Jack Webb big brakes

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timb2117
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What he said :) ha ha. Many thanks James that is exactly it, wish the washer were tighter but it isn't for that reason. The ptfe tape is essentially redundant in terms of sealing the washer doing all the work.

I would have been a  bit happier with a more substantial mating surface but am guessing thats the point its small therefore under high torque, hence does the job. Jack said it has been done for a long long time by Caterham like this so I suspect whilst we all have our own incarnations of this brake kit they all use the same principles/ washers.

thankyou all I appreciate the attention to detail.

timb2117
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Ok got a few road kms and one track day in, reliable but with the supplied ferodo's do squeal a bit coming to gentle stop, however good stopping power, but the rears are still doing more work.

I am going to pop in a valve to the brake line to rear, just as it goes into the tunnel under the bonnet then I can tune out the backs a bit- I am not super feeling on the set up so will fit/ test then forget, without the need to fettle in cab, mid track session. 

Simon.Rogers
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Don't do it!  The rear is under braked.

Pedal feel will change to zero and be pants.

Particularly with the big brakes you need more aggressive pad in the rear to try to balance things out.

 

www.meteormotorsport.com
Richard Price
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"but the rears are still doing more work"

 timb2117,

What makes you say that?

As Simon says, I'd be very surprised if you need LESS rear braking after fitting big fronts!

What pads do you have front and rear? Additionally, what type and size tyres are you running.

timb2117
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Hi Richard I know it sounds odd but -The rears prior to (and after) fitting of the bigger fronts easily and by far heat up more than the fronts, also under aggressive "test" braking the rear locks up sooner.

Sorry not sure about the rear pads but standard caliper, tyres toyo proxxes r888 and wheel size 205/45 r16. - I realise they're big but came on the car and I can get enough heat into the nearly new soft tyres on track for them to work well.

Front pads are the ferodo "race"that came with the brake set up.....Any thoughts

ECR
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When I fitted big brakes many years ago and changed to Mintex 1144 pads all round, I found that the rears locked up even more than with standard fronts. I deduced that the weight transfer to the front was unloading the rears and causing this.

timb2117
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I understand however on "normal' cars the front still locks first, and I think makes it more controllable, do hope I have not upset the balance too much.

John Vine
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Re #18:

...on "normal' cars the front still locks first...

And 7s too.  The IVA examination in the UK specifically tests for this, and if the rears do lock first, the car will fail.

JV

ScottR400D
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Looking at it simplistically, and ready to be corrected, if you significantly improve the front you’ll increase the rate of weight transfer and provoke rear locking by taking the weight off the rear. Improving the rear in proportion will maintain the rate of transfer and balance and keep things in order? 

 

ECR
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Assuming you're not locking the rears in the first place (which I was).... Hehe