So I know that it's a direct replacement for a 997S to use GT3 calipers but what's required to go with GT3 calipers on a base model car?

I realize there are many who will suggest I just get an S but that isn't an option. Honestly, only because the wife will actually leave me if I suggest upgrading cars. There is no convincing her even if I show her the math of how it makes sense.

I've considered the giro disc but the bigger rotors just don't make up for the larger pad surface. I MAY even do GT3 calipers with GT3 girodiscs for the heck of it.

So do I need bearing carriers/hubs? Front and rear? Can I use the base model 997 calipers on the rear and buy new fronts? Any help would be appreciated! Thanks!

 

Why do you need bigger brakes?

 

Because bigger is better? Just ask justatoy, he has applied this philosophy to multiple aspects of his life!

Actually, my rotors have maybe one more track day on them and i may as well upgrade them. I'm moving to dedicated track wheels in 305 and 245 R comp rubber and I'm going to assume that this will place that much more stress on the brakes. I run good fluid and haven't experienced fade yet but the calipers are starting to change colors so they're getting hot.

My initial thought was to do giro discs with gt3 or cup cooling ducts but I would like to consider all options before throwing my money at something.

Another question: 996 gt3 same hub as base 997?

 

Your base brakes are smaller than the S version brakes so I am not sure Girodisc would have anything for you or even do much. You need bigger calipers and rotos. Yes you could retro fit GT3 brakes on your car.

Are you running R-Compound tires? IF so and you are doing a lot of threshold braking your definitly need more brakes. If you are still on street tires then your stock brake or at least S brakes are fine.

 

I did the gt3 brake upgrade on my base carrera.

You will need 997S hubs for the front and can keep your rear hubs stock. The front and rear 997 GT3 calipers are compatible with the front 997S hub and the rear 997 base hub. As for the rotors the only ones that I found would fit on this setup are 997 turbo front and the GT3 rear rotors worked (although I didnt try any other configuration on the rear).

Another thing to consider might be to just find a 997 turbo brake setup and just get 997s front hubs (probably a cheaper option) and Im not really sure what the difference is but the turbos do have the 6 piston front calipers.

Good luck

 

 

bigger isn't always better, larger brakes will give you better cooling of your rotors, however it will also increase your unsprung weight. Braking is a function of grip/friction, and larger brakes don't mean better grip. Your grip comes from tires on the road and pads on rotor.

If you are running R Comps and need more brakes, try a more agrressive pad, as well you could swap to a steel braided brake lines. The other thing to watch out for is that the brake system may not be capable of handling the bigger brake pistons, a lot more fluid is needed to fill the pistons on the stock GT3 brakes, perhaps a Brembo system may be a better fit.

Suncoast sells a GT3 kit for the C2S, however is a GT3 Caliper with a Turbo rotor, as the offset is different then the GT3.

 

I agree with NorthVan, I did my swap mainly for the way they looked. Didnt notice a big difference in performance.

 

bigger isnt always better, improve "smarter" things on car before going for aesthetic things unless all your after is looks.

youd be putting heavier brakes on the car and not improving breaking as much as if you swapped tires... the brakes on these cars, are fine...

 

My second post I said I was going to wider front tires with r comps.

I'm goig to verify the size of the 6 piston cars master cylinder.

Some of the 'smarter' things I've done is remove all rubber bushings, replace droplinks and sways, CCW wheels on the way, racing seat, schroth harness, roll bar, short shifter, gt3 control arms, rear toe links and locking kit and some of the new pagid RS5 blue pads (which I think may be better than the yellows for typical trackday usage).

Between the smaller wheels and the giro discs (I'll use the turbo model) I think it'll make up for the added weight. The volume of the master cylinder is a concern though.

 

atr911, a GT3 master cylinder fits right in...they are around $350 at Suncoast.

 

you need different hubs. 'S' and GT3 calipers have different dostance between bolts than base calipers.

also check with your mechanic if master cylinder would need to be changed or not. thos work is doable, used 996 GT3 brakes are relatively affordable and are way better than 'S' brakes but will require some alterations, so, good mechanic is definitely required for this, it is not a 'forum' level diy job.

 

BTW for rear calipers you do not need new hubs - you may put 'S' bigger calpers there directly. I do not think it is a smart iidea to do keeping front smaller calipers but rear ones get overheated usually, so, if you use proper front/rear pads to balance grip then you may simply upgrade rear ones.
I would not do it but it is possible.

 

Since GiroDisc where mentioned earlier; they actually have a setup for 997.1 C2/C4, (re-using factory calipers though).
Front discs: size is up from 317 to 340 mm, weight is down ~13%.
Rear discs: size is up from 298 to 325 mm, weight equals stock

http://www.cargraphic.de/sources/dow...rodisc-web.pdf


[EDIT] Re-read and noticed the OP alreaady had considered the GiroDisc's.