M50 conversion - brake servo question

Post Wed Apr 19, 2006 9:25 am

Looked at the M50 developments thread, as I understand it it seems the Porker 944 brake servo + standard E30 master cylinder is the best option?

Better than the Mk 2 Golf servo option?

Will the mk 1 golf servo work?

Which year 944 or does it not make any difference?

Is the 924 servo the same as the 944 servo? Part numbers anyone?

Your help is much appreciated.

Post Wed Apr 19, 2006 9:33 am

Also: How do you say "brake servo" in German?

Alta vista translation of "bremse servo" does not seem to throw up any hits on Ebay.de

Post Wed Apr 19, 2006 12:49 pm

Why do u want to remove stock brake servo ? Nobody do this, because it fits perfectly with right rubber mount and spacers. I used M20 motor rubber mount on the exhaust side + 6mm spacers. On the intake side e34 rubber mount and ~20mm spacers. Also you can use e30 M3 rubber mounting on the intake side + 10mm spacer, but e34 mounts are cheaper.. And it is recommended to remove few plastic 'teeth' from intake manifold near the brake servo.

Post Wed Apr 19, 2006 9:16 pm

Hi Alex

The Porsche servo is one option, but I dont know if its the best, or any better than the Golf/BMW servo - I think they are all ATE servos. I dont know what mods are needed to fit the Poker servo or how easy they are to find.

From the Mk2 Golf, its the 1.3 servo you need - the Gti servo is too big. The 1.3 servo will fit, but needs the spacer as written in the 'M50' thread.

From the Mk1 Golf, its the GTi servo you need (I have this on my S50 conversion) and it fits slightly better than the Mk2 1.3 servo without the need for the spacer. The Mk1 1.3 servo is too small.

I think I understand what Laimis has done to fit the E30 servo, but I have no idea how this affects the engine position. My guess is that the engine is rotated slightly away from the servo, but this will also rotate the gearbox, which means the gearbox mounting will also need spacing out and the gear shift will be off line slightly.
That is a complete guess, so if Im wrong then Im happy to be corrected.

Post Wed Apr 19, 2006 9:51 pm

It will also give you even less room for routing a manifold around the steering joint and increased movement from the M20 mount.
I first mounted mine on M20 arms with several combinations of rubber mounts and spacers but it would of caused too much hassle trying to mount the gearbox and getting the selector in the right possition, and the bottom of the sump was no-where near horizontal.

Post Wed Apr 19, 2006 10:10 pm

I mounted mine right the very first time, E36 alloy mounts with E34 525i rubber mounts!

But I did do a lot of reading up on here first! I changed my servo even before trying to put in my engine!

Post Thu Apr 20, 2006 3:28 am

BTW some trawling through Ebay, I understand that the Brake servo from the E30 325iX will do the job and is the solution used in Germany for E30s with M50/S50 engine conversions. From the pics, the iX serco is of a smaller diameter but there seems to be 2 servos piggy backed one behind the other.

So, anyone here tried the iX servo?

Post Thu Apr 20, 2006 3:31 am

jmc330i wrote:Hi Alex

The Porsche servo is one option, but I dont know if its the best, or any better than the Golf/BMW servo - I think they are all ATE servos. I dont know what mods are needed to fit the Poker servo or how easy they are to find.

From the Mk2 Golf, its the 1.3 servo you need - the Gti servo is too big. The 1.3 servo will fit, but needs the spacer as written in the 'M50' thread.

From the Mk1 Golf, its the GTi servo you need (I have this on my S50 conversion) and it fits slightly better than the Mk2 1.3 servo without the need for the spacer. The Mk1 1.3 servo is too small.

I think I understand what Laimis has done to fit the E30 servo, but I have no idea how this affects the engine position. My guess is that the engine is rotated slightly away from the servo, but this will also rotate the gearbox, which means the gearbox mounting will also need spacing out and the gear shift will be off line slightly.
That is a complete guess, so if Im wrong then Im happy to be corrected.

jmc330i

Thanks for clearing that up. Will try to look for a Golf 1 GTi servo or perhaps an iX item if someone can confirm that they will deffo work!

Cheers

Post Thu Apr 20, 2006 3:53 am

jmc330i wrote: I think I understand what Laimis has done to fit the E30 servo, but I have no idea how this affects the engine position. My guess is that the engine is rotated slightly away from the servo, but this will also rotate the gearbox, which means the gearbox mounting will also need spacing out and the gear shift will be off line slightly.
That is a complete guess, so if Im wrong then Im happy to be corrected.

Yes, the engine is rotated a little, but sump position is almost horizontal. Also shifter position is OK either. Gearbox mounts we manufactured new, because 525iX gear box does not have any. Anyway, tomorrow i hope swap will be done, only exhaust is left. I just came home from the garage and it is 5 am already

Some pics from today progress:
http://cs.ku.lt/~inf033/laimis/images/e ... path=day8/

Post Thu Apr 20, 2006 4:59 am

jmc330i

Just to confirm that the Golf 1 GTi mates to the normal E30 brake master cylinder? Is that what you are running on? Are you happy with the brakes you have on now? Are you combining it with some trick pads and discs?

Cheers!

Post Thu Apr 20, 2006 9:31 am

Thought the latest " best " solution was Golf Mk 1 servo with Audi m/cylinder.
Laimis - Is your car LH or RH drive?
The E30 iX servo is a small diameter tandem servo, as is, IIRC, one from a current 7 series.

Post Thu Apr 20, 2006 10:28 am

Brianmoooore wrote:Thought the latest " best " solution was Golf Mk 1 servo with Audi m/cylinder.

I think the Audi M/C is used with the Mk2 Golf servo because it fits directly, without the spacer between the M/C and servo. The push rod of the Audi M/C may be too long for the Mk1 Golf servo.

The Audi M/C is also shorter than the E30 one, so this help with clearance around the intake boot on the S50 conversion - Im not sure if the extra clearance is needed on the M50 conversion.

alexbaby88 wrote:jmc330i

Just to confirm that the Golf 1 GTi mates to the normal E30 brake master cylinder? Is that what you are running on? Are you happy with the brakes you have on now? Are you combining it with some trick pads and discs?

Yes, the E30 M/C is a direct fit to the Mk1 golf servo.
Ive only driven the car a few yards so cant really say how good the servo works, but it doesnt feel any different to the E30 servo (from what I remember) at slow speeds. I do have uprated pads and discs, but I wasnt going fast enough to notice them - Hopefully, I will soon be running full E30 M3 brakes with the Mk1 Golf servo and Im not foreseeing any problems with that.

Althought the servo is smaller in diameter, it is thicker (from back to front) so the way I see it, is that its about the same volume as the E30 servo if that makes sense?? This pic will help explain what Im saying....

Post Thu Apr 20, 2006 12:01 pm

jmc330i

Thanks for the servo comparison pics!

Do you have any more info on the use of the 325iX servo?

Looking for a more servo power than the standard E30 servo for better bite.

Thanks

Post Thu Apr 20, 2006 12:03 pm

If your looking for more servo power then go for the Mk2 Golf servo, its half the size so it has double the power!

Post Thu Apr 20, 2006 2:04 pm

alexbaby88 wrote:jmc330i

Thanks for the servo comparison pics!

Do you have any more info on the use of the 325iX servo?

Looking for a more servo power than the standard E30 servo for better bite.

Thanks

??????? E30s are over servoed already, if anything!

Post Thu Apr 20, 2006 2:08 pm

jmc330i wrote:[
Althought the servo is smaller in diameter, it is thicker (from back to front) so the way I see it, is that its about the same volume as the E30 servo if that makes sense?? This pic will help explain what Im saying....

Volume's got nothing to do with it - that's only the resevoir.
Assistance is directly proportional to the area of the diaphragm, whioch for practical purposes is proportional to the square of half the diameter of the unit.

Post Thu Apr 20, 2006 4:15 pm

Brianmoooore wrote:
alexbaby88 wrote:jmc330i

Thanks for the servo comparison pics!

Do you have any more info on the use of the 325iX servo?

Looking for a more servo power than the standard E30 servo for better bite.

Thanks
??????? E30s are over servoed already, if anything!

Am having some braking issues, even when I stand on my brakes at max, I can't even trigger ABS. The car just won't stop! I have fresh ate pads, black diamond discs and goodridge hoses.

I have tested the m/c using a technique suggested by Ian330isport (pump brakes with engine off till pedal goes hard, with brake pedal depressed turn on engine and the pedal should drop slightly as vacuum is re-established) and seems like my m/c is fine.

So perhaps its the servo?

Post Thu Apr 20, 2006 4:48 pm

Cheers Brian, I think I underdstand

Alex - Ive not seen a 325iX servo, but from the ETK the servo is the same ATE servo found in the normal E30 up to 1987. After 1987 it has the Girling servo thats also found in the E32 730i/735i and the E34 530i and M5.

Even with a knackered servo you still should be able to lock your brakes (trigger the ABS) although you will have to push the pedal much harder if the servo isnt giving enough assist.

Unless Im being totally dense (quite likely), how does the test that Ian suggested test the Master Cylinder - surely it would test the servo???

Post Thu Apr 20, 2006 5:31 pm

Even if I literally stand on my brake pedal, and I'm no skinny either

the ABS doesnt trigger and the lack of bite is simply shocking.

I'm just not sure what the problem is

I've emailed Tino at E30.de and he recommends the use of the iX servo for S50/M50 conversions.

Re the pedal test - you're absolutely right it tests the servo (I misread his post).

Still doesn't explain why my car don't stop though!

Post Thu Apr 20, 2006 6:12 pm

IMO I would get the brakes sorted before you do anything like an engine conversion.

You could have a problem with the m/cylinder or calipers, either way, I would want to get it sorted first - it doesnt sound good

Ive never really looked at the linkage that runs from the brake pedal across to the m/cylinder, but maybe its not acting on the m/cylinder enough? Im not sure if it can be adjusted, but worth a look??

Im not being funny here, but your car does have ABS right?
I had a friend of mine phone me up to say the ABS wasnt working on the car he had just bought and the wheels would just lock up and skid. I went to see the car and it didnt have ABS fitted

Post Thu Apr 20, 2006 6:24 pm

James will take up all your suggestions.

Yes I have an ABS light, although my brakes don't even come close to locking...

In fact I need to rebleed the braking system.

Cheers

Post Thu Apr 20, 2006 6:30 pm

alexbaby88 wrote: In fact I need to rebleed the braking system.

Should of suggested that too

Air in the brake system isnt going to help matters.

Have the brakes always been bad, or since fitting the goodridge hoses etc?

Post Thu Apr 20, 2006 6:51 pm

Laimis wrote: Anyway, tomorrow i hope swap will be done, only exhaust is left.

At least you havnt got a steering joint to go round

Post Thu Apr 20, 2006 8:55 pm

alexbaby88 wrote:James will take up all your suggestions.

Yes I have an ABS light, although my brakes don't even come close to locking...

In fact I need to rebleed the braking system.

Cheers

Air in the ABS unit can be VERY difficult to bleed out. I think the correct way is to use an electronic gizmo to pulse the ABS while you bleed the brakes.

Post Fri Apr 21, 2006 2:42 am

So the Mk2 Gti golf servo is a no-no for E30? beacuse I have one to pick up on saturday,tell me for sure so I dont buy the shit....

Post Fri Apr 21, 2006 3:04 am

you should be able to lock e30 brakes without servo assistance so i reckon there is an issue elsewhere..

Post Fri Apr 21, 2006 3:19 am

Eddy wrote:So the Mk2 Gti golf servo is a no-no for E30? beacuse I have one to pick up on saturday,tell me for sure so I dont buy the shit....

Its the same size as the E30 one I believe! You need the MK1 GTI servo or the non GTI MK2 servo!

Post Fri Apr 21, 2006 10:26 am

Jhonno wrote:you should be able to lock e30 brakes without servo assistance so i reckon there is an issue elsewhere..

Thanks guys,gona tell the seller that I dont need it

Post Fri Apr 21, 2006 7:09 pm

stevetigger wrote:
Eddy wrote:So the Mk2 Gti golf servo is a no-no for E30? beacuse I have one to pick up on saturday,tell me for sure so I dont buy the shit....

Its the same size as the E30 one I believe! You need the MK1 GTI servo or the non GTI MK2 servo!

Thats correct.

Post Sat Apr 22, 2006 1:57 pm

HELP I think my Audi M/C is no good! It has four instead of the two inlets for the brake pipes, could I just plug up the other two?

Post Sat Apr 22, 2006 2:34 pm

Post your pic here, Steve.
Just looks like two drillings into each chamber, like I said. You should be able to blow through from one side to the other.

Post Sat Apr 22, 2006 2:37 pm

They taste like oil but yes, it blows through to the other side! So just hook my brake pipes up and block the two on the wrong side!

Has anyone told you Brian, that you are a legend.

Post Sat Apr 22, 2006 2:37 pm

Brianmoooore wrote:Post your pic here, Steve.
.

Oops, see you already have!

Post Sat Apr 22, 2006 2:43 pm

All the E30 m/cs I've seen use three connections. Two for the front, and one for the back.

Post Sat Apr 22, 2006 2:45 pm

Im sure mine is just two! Hang on, I will just check!