996 rears question!

[AndersS2]

Hi!

i've realised that i've bought the rear 996 calippers on ebay.de.
the PN is:996.352.426.02(red?).
After what i've heard the pistons is smaller but the calipper is the same physical size.
so, in order to have brakes that bite properly, do I need to sell them and buy a 996 front ones or is it ok to use the rear calippers on the front of my s2?

will upload pic with measurements when i'm home from work..

[BRY]

Billzcat does a kit using the rears, I got shot down for asking if they were any good, here.
My main concern was how it would affect the balance from front to rear and that never was never answered.

[AndersS2]

hm, i thought it would not affect the brakebias more than the 996 front calipper.
i've mailed billzcat some weeks ago and he said he did'nt do those upgrades anymore because people found the parts themselves.

[Corey]

Casting is physically the same size, it is just the pistons that are smaller and hence the volume of fluid required to move the piston would be less, so theoretically you would end up with a firmer pedal.
Balance is not really an issue as long as the ABS system is functioning properly.

If I may be so bold to state that you should be able to use (although I do not have anything conclusive to say yes or no) the rears on the fronts, as they should still be better than the stock items and they will be being used around larger discs don't forget.
Try thm and see what results you get, no one knew that the fronts would work untill someone bolted one up.

[kwlw]

Casting is physically the same size, it is just the pistons that are smaller and hence the volume of fluid required to move the piston would be less, so theoretically you would end up with a firmer pedal.

And higher pedal force will be required to stop the car. Working bomb and brake booster is a must

Balance is not really an issue as long as the ABS system is functioning properly.

Not sure about this, especially in track conditions. Decided to go in some special way, like choosing compound of brake pads for the rear .

If I may be so bold to state that you should be able to use (although I do not have anything conclusive to say yes or no) the rears on the fronts, as they should still be better than the stock items and they will be being used around larger discs don't forget.
Try thm and see what results you get, no one knew that the fronts would work untill someone bolted one up.

I'm bolting them , however not on S2, so I cannot use 323x30 disc (diff offset), here is a picture of my rears on the front:

http://www.soften.ktu.lt/~kwlw/brems/996caliper8.jpg

Note, that these caliper accept 28mm thick disc without machining. To put 323x30 (a8) disc, you need to push pins, shear some material form the pads, etc.

Sau

[panzerwagen]

AndersS2, I have the Billzcat1 kit on my car....

And it works GREAT!!! The kits fits under both 17's and 16's easily! It's a damn shame he no longer makes the kit because there seems to be alot of guys in the States looking for a setup like mine.
As for changing master cylinder, or anything else. Absolutely NOT!
Anybody who tells you the opposite is talking out of their ***.
Brake balance is THE SAME. It does not change what so ever.
The performance of the setup depends on the pads you use. Right now the pads I'm using are perfect for a track meet but crap for everyday use. The squeal all to hell when the temps drop below freezing(32°F). I'm going to change them to a softer material.
I have had the occasion to use the brakes in emergency situations and I can say from first hand experience they are an absolute 200% improvement over the standard front brake system. When they say throw out the anchor, it is an apt description of these brakes.

[kwlw]

And it works GREAT!!! The kits fits under both 17's and 16's brakes.

All this is about Billzcat kit, which uses custom brackets and wilwood rotor rings with custom hats. In real life when you don't have THAT good kit, you face lots of things to think about and to invent their own bike .

Sau
P.S. Brake balance do change, however I've heard stories, that you cannot make too much brake pressure on audi coupe quattro rear brakes to make them lock on high speed. Maybe this is your case .
P.P.S. My "kit" doesn't fit under R16 http://www.soften.ktu.lt/~kwlw/brems/r16notfit2.jpg

[panzerwagen]

Hey Anders, in reference to the pix you posted....

what is the 37mm alluding too? I can't seem to reference what is 37mm.

[AndersS2]

hmm, so the pedalfeel will be improved ey? hence it's smaller amount of liquid that should push the pistons together.
But do you guys have an opinion that it might work with the this setup?

*996rear calipper (duh..)
*rs2 brackets
*a8 disc (323x30, modding the caliper to fit)

since that is what you use with the 996front "kit", and the physical size is the same, shouldn't that work in theory?
If someone know the measurments i could dig up some 2-piece discs or have some custom made if i find someone which does it.

i am positive to try it, but need the correct measurements, if anyone knows what i need.
Doesn't matter if it will fit under 16's, it'll just have some bbs 18"s all year :mischeif:

[AndersS2]

what is the 37mm alluding too? I can't seem to reference what is 37mm.

it's form the center of the bolt hole, to the end of the "pin" that is standing out from the calipper. hope you understand it. hehe. my english explenations isn't very good at all

[kwlw]

hmm, so the pedalfeel will be improved ey? hence it's smaller amount of liquid that should push the pistons together.

You will require 2x force to push pedal.

But do you guys have an opinion that it might work with the this setup?

*996rear calipper (duh..)
*rs2 brackets
*a8 disc (323x30, modding the caliper to fit)

It's NOT NORMAL 996 REARS! it's 996 GT3/TT! If someone will try to fit normal 996 rears on RS2 brackets - there can be problems.

It will work with 323x30, however you will need to modify not only the caliper. You will need to shear quite a lot from brake pads. This caliper accepts 996 front pads BTW . So if you will go this way - A8 disc will fit.

Sau

[AndersS2]

ok, 2x the pedal pressure, got it. but how is that pedal pressure compared to the ordinary 996 coversion?

kwlw: so you say that it's like braking with an old non-servo-racing brakes?

Will that moddig say that i loose ~5mm of the pads? since the disc is 30mm, and the caliper itself is supposed to take 25mm discs (25+5=30?!), and i would have to file off 1mm on each of the 4 cylinders ((not the brakepistons) that is carrying the pads or something)?
lot of questions, but you guys know so much and i know so little.

thanks for the frontpad tip btw!

[panzerwagen]

"You will require 2x force to push pedal." *rolls eyes....

Oh boy is that one for the books! NOT TRUE!!! I HAVE THE SETUP ON MY CAR NOW! The pedal FEELS THE SAME! It's the same as if you had put in new pads on your OEM calipers. Once the pads are broken in you won't even know the difference.
You are getting alot of info that is in-correct.
Contact me off Forum! I have pix & info if interested.

[panzerwagen]

Anders, this is mine mounted on my car....

As you can see the hub/rotor/caliper and ss line.

[AndersS2]

wow! does look nice with the 2-piece rotor me thinks!
nice pic panzer. got more?

but i wonder if i could get me a 2-piece rotor even bigger thats not custom made?

read somewhere that a 2-piece is lighter than a original a8 disc (in this comparison), and lighter means better handling/acceleration. but they do cost some more "£" dont they?