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The wilwoods need flow the 6.25 size just won't push enough fluid?!

Thought this made interesting reading. Master cylinder section especially.

http://www.centricparts.com/files/Centr ... _Guide.pdf

I've got an excel spreadsheet with all the formulas. You pop in your pedal ratio. Forces. Master sizes. Caliper specs and some other stuff and it will tell you what the brake balance and end force at the wheels.

The setup I have now is about 300lbs less force at the caliper compared to maximum stock
my brakes were very powerful so it shouldnt matter to much. But you have to remember its not going to be that far off cos the swept area and pad compound co efficient is difference i can press my leg rather well from the basket ball / mountain biking training I used to do. And I don't have the 27 year old nasty flexing servo assembly to mess up all my pedal feel.

Its when I increase the front and rear brakes that this stuff will come good. At the minute with the stock effort they are ok but will be immense when I get 300mm discs and 1.41in calipers.

I do hope I got this right though. Rally design recommended 0.7 with the powerlite calipers I have. And it seemed right on he spreadsheet too..

e21-Mark wrote:Thought this made interesting reading. Master cylinder section especially.

http://www.centricparts.com/files/Centr ... _Guide.pdf

I've read that 900 times now lol

If anyone thinks I've got it wrong I am more than willing to be educated


1.38 x2 front calipers
1.33 x1 rear caliper
6:1 pedal ratio
100lbs input force
256mm disks all round
Distance between masters is 2.5"

P.s I really hate messing with brakes.. Its a nightmare job.

I recently spent about 8 hours replacing a cylinder on my pedal box, absolute nightmare to get at, even with flexi hoses for the feed pipes. That's in the slug with no interior in the way! Try to find a way to assemble it all off the car then bolt it in place. Also bear in mind where your reservoirs will be for topping up and bleeding purposes.

I think you may have trouble with your balance, I have 0.625 on the front circuit, 0.7 rear. Powerlites on the front and golf/A3 sliding calipers on the back. Calipers need pressure not flow, nice solid pedal that hardly moves is what you want. The bias box is dialled all the way towards rear, and I have the bias valve in the rear circuit almost fully off too, even then the rears can easily lock. There's less weight in the slug but even so I'd be wary. Make sure you have a wide clear stretch of road to test on and get someone spotting for you when you really test them so they can tell you if the rears are locking, it's not always as obvious as it should be until it's too late and you spin!

Jim what pedal ratio are you running? you must have a 5-1 then?

Think it was/is 6:1 but lost in the mists of time.

You can do all the sums you want but when you try it you will probably want to change it!

I'd go with 6.25 on the front circuit so you don't need as much adjustment via the valve in the rear circuit.

Just losing that bloody awful linkage will be a marked improvement over standard. The brakes on my track e30 are nothing very special but it's like hitting a brick wall compared to MIB.

Ok I should listen.. I'm tired of number crunching. Ill order a 0.625 as well and fit that first.

Well I took my old pedal box out... And plonked / jammed the new one in.. Access to it seems ok..

Cut some brackets off. Welded up holes and fresh paint.

Before



After

Nothing like a fresh bit of paint

Nice.

Certainly does make a big difference..

The new paint is lighter then the old and needs to age a bit. So this means ill have to do under the bonnet too so it matches.

Not going to be fitting the sound insulation on the bulk head. Hopefully it won't be too loud. Just like how it looks with no tired old insulation.