BlackRocket

After researching aftermarket brake kits it appears that the Wilwood's are the best value priced. The front kit using their 14" disc is only a little more than the 13".

http://www.wilwood.com/BrakeKits/Bra...axle=Front+Kit

To save cost was planning on using their D8 calipers on the rear.

http://www.wilwood.com/BrakeKits/Bra...tte&option=C-3


Those that have done this can the bias be adjusted out effectively using a proportioning valve?

Thanks!

gkull

When ever you are shopping for brakes the thing to look at is PISTON AREA. Those super lites that you posted have 4.04 Sq inches. The d8 6 are. 5.51

It is dumb to decrease your stopping ability. What is the Sq of our stock c3 brakes?

BlackRocket

Piston area is less... but not my question;

Area being pi x r Squared...
C3 Front stock piston diameter is 1 7/8" = 5.52"
Wilwood 6SP are 4.04" and 4SP are 4.80"
Comparing Wilwoods to the stock calipers is Apples & Oranges. The clamping force is engineered in... Wilwoods pad area is 8" on a 14" disc which multiplies the friction/leverage exponentially. Wilwood's have staggered pistons for more even pressure preventing pad galling. A proprietary piston design prevents heat transfer resulting in fluid boiling & brake fade.

C3 Rear stock pistons are 1 3/8" = 2.96"
Wilwood D8s are the same at 3.00"

The Wilwoods are a great value when compared to Stoptech, Brembo, Baer or AP Racing. Many teams use them on dedicated race cars without any issue. My question is that given a C3s brake system can the bias be proportioned out using a much less effective rear brake system and different tire size/contact area front/rear? May be tough to balance??

Thanks!
B-R

cagotzmann

I run Wilwood D8-4 with the factory size rotor, but to aid the bias I use Carbotech XP20 front and XP12 rear.

So I would think you could get what you want if you add the pads friction coefficient are part of the formula.

Jason Staley

I don't think you will be able to balance that particular combination out, it's just too mismatched. Why not stay with one "system" and use DB8's or the Superlites on all four corners? At least you're starting from a fairly balanced system either way and adjust the balance to your liking using pad compounds.

ignatz

I'm intending to be helpful here so don't take this wrong. It doesn't matter what the pad area is, the force on the pad is due to hydraulic pressure on the pistons. Hence lbs/sq-in pressure in your system times the area of the pistons pushing on the pad is the actual force applied. Unless you are going for the hyperbole of "exponentially", the torque due to disc diameter is approximately linear with the diameter. You might try running out all the numbers and post your math after doing a search.

There have been numerous posts on the ineffectiveness of the rear brakes. I suppose decreasing the front area is one way of changing the front/rear bias. As to your proportioning question you can certainly modify whatever you come up with with a valve. I ended up adapting a set of Wilwood front brakes to my rears and inserting a proportioning valve. I also discovered that the valve didn't meet its advertised transfer function. That required that I actually measure the pressure in my system with the valve in place.

In my many years on this planet I've learned the hard way that trying to be too clever about reconfiguring a system usually comes back to bite me! You probably ought to listen to Mr. Staley just above.

gkull

With good tires and good pavement you are going to get the most front weight x-fer. So you need the highest front braking ability. The piston size and then compound are high on the list. The sweep area of a bigger diameter, compound size, tire grip come into play.

I don't have a bias problem with or an adjuster with 7+ inches of front piston area with 295 front slicks or 275 front tires of GT1 front wildwood calipers and rotors.

I use the bp-20 or bp-30 compounds. You want the fronts to lock first under max weight x-fer

14 inch rotors are not going to slow you down without enough clamping force.

I've watched some in car videos from cars behind me doing the max braking into turns and it was not until I turned into a turn that you would see smoke coming off the inside unloaded tire because of lateral weight x-fer. trick systems of on the dash bias control are only needed on real race cars because of the ever changing conditions