2 pot rear brakes

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diesel destroyer
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2 pot rear brakes

Post by diesel destroyer » Sat Oct 19, 2013 7:02 am

Andy Watson popped down yesterday..

After 3 months his custom rear brake set up finally went on

He's using 304mm AP vented discs (same as front) on the back now.. With a Hi Spec 2 pot calliper.. Using 2x38mm pistons and built in spot calliper for the hand brake

The callipers as supplied rely on the hand brake cable pulling in line with the callipers.. And not at right angles to the calliper as MG use.. So I got my friend to strip the callipers and re-engineer them to take a standard MG cable..

Laser cut mounts too.. To mount the calliper

Manual brake bias valve going under the bonnet so Andy can fine tune them on track days
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diesel destroyer
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Re: 2 pot rear brakes

Post by diesel destroyer » Sat Oct 19, 2013 7:04 am

Hand brake cable now fits like this
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Rich in Vancouver
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Re: 2 pot rear brakes

Post by Rich in Vancouver » Sat Oct 19, 2013 7:18 am

That is very slick-Well Done!
Are you planning on producing the brackets for sale?

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Rob Bell
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Re: 2 pot rear brakes

Post by Rob Bell » Sat Oct 19, 2013 9:24 am

Having 304mm discs all round might be a bit of over kill, but would look über cool!!!

Unfortunately, those rear calipers are not standard HiSpec and have been modified to take the MGF rear handbrake cable. And there are only two - Andy's and Allan's! :lol:

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Rich in Vancouver
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Re: 2 pot rear brakes

Post by Rich in Vancouver » Sat Oct 19, 2013 7:14 pm

There is some interest on the other forum of getting a run of conversion parts made up, or alternatively
buying copies of the drawings. Let's see where this goes. If nothing else it would be nice to see the wheels filled with
nice meaty brakes! :thumbsu:
As long as they are set up correctly brakes is one area where overkill can be a good thing!

diesel destroyer
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Re: 2 pot rear brakes

Post by diesel destroyer » Sun Oct 20, 2013 2:20 am

Having an adjustable bias valve under the bonnet means the balance can be maintained..

The mounting brackets are easy.. Laser cut from a cad drawing..

But.. It's the hand brake fitment which is the biggest issue.. As Rob says I only got 2 sets done.. As my mate done them without charging labour.. Asking him to do another 10 sets would end our friendship lol

A few are looking handbrake cable solutions Rich.. If they can mass produce at sensible cost they may well become available
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Rich in Vancouver
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Re: 2 pot rear brakes

Post by Rich in Vancouver » Sun Oct 20, 2013 4:51 am

I find this particularly interesting as a few years ago I made up mounting brackets to install MGF calipers on my ZA-Magnette and modified the ZA handbrake attachment to work with the F calipers. Pretty much the opposite of what you have done and that makes it even more appealing as a project for my F.
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Not exactly laser cut but they did the trick! :D
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Rob Bell
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Re: 2 pot rear brakes

Post by Rob Bell » Mon Oct 21, 2013 9:14 am

How did the brake tests go yesterday chaps? :)

diesel destroyer
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Re: 2 pot rear brakes

Post by diesel destroyer » Mon Oct 21, 2013 10:33 am

Brake bias valve fitted.. Factory one removed..
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diesel destroyer
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Re: 2 pot rear brakes

Post by diesel destroyer » Mon Oct 21, 2013 11:02 am

Due to the poor standard of work on the rest of the car.. We decided to leave nothing to chance and flush the lines fully with 5.1 fluid.. 5.1 was ment to be fitted when the car was built.. But then a lot of things were claimed to have been done but were not..

So we flushed the lines and fitted new 5.1fluid
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Rob Bell
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Re: 2 pot rear brakes

Post by Rob Bell » Mon Oct 21, 2013 11:07 am

And how is the brake bias working out chaps? Hope Andy isn't parked in a Hedge backwards? :lol:

diesel destroyer
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Re: 2 pot rear brakes

Post by diesel destroyer » Mon Oct 21, 2013 11:15 am

We also got both uprated anti roll bars fitted..

Andy reckons already he's noticed a difference with them fitted..

The drop link mounts were modded to make them double shear..

The drop links custom made..
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diesel destroyer
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Re: 2 pot rear brakes

Post by diesel destroyer » Mon Oct 21, 2013 11:23 am

Rob Bell wrote:And how is the brake bias working out chaps? Hope Andy isn't parked in a Hedge backwards? :lol:

We played it safe and set the bias valve in the middle..

The weather was so bad yesterday.. Rain bouncing a foot high.. Testing the brakes properly was out of the question..

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Rob Bell
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Re: 2 pot rear brakes

Post by Rob Bell » Mon Oct 21, 2013 1:53 pm

Dave Andrews has a section on how to set a variable brake bias valve on his website somewhere. Wet conditions are usually ideal: nice and slippery, so that once you've exceeded the rear braking capacity, you are only travelling at low speeds! :lol: I think his method was to left-foot-brake while driving in a constant radius, but I need to look it up again! :)

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Rob Bell
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Re: 2 pot rear brakes

Post by Rob Bell » Mon Oct 21, 2013 2:20 pm

From http://www.colinusher.info/Robin%20Hood/mini.html
Dave Andrews wrote:To adjust the front/rear balance you need to find an open space with little traffic and unscrew the adjustment bolt. Drive gently at around 20-30mph. Whilst turning declutch then brake gently. You should feel the front of the car run wide (understeer). Turn in the adjusting bolt around half a turn and repeat, not forgetting to declutch. Repeat this process until you feel the back of the car stepping out (oversteer). When this happens, lock up the adjusting bolt. Now drive in a straight line and make an emergency stop. The front wheels should lock up just before the rears.

diesel destroyer
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Re: 2 pot rear brakes

Post by diesel destroyer » Mon Oct 21, 2013 4:42 pm

Once again in your debt sir

Thank you

:thumbsu:

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andywatson
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Re: 2 pot rear brakes

Post by andywatson » Mon Oct 21, 2013 6:08 pm

Thanks Rob, i'll give it a go in the local supermarket car park one night. I might get mistaken for a boy racer.

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Rob Bell
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Re: 2 pot rear brakes

Post by Rob Bell » Mon Oct 21, 2013 6:56 pm

:lol: Have fun!

It's safer to have an excess of frontward bias, so bear that in mind when setting the car up: don't be too heroic in making the rears work more!

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