Remote brake servos - help required please!!

[v8pete]

Guys,
I need a bit of tutorial advice on Remote Servos. I'm basicall looking at whether it might be possible to change the setup on my Cob (whch runs Princess 4-pots front, Granada Mk II 10 inch drums rear) to operate with a dual m/c Pedal box running (i guess?) a pair of remote servos? The setup up until now has used a good old Marina P/B and Marina servo - this arrangement has never been up to much :-(

Anyway, can anyone advise me please on :

1) How the twin servo approach works - do you simply plumb one servo in line with each m/c ? How adjustable can the setup be made? - can you alter the servo assistance in any way?
2) Where to get Servos & a dual m/c pedal box with balance bar at a good price?
3) Any general advice gained from bitter experiance would also be appreciated!

The other reason for going remote is to get the servo off the bulkhead so that the new exhaust manifolds I've fitted won't try and melt everything as they're currently doing very successfully!

Cheers,
Pete.

[Mutant Rat]

1) Yes - inline installation, one for the front brake circuit, one for the rear. The servos themselves are not adjustable, but of course the brake bias will be adjustable at the balance bar on the master cylinders. A matching pair of servos should give roughly the same boost as each other, so you just need to balance the fron/rear bias exactly as you would an unservoed set-up with twin m/cyls and balance bar. If, for whatever reason, you don't have enough range of adjustment from the balance bar alone, you would need to play with master cylinder sizes.

2) Try: Classicar Automotive for the servos. They do new Lockheed servos for quite reasonable prices.

3) Lotus Elan Plus 2's had twin servos. I've got an old factory workshop manual somewhere that probably shows the installation, but it will be in storage at my other house, so would take a few days to obtain. If you are still stuck, e-mail me off-forum via my profile and I'll see what I can do.

You may find the following link helpful: Plus 2 Twin Servos

>> Edited by Mutant Rat on Monday 1st August 19:25

[v8pete]

Cheers Mutant Rat! - that's exactly the kind of advice I was looking for! Will check out the links (colud be interested in the Elan manual stuff, but please don't go to any trouble as I have a local friend who I'm guessing might well have some details on the Elan set up also - I'll ask him tomorrow).

Cheers & thanks again,
Pete.

[Avocet]

I've a vague feeling some of the old FX4 taxis used a remote servo. I had one on a Relaint once (don't laugh!), it was an old 4-legged one that used Herald front suspension so I put a 1600 crossflow motor in it and then decided tha tthe non-assisted drums all round weren't really up to the job so I replaced the front end with Triumph Vitesse components (these had discs) and found that the pedal effort required was silly - hence the remote servo. Only thing I did find, though was that the pedal travel was vastly increased.

[Mutant Rat]

One thing that might be worth knowing:

IIRC, the only remote servos that are now readily available are the ones made by AP Lockheed. Lotus' were originally fitted with Girling remote servos, but these are no longer available and most second-hand ones are not fit to be rebuilt.

Anyway...the Lockheed servos are sensitive to installation angle. See the diagram on the LotusElan.net link I gave above. If you fit them at too great an angle, they have a tendency to lock on, which can be at best disconcerting, and at worst bloody lethal!

[Purple AK]

Pete.
Are you sure that it is the Marina setup that is causing the problem? I have one on the AK with 4 Pot Jag calipers on the front and 2 Pot on the rear and the brakes are MORE than adequate! So apart from the heat issue (easily overcome with a heat shield) I cant see that upgrading the master/servo setup is going to help. If your brakes are not good the problem must surely lie in the other end Ie: Discs/Calipers and Shoes/Drums! JMO

[Pum]

Way back when ... the Rover P6 was a good source of remote servos. I believe they were Girlings. Few and far between now, but if you did come across a good one ...

[Purple AK]

This may be of interest www.cobraclub.com/classifieds/showproduct.php?product=542

[djroadboy]

I have a nearly new remote Lockheed servo for sale, I used it on my Fiesta racecar for the front brakes as the rear disc conversion was more than adequate un boosted. If using two servos you can get servos with different ratios of assistance to alter the balance. If you are interested drop me an e mail at www.judeperformance.co.uk.

Best Regds