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I hope the comment from David Siddall below helps.
GOO did the same on the prototype. A longer high tensile M6 would achieve the same more easily. Better still if you then add extra spacer/lock nuts to create a stiffer section over the exposed threaded length.
Mike
Mike wrote:
Hi All
David Siddall collected one of the two sample servos on Saturday, and has just sent me the following comments:
[Hi Mike. Just a note to say that I've installed the servo and although I've only been up and down the drive, first impressions are very favourable. The brake pedal has more bite which is what I wanted.
The adjustment on the servo pushrod is not quite long enough with the m/c that I have, so I turned a suitable radius on a 25 mm length of 10mm diameter rod and put m6 thread into it which screws into the end of the servo pushrod.* This brought the end of the pushrod just flush with m/c face of the adaptor plate which is where the metro pushrod was.
I'm happy with the adaptor plate that you've already sent**: studs welded in and a coat of hammerite and it looks fine.
I hope you are as pleased when you get to fit yours...................thanks once again. Regards David. ]
* GOO has prepared exactly the same for his Sportster as par6t of his evening classes ( - and very kindly one for me too.)
** I gave David one of the first prototype adaptor plates designed for the Duksville servo, so the vacuum elbow was slightly out of place.
I have asked David to give us a more extensive report when he has had the chance to go out on the road and test it more fully.
But re-inforces GOO's comments...............................
this was my background thought. Taking 10mm off the end would be straight forward and low risk but I think that 25mm will see the push rod go well past the outer edge of the M/C. If we could get some extra adapters made up you could layer up another 2 and then it's just a 15mm cut. it will start to look a bit rubbish though.
The only problem I can see with moving over to a Ford M/C (apart from the fact we're not sure which one to go for) is that although new cylinders are available on ebay, I've not found a single reservior. This is fine for those with remotes but no good if you want to go the traditional route. I think if we can nail down the correct Ford M/C then as you say, it's more than worth the extra £40 to do the job properly.
Mike wrote:
Guys
Please be careful.
The brake master cylinder has to be one of the most significant safety critical items on any car. Embarking on a procedure to cut and carve must be undertaken with great care.
Suitable new master cylinders are available for £30-40: is it really worth the effort, and risk?
Mike
Reservoirs are available in scrapyards on old Sierras, and more modern Fords. I'm told Sierras are scarce down South, but readily available in t' North.
Mike
morris wrote:
The only problem I can see with moving over to a Ford M/C (apart from the fact we're not sure which one to go for) is that although new cylinders are available on ebay, I've not found a single reservior. This is fine for those with remotes but no good if you want to go the traditional route. I think if we can nail down the correct Ford M/C then as you say, it's more than worth the extra £40 to do the job properly.
Simon Gregory fitted one from an XR4i and said it is good. Peter Morris fitted one from a 1.8 LX Sierra one and said it was good too! The smaller the diameter, the better the brake pressure will be: the down side being more pedal travel for the same effect.
The situation with the Ford master cylinder is even worse than you imply. There are also two very different flange sizes and hole centres! I beleive the better one to get is Lucas Girling, and not the Bendix one. The adaptor plate has been supplied with an etched 70mm pcd for the smaller flanged BMC, with holes at 70mm centres (Lucas Girling? - please check first though).
I have seen ones like I chose advertised for Transit Vans. John Tootle (Cabrioman) was going to investigate this - don't know how far he got.
As Mike has said I decided to swap my Hunter M/Cyl with remote reservoir back to a standard Sierra M/Cyl with the reservoir mounted on the cylinder as per Mikes. Fortunatly I had one in the garage as a spare from my original Cabrio donor Sierra, a 1992 Sierra 2.0 LX. The only marks on the cylinder are a stamp stating "22" which I understand is the bore size in mm. This is the same cylinder Pete Morris had fitted to his car, again taken from a standard Sierra.
I would think an enquiry at a local motor factors would turn up the correct cylinder (I am prety certain mine is a girling), the difficuly maybe the reservoir. That said although I have not tried it the cylinder I have with the directly mounted reservoir looks like it would take the pipe outlets Marlin used for the remote setup, so that may be a possibility.
Perhaps someone has an old BMW master cylinder that can be stripped to see what's what?
I'm stripping a 1994 E36 at the moment and I've got no need for the master cylinder - I'm happy to take it to pieces and take measurements/photos if it'll help someone...
I found some better pictures of the E30 M/C. It looks that it cannot be used as there is a seal in the bit that protrudes forward of the mounting flange. Shortening the push rod 25mm would almost certainly compromise this as the push rod would disapear past the seal if there was any more than a few mm movement.
Is there a good picture of the M/C used by Jason anywhere that shows this detail for the ?Ford? M/C. Just for comparison....
Robin, then it's as I feared the E30 can't even be fiddled with. Can you point us to the photos you were referring to that show the seal?
Mashtun, thanks for the offer but I think you'll find your E36 M/C is even worse than the E30 one in this instance
The shank that protrudes past the fixing base points is even longer and slightly bigger diameter. I did get mine out of the "to be ebay'ed" box last night for a look but immediately threw it back in when I remembered the reason I had to buy the E30 one in the first place.
So, it's looking like an as yet unidentified ford part or a set of stand off spacers which are almost guaranteed to raise eyebrows at IVA time. I'm going to get the servo mounted up on the pedal box first so then I have an idea of how much there is to play with before the M/C hits the side of the engine compartment
Does this help? It is a Ford m/c marked "22" - it has markings on it 311809, and Q29
The projection of the Ford m/c beyond its flange face is around 23mm, much the same as the depth of the dual servo recess. The adaptor thickness of 6mm giving sufficient clearance.
Mike
MartinClan wrote:
I found some better pictures of the E30 M/C. It looks that it cannot be used as there is a seal in the bit that protrudes forward of the mounting flange. Shortening the push rod 25mm would almost certainly compromise this as the push rod would disapear past the seal if there was any more than a few mm movement.
Is there a good picture of the M/C used by Jason anywhere that shows this detail for the ?Ford? M/C. Just for comparison....
In the Cabrio it gets closer to the underside of the bonnet than the side, so be sure to check for height clearance. Of course you may have more room in the Sporster, and it may not be such an issue.
The Ford m/c I have seems quite long. Not sure about Jason's m/c though, although we know it fitted under the bonnet ok.
Mike
morris wrote:
I'm going to get the servo mounted up on the pedal box first so then I have an idea of how much there is to play with before the M/C hits the side of the engine compartment
Robin, then it's as I feared the E30 can't even be fiddled with. Can you point us to the photos you were referring to that show the seal?
They were just some images on google that I found....
I looked at Jason's web site. I am unable to use the master cylinder similar to he used as it has THREE outputs. The E30 one has two outputs and all my plumbing is likewise. Hmm nothing is ever as simple as it seems. But then it wouldn't be so much fun :-)
Robin, my E30 M/C has 3 outlets as I removed the screw in cap on the bottom though I don't know that this helps you.
Unfortunately I don't have any bodywork yet so all I can do is eyeball it. I've fettled the pedal box now with a round file and trial fitted the servo so at least I've got a reference point to work from. Maybe a tiny power bulge in the bonnet (for the brake reservoir) will be the solution
I've just checked and my E30 M/C cost the princely sum of £12 so despite spending time cleaning it up and making it look all silver and pretty, it qualifies a potential guinea pig for the angle grinder
Hi Mike.
Thanks, I will probably go this route as it seems stronger than extending the push rod screw out too far. Many thanks also for the tip about the G-Cramp.
I ordered some 8mm Hi Tensile Steel countersink screws from Namrick in Hove and they arrived next post so can recommend them as a supplier if anyone else needs them for hooking up the adaptor to the master cylinder. Tel 01273779864 or [url]www.namrick.co.uk[/url]
Peter.
Mike wrote:
V8 Peter
I hope the comment from David Siddall below helps.
GOO did the same on the prototype. A longer high tensile M6 would achieve the same more easily. Better still if you then add extra spacer/lock nuts to create a stiffer section over the exposed threaded length.
This looks very dodgy but is actually pretty strong. With some reinforcement on the front face of the servo and standoff sleeves at 4 x opposite points it could work nicely. The stand off gains 15mm so the M/C would only need 10mm trimming from the end of the plunger. I'll be spinning the Servo 90 degrees anticlockwise so I can mount the M/S the right way up and keep my reservoir
This all of course depends 100% on the assertion that the M/C and servo don't need an air tight seal because in this case, I think I'd struggle to make one
As far as I can tell this also will not cause the M/C to foul either the side panels or the bonnet (thought the latter is guess work). If one of the other builders can mock up the same thing and make a few measurements this may be some way to the solution
From memory I am using a ford m.c. -think it is this as it is mounted at an angle with remote reservoir on metro servo. looking at it in-situ it has the number 383059 on it
My m/c is for the Ford Sierra and has the same no. on it: and has the Sierra reservoir mounted directly on top.
Mike
jeremy wrote:
From memory I am using a ford m.c. -think it is this as it is mounted at an angle with remote reservoir on metro servo. looking at it in-situ it has the number 383059 on it
Looking at my old (E30 OE) m/c I find that the full travel of the shaft is 13mm and it would therefore be possible to cut 15mm off this shaft without effect on the seal. However, the circlip is tamper-proof so I have not been able to look inside.
On my new (after market) m/c, on the other hand, the shaft can be pushed in its full length. Similarly, the dual servo shaft certainly travels more than 13mm. The servo output shaft would also need to be considerably extended if the BMW m/c was used.
It would seem possible to bodge the two together but in my view it would look horrible and would be mechanically very suspect. Personally, I do not think it deserves further consideration.
The BMW cylinder seems to be 25mm inside diameter measured at the circlip. I wonder how critical this diameter is for pedal feel?
It occurs to me that, although the Ford m/c is the obvious answer, there must be an m/c out there that has the same stud pattern as the servo and would fit without any spacing? I will have to keep looking!
Changing the subject slightly, has anyone looked closely at the pictures of the new factory built M3 Sportster in Complete Kit Car Magazine. There is no sign of a servo or m/c in the normal place so I assume Mark has gone for a remote set up. I think the servo may be in the battery tray. Also, the exhaust is interesting with silencers down each side and rear tail pipes. I look forward to a close examination.
yep, Mark put the standard BMW servo in the battery tray with a linkage through from the pedal box. I remember asking him when I saw it about a year ago if that was the way to set things up now and and he said it was so complicated to to get right that he'd not do it in future
Yes ,you are right Ian. When I was at the Exeter show Mark said the same then. That car is a one off as far as the servo is concerned, so don,t go down that route.
Ian, your cunning plan looks interesting but I would prefer the M/C to be fitted flush onto the plate, with all its mounting surface in contact with the back plate. There is a lot pressure there and I would always wonder if the fixing would move. Having said that I am not a mechanical engineer.
Be interesting to hear other peoples opinion on your solution
yep, I quite agree that I'd prefer it flush too. If there wasn't this question mark over what the right part number is for the ford cylinder I'd just be ordering one of those and washing my hands of the BMW part but I don't want to waste money through trial and error finding the right part.
With the setup shown in the photo I wouldn't be happy but with a good brace at 4 points rather than 2 I think it would be solid. It's worth remembering that the forces involved in pushing the M/C are nothing in comparison to the tensile strength of a bog standard bolt so as long as everything is straight and you're not pushing the M/C at an angle, it will be mechanically sound. If I take 10mm off the plunger then the M/C will sit flush to the 5mm thick adapter meaning the forces will be spread nice and even
The question in my mind is all about the air tight seal as if that is an issue then it's a non-starter.
Please do not take this as suppotrting your idea to cut and carve your BMW MC, but there is not an issue with maintaining the seal. The MBM servo is self sealed. We know this from GOOs trial with my first adaptor plate which had a slight bow in it.
I have a pattern MC for a Ford and will try to find out on Monday where I sourced it from and if they are freely available.
Mike
morris wrote:
yep, I quite agree that I'd prefer it flush too. If there wasn't this question mark over what the right part number is for the ford cylinder I'd just be ordering one of those and washing my hands of the BMW part but I don't want to waste money through trial and error finding the right part.
With the setup shown in the photo I wouldn't be happy but with a good brace at 4 points rather than 2 I think it would be solid. It's worth remembering that the forces involved in pushing the M/C are nothing in comparison to the tensile strength of a bog standard bolt so as long as everything is straight and you're not pushing the M/C at an angle, it will be mechanically sound. If I take 10mm off the plunger then the M/C will sit flush to the 5mm thick adapter meaning the forces will be spread nice and even
The question in my mind is all about the air tight seal as if that is an issue then it's a non-starter.
All
I have just had a call from Alan Hogg to say he has fitted his servo kit in his Cabrio (BMW M20) today, and is thrilled with transformation of his brakes. "A revalation" to use his own words. He has his car on the road all year around, and has taken it for a proper drive, and says the pedal has much more feel to it, and that if he wanted to, felt he could have locked his wheels up. A real success.
I am delighted with his call on many levels. Obviously with 20 people buying the kit I felt a real sense of responsibility for ensuring you were not disappointed! So to have someone be so pleased that he wanted to give me a call to say thank you personally is very satisfying. He found the kit very easy to fit, and was pleased with its quality and simplicity. He drilled two holes, added a counter sink at the rear, and fitted it.
I am also pleased because Alan's Cabrio is Ford based and he has the same Cosworth disc front & rear disc set up with a Ford MC that I have selected. So all being well my brakes should work.
I tghink the moral of the story is that with a Ford master cylinder the conversion is simple straight forward, and it works.
I do hope all of you with BMW master cylinders are able to find a safe workable solution and that it works just as well for you. Jason, GOO, has PM'd me that he is fitting his servo today, so hopefully he will be able to elaborate a little more on the success of the kit in a BMW based Sportster.
