Dual 7" Brake Servos

[Peterx]

Hi David (?),
that's good news. I have one on order with Mike and look forward to trying mine out in the new year.
It'll be a couple of months as my car is also SORN for the winter and is awaiting the fitting of it's new engine to be fitted.
...peter

[copperleaves11]

Hi Peter. I know it's early days but I 'm fairly sure that everyone who's taken the plunge will feel as I did that the improvement in pedal feel is what has been missing from the original set-up.It will vary from car to car, how much work is involved, as I said initially. My original servo was mounted on a projection from the front of the bulkhead and I chose to grind this projection off and fabricate a plate which fitted in it's place. This allowed me to fit the new servo approx 2 inches closer to the bulkhead, so no alteration to brake pipes were needed (I was quite proud of the neat original pipework). I'll be interested to hear anyone else's findings, although I expect them to be favourable. Regards David.

[greatoldone]

Re: Dual 7" Brake Servos

I forgot all about this thread over here. I too have fitted my dual servo, and the improvement is amazing. The ford MC is bolted on via the adaptor plate Mike designed:



I made a new adjustable 'pin' for the output rod:




The only other things I had to do to make it fit was lengthen the feed lines to my remote reservoir and change the vac hose diameter to suit the elbow on the new servo.



IMHO, the brakes a perfect now. You don't have to stand on them just get her to slow down - a slight push with your right foot and you can immediately feel the brakes bite and the speed fall off. I'm very happy with it, and I'd advise any Marlin owner that isn't happy with their brakes to consider this as a cheap and easy way to upgrade their system.

http://www.greatoldone.co.uk/blog/2012/1/23/would-you-like-to-see-my-etchings.html

[Mike]

Re: Dual 7" Brake Servos

To add some weight to the positive response to the fitting of the Dual 7" servo, the following may be of interest.

Andrew Curtis has just called to say how thrilled he is with the new Dual 7" servo in his BMW Sportster set up. He is another person who says it has transformed his car.

The difference this time is that Andrew has access to a disused airfield behind his farm, so he has been out and conducted some "semi-scientific" tests.

Travelling at a constant 70mph, he braked at a fixed marker point, and measured the travel distance before coming to a complete stop, braking as physically hard as he could.
The average travel distance of the 4 tests with the original Metro servo was 210 feet.

Braking hard, but under control, with the new Dual servo the average distance was 103 feet.
Braking as though in an emergency with front wheels beginning to lock up was 85 feet.
This was a one off test though as he did not care to waste his tyres, but felt he knew now there was a point at which the wheels would lock up at the front.

Not only is he thrilled with the improvement in stopping distance, but with the 'feel' that he now has. He feels he can brake hard in control without excessive pressure, and know that there is more left before the wheels begin to lock up, but in an absolute emergency it would be there if required.

These are the first empirical tests which actually prove the anticipated benefits of changing the Metro servo for the Dual 7" servo.

Another very satisfied adopter.
Good luck to all who follow.

Mike