Delco-Moraine ABS Deletion

[G_Reaper]

When I ditched the delco system a number of years ago on my S4s I looked at the V8 system and was shocked to find most of the V8 brake hydraulic parts no longer available including and essentially the vacuum supply pump. It was easier to get the SE set up as the T2 Transporter has most parts remanufactured as it is a classic in its own right.

For info on the merit of the MR2 /Subaru/ SE set up against each other as a retro fit see the old thread "calling all brake gurus"  For info on a company that supply a ready made solution to the vacuum supply issue see my thread about replacing the Delco system just got easier.

Making a fail safe system of supplying  vacuum and the correct amount of vacuum was the hardest part of replacing the Delco system. Now a company supplies a kit complete however it can be bought at a fraction of the cost as individual components. This kit was not available when I was ditching the Delco set up. 

Cheers Mike

[rizla603104]

Hi Mike, thanks for the information and I have read through the thread. Do you have the part numbers for the cylinder and servo? Also there was talk about the reservoir too. Finally, the mounting bracket and connection to the pedal what was used and what was involved - as I said I am mechanically illiterate - so baby steps appreciated for me.

[davevr6car]

I agree with Mike, in regards to the correct amount of vacuum been supplied.  When I did my conversion first on my S4s I used the Mr2 servo connected to an original SE vacuum pump. It made shite of the servo....too much vacuum. On my 2nd attempt I used a nissan patrol servo unit with a manual turbo bleed valve and an inline vacuum gauge.....this let me adjust the amount of vacuum going to the servo.....in other words I could adjust the amount of servo assist going to the brakes. The other thing to remember is to have a vacuum reservoir... if you loose engine power you'll have no vacuum....the same with an electric vacuum pump....if you loose electrical power, you'll have no vacuum......so I fitted an Audi A6 vacuum reservoir. Its not the hardest job to do to an Esprit.....but it's a completely different car once converted......you'll never look back........probably the best upgrade you can do to an Esprit!

[Chillidoggy]

I did search for T2 Transporter servos. The ones I found seemed to have some kind of weird attachment at the pedal end, but there could be others I haven't seen. And at over £300 for a new one, it's not the kind of thing I'd want to get wrong.

Without part numbers we're stuffed. Even a specific year would narrow it down, as (from my research) the VW T2 was produced over many years in all different variants. Then we'd need to know the master cylinder that fits the servo has the correct 15/16" bore. And so it goes on.

[G_Reaper]

That's not the same one? god knows what that is.

The master cylinder I bought new from PNM was a copy of the original Girling master cylinder used by Lotus however it was manufactured in Europe and the product code showed it to be for a VW transporter I will dig the part number and manufacturer out for you all. Once I realised the V8 parts were also obsolete I left that as a possibility and concentrated on the older system which was designed to work effectively without any ABS element to it.

Essentially the master cylinder was a standard Girling component also used on an earlier model VW transporter and possibly other vehicles, the servo was a standard servo unit also used on a Renault Extra van & possibly other vehicles. The reservoir on top of the master cylinder was a standard sloped unit to take into account the angle of the master cylinder the same as used on the Ford Transit of that era.  

I used a standard Esprit mounting bracket as used on the Stevens & G cars (I think) and the push rod off the same earlier Esprit. However it would not be hard to make a bracket and push rod.

You should be able to get more details about the servo off any Stevens Esprit owner. Servos can also be reconditioned. 

Martin L and I found no matter which setup you use the vacuum amount has a huge effect on brake feel.

It is essential to have a reliable constant vacuum supply. Hence I had a vacuum supplied by a Hella Vac pump supplemented by the engine when not on boost (did not throw up any engine management codes or lights) and  for further redundancy a huge Audi A6 vac reservoir mounted in the nose where the delco hydraulic pump used to be, so well hidden but also very close to the servo. All vac supplies were connected using silicone hoses with a vac non return valve (from a Vauxhall Vectra) close to the vacuum source. The adjustable Euro switch which switched the Hella pump on  was mounted close to the servo to give the most accurate vacuum measurement next to the servo where the vacuum is required. 

The vacuum pump was mounted in the rear compartment with heat shields as a precaution next to the other electric vac pump which supplies vac for the heater flaps. This was essential to keep the noise down as Martin L found mounting the vac pump in the nose even with rubber mounts it was incredibly noisey. The V8 and GT3 had their electric vac pumps mounted in the rear on top of the wheel arch I think. The V8 GT3 vac pump would have been ideal as it had the pre set vacuum switch built in however these were not available when I was removing the Delco set up from my S4s.

With the above set up the Hella vac pump has a very low workload as the constant vac supply from the engine to the huge A6 vac reservoir means the vac only needs topping up by the pump after much use of the brakes.

For further safety I also used an adjustable Euro Switch to switch on the brake warning light on the dash just in case for any reason there should be a lack of vacuum (A great help when adjusting the other Euro Switch to set the desired pedal feel)

I think I have a write up of this somewhere I can share with you.

Cheers Mike

Edited January 11, 2018 by G_Reaper2

[Chillidoggy]

The SE uses a Bendix servo and master cylinder, not Girling.

From my research (NB there may be overlap around the changeover points):-

The pre-1985 S3 cars used Girling servo and master cylinder.

The post 1985 - 1988 S3 cars used Bendix servo and master cylinder

The 1988 - 1992 SE used the same as the 1985 - 1988 cars, the P/N's for servo and master cylinder are identical from 1985 up to 1992.

In 1993- 1995, we were then led into the wonderful new world era of the Delco Moron system, until the V8 and GT3 appeared in 1995/6, along with the Kelsey-Hayes ABS. The system is now obsolete as far as I can tell.

At that point Lotus chose to amalgamate the P/N's for both the servo and the master cylinder into one P/N for a complete assembly, so comparison was made more difficult. Swindon Alan has made some good progress on that, however there was another change for the 1998 MY.

I stand corrected in all the above, but that's how I see it.

 

[internets]

I believe @fsrowsell replaced his Delco ABS system on his SE so he might be able to help, I remember having hours of fun trying to bleed the rear brakes with Felix on his highwing  

Have you tried sending @Jonathan a PM? He has not been on here in a long long while but might respond to an email. Just a thought  

[G_Reaper]

It really does not matter about whether it is SE or standard car. The S4s brakes work brilliantly with the girling replacement. The Vacuum plays a huge part you can adjust the feel using the Euro Switch. I suspect the different manufacturers used by Lotus were purely for commercial reasons not specification. 

Cheers Mike

[Chillidoggy]

Mike, there are master cylinder differences.

Pre-1985 Girling is 3/4", and has a 38/62 split fluid displacement ratio. Post-1985 - 1992 the diameter is 15/16" and 'probably' 50/50, so if you need to move more fluid for larger brake calipers or Hi-Spec 6-piston/4-piston conversions, the later one is preferable.

[G_Reaper]

Adjustable servo power plays a huge part I cannot stress this enough, as both Martin L and I found out hence he tried both Subaru with a huge servo and the much smaller MR2 set up. He spent more time on trying other manufacturers master cylinders and servos I stuck with previously used Lotus spec parts. I developed the adjustable electric vac set up with a reservoir and he manufactured a couple of brass vacuum take off adapters for our inlet manifolds to make the system have triple redundancy for safety. His S4 was fitted with larger front discs and Hi spec calipers my S4s had the standard S4s Brembo set up and the conversion transformed our cars as we worked together to find a solution.

I only offer information from experience not specs, I needed brakes for my S4s so I fitted what I could find and thankfully it worked superbly. I tried to minimise moving away from parts that Lotus had already used and having to manufacture brackets etc to make the installation look like a factory fit.

I hope this helps.

Cheers Mike

[Chillidoggy]

Further to the above reference getting vacuum from the inlet manifold, here's a photo of where you take can the vacuum from. It's the take-off that goes to the charcoal canister, (which would need a T-piece).

The thread is M12 x 1.5, and a brass 3/8" hose tail is available off eBay to fit, I bought one last week.

 

[rizla603104]

So some research for T25 master cylinder shows as the part being 251611021C is that correct?

I have just found a Renault Extra servo on Ebay and bought it. Have I done the right thing?

[davevr6car]

I really do think people are over thinking this conversion.......the best thing is to find the biggest master and servo that will fit in the current location....the rest can be adjusted thru....pressure switches or bleed valves......and you can install a brake bias valve to control the pressure going to the front and rears...this will give great adjustment to your type of driving.  This is why I fitted the Nissan Patrol mater and servo.......if its good enough to stop a 2 ton 4 x 4 then it'll stop an Esprit.

'

 

 

[davevr6car]

Here's an idea of parts:

Wilwood proportioning valve £101.... http://www.ebay.co.uk/itm/Wilwood-Adjustable-Proportioning-Bias-Valve-Distribution-Block-Brake-Switch/280845940737?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649

Nissan Patrol master and servo 2nd hand £69..... https://www.ebay.co.uk/itm/NISSAN-PATROL-Y61-3-0-BRAKE-SERVO-MASTER-CYLINDER-VC05C-M245T-ZD30-1997-2013/132462468616?fits=Car+Make%3ANissan%7CModel%3APatrol+GR&hash=item1ed760de08:g:PpUAAOSw5YNZtDh7

vacuum reservoir £12....... https://www.ebay.co.uk/itm/AUDI-A6-C5-C6-2-5-2-7-TDI-2000-2011-VACUUM-RESERVOIR-TANK-443131541/122703412864?epid=1709554742&hash=item1c91b17e80:g:0BgAAOSwT~ZZtlb4

manual bleed valve £10...... https://www.ebay.co.uk/itm/Adjustable-Manual-Car-Turbo-Boost-Valve-Controller-Booster-Kits-Universal-Blue-C/263384634437?_trkparms=aid%3D555018%26algo%3DPL.SIM%26ao%3D2%26asc%3D49129%26meid%3Da04a6f6bbb4f40a88a640f7ebd707ac3%26pid%3D100005%26rk%3D4%26rkt%3D6%26sd%3D152245941293&_trksid=p2047675.c100005.m1851

vacuum gauge £13...... http://www.ebay.co.uk/itm/52mm-2-Car-Auto-30-0-In-Hg-Vacuum-Boost-Gauge-Pointer-Meter-Smoke-Lens-White/112595498210?hash=item1a3736f4e2:g:80MAAOSwYkBZ22ru

mechanical lotus vacuum pump new £69.... https://www.ebay.co.uk/itm/Cardone-Industries-64-1006-Vacuum-Pump/131704688831?epid=76188755&hash=item1eaa3610bf:m:m0gtBnOetxiJlHHDKEKAfqA

 

The above is an idea of what you need.....you will need some brake pipe fittings......vacuum pipe and some other small bits....but for £300 or so you'll have your conversion.

[rizla603104]

Sounds good - what about the mounting bracket and connection to the brake pedal?

[Chillidoggy]

18 hours ago, rizla603104 said:

So some research for T25 master cylinder shows as the part being 251611021C is that correct?

I have just found a Renault Extra servo on Ebay and bought it. Have I done the right thing?

 

That master cylinder has the same bore size as the SE unit, so that could be the one.http://iapperformance.com/brake-master-cylinder-vanagon-80-91.html

[rizla603104]

Excellent! Any idea where I can get the bracket from?

[Chillidoggy]

The brake servo to match that master cylinder appears to be SKU 281 612 105. That fitted to Vanagons from 1982 - 1990.

[rizla603104]

Brilliant! Thanks - if anyone has a suggestion as to where to get the bracket from - I'm all ears - just checked and that is the servo - if you do have the master cylinder part number. - that'd be great

 

[Chillidoggy]

You've already posted the master cylinder P/N further up.

 For a bracket, you need the dimensions from the servo, in particular the fixing studs spacing, the pushrod thread size, and the diameter of the steel shroud which protrudes rearwards, into the bracket.

[rizla603104]

You did - I see that now. Would a Stevens bracket work without fettling? Also, the connection to the brake pedal is that straight forward?

[Chillidoggy]

Without the servo dimensions I'm not clever enough to say whether a Stevens bracket would work, and the same applies to the pedal linkage.

[Barrykearley]

That’s what a step drill, welder and threaded bar are for ?

[Chillidoggy]

But you'd have to agree it would be far easier to find off-the-shelf parts that don't need to be butchering in a Gloucestershire barn first.

[rizla603104]

1 hour ago, Barrykearley said:

That’s what a step drill, welder and threaded bar are for ?

And if I knew what any of those were - I'd probably agree :-P