Salazar

I am thinking about putting TT brakes on my 1999 996. LA Porsche sells the calipers and rotors but not the hubs/carriers etc. Does anyone have a parts list and part

Alon

Ah. I was waiting for someone to ask this. OK, I need to know what has to be changed to use the TT or GT2/3 calipers on my C2 (is Salazar's car a 2 or 4?). I assume that this is much easier to accomplish on a C4 (since the abovementioned cars use the C4 chassis) and I understand (or assume) that the Hub Carrier must be swapped out for one that can hold the TT or GT2/3 caliper in the right spot (or perhaps not?) but if in fact the hub carrier does have to get swapped for the TT GT2/3 hub carrier, how will that work with a C2 front suspension? I hope the answer is not that I must then use C4, TT, GT3/2 front shocks and springs. Sorry for not answering your post Salazar but maybe we can both learn something from this.

Salazar

My car is a C2. To answer one of your questions, the front hub/carrier has to be replaced. I hope that somebody has an answer for the rest of your questions.

Alon

If we know that the hub carrier must be changed, I think that it's safe to assume that we would have to use the TT, GT2/3 hub which was designed to work in a C4 chassis. If that is the case then I will not be able to use C2 front shocks and springs and that will be an issue for me. Anyone?

Karl S

The hub carrier and wheel bearings must be changed, plus a couple of other minor parts that I'll look up when I get home. This will work on a C2, not sure about a C4 but I assume it will as well. You don't need to change any other suspensions components like springs or shocks to do this swap.

I've heard the easier swap is to install the big red brakes from the Boxster S, which is supposed to be a straight bolt-on for the C2. I went the GT3 conversion route because the Boxster S wasn't out when I did mine, so I don't have any first hand knowledge of this but I've seen a couple of posts on this board, indicating that it does work.

Karl

Alon

Firstly, if the hub carrier must be swapped out for the TT one, it should be very easy on a C4 because the TT is based on that chassis. It's the C2 that would be harder because the TT hub carrier (assuming that it uses the same suspension as the C4) uses different shocks and springs versus the C2. The Boxster S has the same exact calipers as the C2 or c4 except that the Boxtser S' are red, the C2 are black and the C4 are silver. So you have a C2 with GT3 brakes? When you say GT3, do you mean 1999 GT3 or 2004 GT3 with the six piston?

Loren

Karl S,

The Boxster "Red" brakes are the same size as the standard C2/C4... just red. I agree the better brake setup with hubs is the GT3 brakes. I think you must also use 5 mm spacers on the front to clear the calipers with most 18" wheels.

SPR

I was just about to say the same thing Loren, but you beat me to it!

salilymay

Karl: I see you are from DC. I live in Chevy Chase. If you can find the part numbers or any other info. it would be greatly appreciated. Would like to confirm that the only parts I need to order are the hubs and bearings. The BIG reds and calipers are sitting in my garage but i dont want to start the project over a weekend and then (on Sunday afternoon) find out that I dont have all the parts. Salazar.

ben in lj

" I agree the better brake setup with hubs is the GT3 brakes. I think you must also use 5 mm spacers on the front to clear the calipers with most 18" wheels."

yes, you do need the GT3 calipers and no i didn't need spacers on my carrera 5 spoke wheels.

that said, anyone interested in buying my 4k mile old GT3/TT brake kit WITH wheel carriers, rotors, pads, etc? i'm thinking about getting some more serious brakes even.

Karl S

OK, here's the scoop from PET.

The GT3 and GT2 use the same parts. The TT uses all the same parts except for the wheel carriers, which are different. Here's what you need to convert a C2 to GT3 or GT2 (non PCCB) brakes:

L wheel carrier - 996 341 157 91 (1)
R wheel carrier - 996 341 158 91 (1)
wheel bearing - 999 053 042 07 (2)
tension bolt - 996 341 131 90 (2)
bearing cover - 986 331 661 20 (2)
wheel hub - 986 331 605 20 (2)
5mm spacer - 996 361 605 90 (2)

The spacer is optional depending on what wheels you are running but it is required for the Sport Design wheels which were standard on the GT3. It is not required for the GT2 or TT wheels. Can't comment on any others.

The TT uses different wheel carriers for AWD, so I suspect the same would be needed to covert a C4 to use the TT calipers. The TT wheel carriers are:

L - 996 341 165 05
R - 996 341 166 05

all the other parts listed for the GT3 are the same and all are needed to do the conversion.

If you have a set of TT calipers and rotors, check the part numbers. The standard TT calipers and rotors are the same as the GT3 and therefore should work fine with the GT3 wheel carriers listed above. The standard TT calipers are:

L - 996 351 429 10
R - 996 351 430 10

These of course, will also work with the TT wheel carriers which is what you'll need if you're converting a C4.

Hope this helps, let me know if there are any more questions.

Karl

Cydog

Will the above list allow you to put stock TT calipers on a C2 without changing the rotors, or do the rotors need to changed to TT rotors as well? Does this modification affect the ABS or PSM system in any way which would require a modification of any sort to them?

ben in lj

You need to change to TT (13") rotors with those calipers and wheel carriers. My (C2) PSM and ABS have not been affected by the upgrade to TT/GT3 13" front and rears.

Oak

Check with a board member "Ruey" I know he has done this mod. I sold him my turbo carriers and brakes.

deputydog95

I'm digging this thread up from the past

Does the master cylinder need to be upgraded for the GT3 brake swap?