Jay Cartay

iTrader: (3)

I was just thinking about this while bored at work. I'm after some 6 pot APs but I want a 356mm kit. If a 330mm kit came up I might be tempted if it was cheap enough and I could switch it to 356mm in the future.

I'm told these kits use the same calipers but that's got me thinking surely if they use the same caliper, you won't be applying a larger pad surface area to the bigger discs. That seems odd. The mounting brackets would just space the caliper out further from the hub but there would be no difference otherwise if this is correct.

Can anyone shed any light?

Don Clark

Revised Post
The 356 kit will probably have larger diameter bells, keeping the width of the brake contact surface roughly the same.

By moving the caliper outwards you increase the Torque capacity of the caliper

The torque capacity of a disk brake with two pads can be expressed as

T = 2 μ F r (1)

where

T = braking torque (Nm)

μ = coeficient of friction

F = force on each pad (N)

r = mean radius (from center wheel to center pad) (m)

legb4rsk

Hey Don,could you please repost that.The first part was ok but then there seems to be some kind of interference & it all went to $%*£.

1509joe

iTrader: (2)

Was sort of thinking that myself yes or no would suffice

bustaMOVEs

iTrader: (31)

Big in not always better for usage, for yours a 330 kit would suffice, only the bigger disc and bigger caliper would be more capable at higher speed like 150+mph etc.
A lighter set up is what you need.
I think adge put up a set of AP 4 pots which would be perfect for sprinting

AS Performance

iTrader: (4)

most of the std kits available use differing thickness for the 2x kits also, normally 28mm discs for 330 and 32mm discs for the larger kits.........

as above depends if its for "show" or "go" (or stop in this instance........)

we do various custom offerings to suit more specific applications as well as the generic AP Racing "factory" kits, etc.

rickybobby

I have a question based on this topic.....sort of.

My blob currently has Brembos front/rear. Drilled/grooved discs with CL5 pads up front, standard discs with Cosworth Streetmaster pads rear, with braided lines and 5.1 fluid.

I've run this setup for 2 years, around 5000 miles and at my previous power level of 335bhp I found it more than adequate on the road however, now the power has been raised to 418bhp I'm finding the brakes a tad lacking. By that I mean that I get good initial bite but if I ask for more I can hear the brakes being over worked and I dont feel much difference in braking force.

I plan to do a track day or 2 next year but the car spends 99% of its time on the road. My question is, should I look to a different disc/pad combination or spend a large portion of £ on aftermarket calipers?

I see people talking about the AP 4 pot 330mm kits but struggle to see how they can be much different to the Brembo 4 pot 326mm I already have? Do the AP have larger pistons or bigger pads? Or should I be looking at the KSport 356mm kit?

Sorry for all the questions, its just a big outlay to get wrong.

Jay Cartay

iTrader: (3)

I wouldn't bother with a 4 pot set, what's the point when I'm already running Brembos and PF two piece discs?

I want it for track work, show is not important to me in that regard. I just want it to stop as best it can and resist fade. I already run Motul RBF fluid and I believe I'm getting the best out of the Brembo set up, bar going for more aggressive pads. If I do that though, they won't be so good for hillclimbing where you need pads that work well from cold.

Tidgy

track work then AP and be done with it.

bustaMOVEs

iTrader: (31)

If mostly road car, then save your money and buy 'genuine' brembo discs all round (they have a better mix of grey iron than the cheaper discs you find and will have more efficiency in the pads working with a quality disc) and fit the cl5 or 6 all round.

I've ran brembo calipers in a heavy newage on rc6s and drove it quite hard and it held up brilliantly.

Cheap discs with a unknown mixture of steel, grey iron is not as good as a proper disc.

That's my opinion anyway.

bustaMOVEs

iTrader: (31)

Buy correct pad s for the work, like carbotech etc, tbh I see nothing wrong with brembos with right set up, getting a bigger caliper todo the same work won't be noticeable apart from weight.
But a big caliper does look Gucci.
I was going to get a 4 pot AP kit, but stumbled upon a friend that did me a deal on some 6 pots that was hard to refuse otherwise I'd of gone with the lighter option.