conversion, standard fitment, excellent brakes. Plenty of stop, 10mm clearance, would recommend it to anyone. We also run with the Mazda front calipers.

[e30ftw 410]

You may have the wrong one Stephen. Yes the push rod is shorter, you fit a spacer into the master cylinder. Just make sure it's the correct length. I have used Mk2 Golf ones always, not sure what year. Exactly the same as e30 though.

[Ahmedsinc 414]

So I bought a VW Golf booster, from 1 1993 model, but it does not appear to be a straight bolt up job - the push rod on the E30 booster sits flush with the front of the booster, but the Golf one is recessed about 20mm Also the Actuation rod at the rear is quite different - Have I got the wrong one?

If you got one from a '93 you'll have bought a MKIII by mistake. MKII was discontinued in '92, production started in '83. Anecdotally I have heard of better results from the E32 booster than the Golf unit (As David points out above), but having never driven them back to back I can't offer any direct observations sorry

[skidz 197]

thanks, guys.

[darrencnz 10]

I used the E32 double chamber one on our M54B30 race car conversion, standard fitment, excellent brakes. Plenty of stop, 10mm clearance, would recommend it to anyone. We also run with the Mazda front calipers.

I'm about to do the mazda rx7 brake conversion, how do you find it?

I'm running the Mk2 booster too, i dont have any experience with anything else but seems to work fine. I had trouble bleeding the rears and the guys at the brake shop said that the rod into the master cylinder might be too long so i shortened it and made it too short. i've now maxed out my adjuster to get a decent pedal but its still not where id like it so and just going to wait till i do the rx7 brakes and sort the new rod out and the adjuster to get it exactly how i want it.

I found an old pushrod works well for the extender rod as it self centres at one end and if it can handle the forces in an engine, it can handle my foot on the brake.