Brake upgrades for track use, rear discs, 4 pots?

[MK999]

You cannot achieve the same straight line speed with a lower cornering speed, unless that car is topped out at the end of every straight, where does the extra acceleration come from?

And how do you 'work harder' on the straights, than being WOT?

With a poor setup you will have less grip which forces you to brake earlier, and for longer, but at a much lower rate so much less energy in the braking system.

[Iain]

Calm down Mr Merit, I've not discounted or ignored any advice I basically wanted to know if upgrading to 4 pots or larger discs would potentially lead to a solution, the answer is yes, therefore I am happy.

I tried to order CL5+s and failed, so I rang several suppliers of Mintex pads who couldn't get 1155s, I think they said that compound was custom made for the Vauxhall pads. So I bought a different pad and put up with crap pedal feel for a few trackdays, I'm not gonna put in a CL5+ order at the same time as buying the other pads am I...

And other than the explanation of cool down laps and the auto adjusters messing about, I see no reason to move to rear discs still too

[meritlover]

You cannot achieve the same straight line speed with a lower cornering speed, unless that car is topped out at the end of every straight, where does the extra acceleration come from?

And how do you 'work harder' on the straights, than being WOT?

With a poor setup you will have less grip which forces you to brake earlier, and for longer, but at a much lower rate so much less energy in the braking system.

its perfectly reasonable for 2 cars with different brake setups to be doing the same straight line speed on the right track. especially since most are geared for 110-120 max

this is where the advantage comes from. yes the car with more corner speed will be ahead, but the top speed can be the same because he reaches it quicker.
having been to many track days and watching many people with budget cars 'drive quick' its no wonder many of the same people complain about brakes and how they could go faster with better brakes. There is often nothing smooth or consistent about how they are driving and all the energy as expelled through brakes rather than just taking a smooth clean line and lifting off before the corner. Not just throwing an anchor out the window last minute and hoping for the best.

VX220 and Elise track days are priceless for this.

[Adam]

You clearly brake too much, not got fade in mine yet.

You clearly can't carry enough speed through the corners to justify braking at the end of the next straight

[Hobbit]

You clearly can't carry enough speed through the corners to justify braking at the end of the next straight

I'm guessing the drivers of the caterham/vx220/s2000... Other good handling cars would disagree that mine doesn't do corners.

http://www.youtube.com/watch?v=PorTDHSnazo&sns=em

[turbojolt]

You clearly can't carry enough speed through the corners to justify braking at the end of the next straight

oooooooooooooooooooh burned!!!!!!

[Adam]

I'm guessing the drivers of the caterham/vx220/s2000... Other good handling cars would disagree that mine doesn't do corners.

http://www.youtube.com/watch?v=PorTDHSnazo&sns=em

Lol. Interesting to see what lap times are like compared to a 4pot. Can't really draw a conclusion on a wet day like that one. Anyway that's another thread.

[Paul]

Christ Iain's trying to build a cheap track toy not break lap records. He has a great car and has found that he is suffering from brske fade so has asked what other people are using and what results they have. How we've got into a scientific debate about 'mu' and clamping forces and iain's driving lines!

If he was serious about trackday-ing and lap speed records then a) he wouldnt be doing it in a Nova and b) he wouldnt be taking advice from us.

He is building a Nova not a Ginetta cup car!

[Hobbit]

^ this.

[Southie]

Iain are you running bias brakes or a standard Nova master cylinder? Might of missed this somewhere.

If bias have you got the rears setup with too much braking?

If standard then are the adjusters too tight?