Question about brakes

[Zdster]

I have looked around and havent really found the answer to this question:

What is the benefit of putting on larger brake disc onto a vehicle?

My understanding of brakes and braking systems is that the disc is connected to the hub (and therefore the axle) while the caliper applies braking force (through the pad) onto the disc and hence slows the car. As such, wouldn't the best thing for a brake upgrade to be an increase in pad size (and therefore caliper size) which applies more surface area and braking force onto the disc?

Any help in explaining this (through a diagram or otherwise) would be appreciated.

[jamchen]

i don't know my knowledges are correct or not but just to give you a gerneral idea.
yes, the thing you said about the braking system is correct... the pads are basically sqeeze the rotors via the calipers... but size of the disc and caliper have to be balanced in order to get the optimum result. by simply swap with bigger rotors and use original calipers you simply wasted the excess surfaces in rotors that are not covered by the calipers. so that's why if you are going to upgrade your brake system for bigger rotors, bigger calipers are always essential...
generally, if yo do not race/track cars,,, by swaping better pads are sufficient to give you improvements over brakings (but they tend to eat up discs more quickly)... if that's not enough for you, then change to better rotors which are the same sizes to the OEM one( they are better because the materials used are better...) like slotted or drilled...
the next then consider to change the whole set... you may want to have twin piston calipers... (like the MDX),.. or even 4-piston calipers... but most likely they will not fit into stocko rims

in addition maybe change the brake lines.... they will deliver actions more quickly to the braking system...

but, as i said,,, it all depends on how you use the car...
corrections welcoome! :thumbsup:

[Zdster]

Well that was very informative. So generally one needs to find a balance when upgrading - bigger discs should theoretically be used with bigger calipers/pads. Even on a stock setup isnt it worthwhile to upgrade calipers alone (at least theoretically)? I ask this as when you look at how much surface the pads seem to contact on the disc it does not seem to be that great :confused:

[sivic]

if you upgrading brake size you have to change everything - disc, caliper pads.
if you just get bigger discs the calipers wont clear them. even with a kit to move the calipers out there wont be an increase in surface contact. just doing the calipers, providing they fit whic they prob wont ( knuckle assembly etc) will mean the discs will heat too quick/much and warp.

[type one]

your post is a bit chicken and egg...

bigger rotors are used to accommodate bigger calipers - this is the only purpose of bigger rotors... Bigger calipers on the other hand are used to stop the car better than the existing caliper.

pure and simple, if you want better stopping power for reasons known only to you then you will need a more effective caliper ie single pot to a larger single pot or a two,four,six or 8 pot caliper and hence a bigger rotor is needed.

[sivic]

exactly. calipers and discs are partners in crime.

[Zdster]

Thanks for the info. guys. Not actually in the market for new brakes but I have been thinking about this issue for a while and had not found a good answer.


So really the only good reason to upgrade the disc (without upgrading the caliper) is that the material and cooling efficiency of the current disc is not as good as an aftermarket product. The only reason good reason to upgrade the physical size of a disc is to accomodate new calipers (which are presumably bigger?).

Thanks for the helpful info.

[flyhonda]

exactly right...how bout get some lovely mugen calipers...they look super sweet!

[ekslut]

exactly right...how bout get some lovely mugen calipers...they look super sweet!

Mugen calipers? Have you seen them? They look exactly like stock ITR calipers but gold. Now spoon calipers look nice :D mmmm.....4 piston......

[Zdster]

Someone want to lend me some money :D :p . Those things are worth a fortune.

[tinkerbell]

Any help in explaining this (through a diagram or otherwise) would be appreciated.

start here: http://www.stoptech.com/technical/

particulary here: http://www.stoptech.com/whitepapers/brakebiasandperformance.htm

[Zdster]

Thanks for the links ;) but I think that I now understand everything. Will check the links anyway :thumbsup:

[aimre]

Umm i belive a larger rotor leads to a cooler rotor (larger surface area and more than likely better cooling properties ie slotted/drilled and diffrent vanes on the inside of the rotor itself.)

And since cooler brakes are happier brakes (to an extent) a larger rotor would help

[smoknhothonda]

I kinda disagree with a lot of things posted on this thread.

A bigger rotor does increase the braking performance, and in my case I could retain the OEM calipers.

I had recently fitted a Front End AEM Big brake kit to my 95 Honda Accord (305mm slotted rotors) the kit came with adapter brackets for the calipers (which retains the OEM calipers) and the performance was out of this world compared with the stock rotors. (I already had a set of EBC green stuff pads fitted)

Admittedly I did replace the hoses with a stainless braided kit, and the rear OEM rotors for Brembo slotted/drilled items, but it was the AEM big brake kit that made such a dramatic difference.

Sure a 4 pot spoon caliper system would be great, but have you priced one?!? your looking at around 1.5K just for the calipers!!!

I installed the AEM, Brembo, and goodridge hose kit for under 1K and for the money it has been the best bang for your buck mod done to my car yet.

For a everyday car, that sees some hard driving and the occasional track day this setup would be adequate :thumbsup: