Weeksy

iTrader: (1)

Hi all,

So I've treated my 2wd sack to some 6 pot front brakes, and now wondering what to do ( if anything!) with the rears. It already has 4x4 vented read brakes but was wondering if there were any benefits to be had from going bigger diameter or whether it's just not worth it!

appreciate your thoughts as always

Thanks a lot

Weeksy

Caddyshack

I would go MK, MT or Reyland 300 mm conversion using std callipers and use the good brake pads they suggest, it made a big improvement on my car and mine is very light.

All of the above are pretty much identical

Weeksy

iTrader: (1)

Thanks for the quick reply my good man.

I did see the reyland kit, and the 300's fit inside my poxy 16's!

Marc sierra

iTrader: (1)

In what way did it make a big improvement? The bigger brake kit is meant for dealing better with high temperatures. Of course it could be that the fronts brake harder with a certain pedal pressure after you've upgraded them and a bigger kit at the rear gets the front/rear balance back.

Caddyshack

The car feels more balanced under braking, before I had a bias issue I think. I also wonder if my std setup was past its best, not worn but had been on the car 20 yrs. my rears had solid discs too so probably did not deal with heat as well. I would say it also has more bite but hard to say as I now have uprated pads too, the callipers have been refurbed and I have changed over to a normal servo and junked all of the ABS and remote pump etc so maybe mine is not a fair comparison.



The braking ability with a bigger diameter is normally better brakes overall, if not we would probably just have thicker discs and better cooling. Generally heavier or faster cars have bigger discs.

Marc sierra

iTrader: (1)

What do you mean with "the braking ability with a bigger diameter is normally better brakes overall"? To me the function of the brakes is to brake as hard as possible. Even the tiny solid 240 mm discs on a standard 1.6 Sierra can brake hard enough to lock the wheels. The other thing the brakes need to do is maintain the full braking power as long as possible.


Since the kinetic energy is equal to M*v^2, the mass and especially the speed determine how much energy is absorbed by the brakes. Hence heavy cars, and especially fast (and heavy) cars need brakes that can absorb a lot of energy and afterwards quickly dissipate the energy to the environment. Bigger discs have more mass so they can absorb more energy. And the brake surface also rotates faster due to the bigger radius, meaning they cool down faster as well. A bigger disc can also give a higher brake torque to the wheel, but since the tiny 240 mm disc can already lock the wheel this is no improvement that you really notice.


So in my opinion, unless you are fading your brakes, so don't need bigger discs.

Caddyshack

I thought a physics lesson was on the way.

I can lock my brakes more easily now therefore my brakes are now "stronger" and as you point out they are far more fade resistant as I can dissipate more heat.

I can also run stickier tyres in the knowledge I can dissipate more heat and not fade them.

If I decide to do a track day I can go safe in the knowledge that they are less likely to fade.

Marc sierra

iTrader: (1)

Sorry I didn't mean to lecture you on physics, but some people might not know in what way bigger brakes help.

I understand that you've upgraded your brakes with the power you are running and are going to run. But the topic starter might not need the extra capacity on the rear brakes, so it could just be a waste of money.

A couple of years ago I upgraded my front brakes and asked Reyland whether I needed a bigger rear kit to balance the front/rear, but it was not needed he said.

Caddyshack

Gotcha.

I just went for the biggest I could as with 16inch wheels and pretty much 500bhp and same torque I certainly did not want to be under braked.

I am pretty sure that the standard setup all round with decent hoses, good fluid and high quality / properly suited pads would be a good setup for reasonable power cars.

Ridgey

iTrader: (5)

Weeksy
I doubt you need them, but they do look good

ajamesc

I've that kit on mine it's a nice kit very well made

Caddyshack

Mine are 16's too

Weeksy

iTrader: (1)

Ridgey,

You are right fella! I may just go for them dude!

They should fill the wheels a little better if nothing else eh?!

I wonder if he does the discs in plain finish?! My willwood fronts have a different style of groove the rears he sells won't match!

Appreciate the comments fellas

Cheers

Weeksy

Ridgey

iTrader: (5)

I wouldn't worry about disc pattern, as people never notice the difference, I have j hook rears and straight fronts.

3doorcozmess

I wouldn't even bother with big brakes on the back as most of the braking is on the front.

Cheap way of doing it tho is, get some 4x4 rear calipers and buy the 300mm kit from reyland.

http://www.reyland.co.uk/2wd-rear-kits/

3doorcozmess

The kit uses a 4x4 caliper

Weeksy

iTrader: (1)

That's good, I have those already!

Caddyshack

I meant standard 4x4 callipers, I assumed it was a 4x4