Marina Servo Diameter

[andyf]

Re: Marina Servo Diameter

Back in the 80's my friends Marlin was far too front brake biased - not surprising really

His solution was to fit a remote servo in the back brake line only
Made a massive difference - the brakes felt excellent

I'm busy building MY Marlin - I threw the Marina pedal box away and I'm fitting two master cylinders and a balance bar

I don't expect to need a servo

I have considered that but biased peddle boxes are expensive. What are you using.

[duncan]

Re: Marina Servo Diameter

I have considered that but biased peddle boxes are expensive. What are you using.

I just made a bracket for the two master cylinders and the brake pedal - then I made a simple balance bar - if I need to change it I will make a new bar

The Marlin one is using a "pendant" brake pedal and is not finished yet

This is the brake system I made for my "Device"

My Device is 800 kg with hugely more power than a Marlin and the brakes are fine

[andyf]

Re: Marina Servo Diameter

@Duncan, That looks a lot simpler than the servo delete peddle boxes I've seen. I think I'll take a look at my cousin's stock car as I think it has a similar setup.

[duncan]

Re: Marina Servo Diameter

Hi Andyf

That was with a floor mounted pedal - which the books say is better

For my Marlin I'm going for a pendant pedal - pivoted at the top

Mainly because it moves the master cylinders up higher - away from the Torsion bar - and just easier to get to

[andyf]

Re: Marina Servo Diameter

@Duncan, Yes that's what I was thinking too

[HairyDave]

Re: Marina Servo Diameter

In the Haynes Locost book, there are plans for a twin-cylinder floor-mounted pedal box with a balance bar. Also car builder solutions show one with remote adjustment, Non sva though. I love the idea of pendant pedals Duncan.

[andyf]

Re: Marina Servo Diameter

So if I go that route what size master cylinders should I go for?

[duncan]

Re: Marina Servo Diameter

So if I go that route what size master cylinders should I go for?

I'm going with 3/4 inch - cylinders - Trojan Trailer cylinders and a pedal ratio of 6:1

This works well on my "Device" - which is 805 kg - but does have larger Subaru brakes

You can get smaller cylinders and you can make a new pedal to change the pedal ratio

I treat this as a bit of suck it and see - the same with the balance bar

[andyf]

Re: Marina Servo Diameter

I'm going with 3/4 inch - cylinders - Trojan Trailer cylinders and a pedal ratio of 6:1

This works well on my "Device" - which is 805 kg - but does have larger Subaru brakes

You can get smaller cylinders and you can make a new pedal to change the pedal ratio

I treat this as a bit of suck it and see - the same with the balance bar

I have done some googling and 0.625 front the 0.7 rear with a pedal ratio of 6:1 seems to be recommended. 0.625 would be 1.6 times more effective than the 0.75 which would make up for the loss of the servo. I measured my existing pedal and it has a ratio of 3:1 which probably explains why a fair amount of force is required to stop it.

I also came across this which looks like a neat idea to replace the servo, fix the pedal ratio and go dual circuit without having to replace the whole pedal box. Just need to check that it will fit in the space available