justin

I need Porsche parts numbers for the items I need to convert my 80 model over to big reds. Front only for now. I thought it was 993 front rotors? I dont want to swap my spindles.
TIA

Mark

928 Specialists (928gt.com) has kits on their website.

justin

I know I want the Porsche part numbers. I am going to try to piece a kit together.
TIA

Mrmerlin

Hi from the PET--- L caliper Twin Turbo 993 351 425 10 , R caliper Twin Turbo 993 351 426 10,
L rotor TT 993 351 045 10 , R rotor TT 993 351 046 10, front pads Turbo 993 351 949 00, these parts bolt on to a S4. I am not sure if these part numbers equate to red calipers as there are a few different choices Black, Silver, Red, and possibly Yellow

ROG100

Justin,
Are you going with "big reds" or S4 calipers. I have S4 calipers painted and ready to go.
Roger

Mark

My bad, justin. They list most of the parts numbers you are looking for (check the 'drop down boxes' towards the bottom of the page.

justin

Mark, thats ok,mrmerlin, will those part numbers work on an old bugger?

Imo000

Have you considered swapping to only an S4 setup? The difference between the S and S4 brakes is huge. It could be a real good bargain to swap to the S4 setup.

justin

I have been thinking about that.

Jim M.

Justin, If you go to S4 front brakes you don't have to upgrade to 17" wheels. If you go with "Big Reds" you need 17" wheels and the spare will no longer fit on the front. The Big caliper P/N's are: GTS Big Blacks 928-351-423-03, LH caliper, 928-351-424-03, RH caliper. 993 TT Big Reds 993-351-425-10, LH caliper, 993-351-426-10, RH caliper. The rotors are 928-351-045-01, LH rotor, solid, 965.351.045.00 rotor, ventilated, LH (cast holes) 322mm, 928-351-046-01, RH rotor, solid, 965.351.046.00 rotor, ventilated, RH (cast holes) 322mm. The GTS and 993TT big reds are the same except location of bleed and crossover tubes; the 911 has the caliper in front of the axle. Both use 44/36mm pistons. The C2 turbo little reds also bolt on, but the piston sizes are larger, which gives more braking force in the rear. Use the GTS or the C2 turbo rotors. You also need 1 pair brake rotor backing plates P/N 928 351 083 04 & 928 351 084 04. Cross-drilled rotors 322mm front 302mm rear. Devek’s Big Red rear caliper is 993TT rear caliper modified to fit the S4. The rear calipers (30mm & 28mm pistons) on the GTS are the same as the 944 turbo’s, 944 S2, 968, 928S4, 928GT, RS America and the later 911 C2/4. All the front-engine cars also use the same size MC with these calipers. The same rear brake package as on the Devek White car, the rear pad is the same size as the front S4 pad and the rotor is 302 x 28 mm (stock rotor, is 299 x 24 mm).

All of this bolts right up to an S4, 87 thru 91. I don't know what you need to do for an OB!

Jim Mayzurk
93 GTS 5-spd

Stan.Shaw@Excell.Net

you either need to swap to S4 spindles or go with the adapter.

Fabio421

This is not true. If you use S4 brakes you cannot use the 993 rotors. You will need to use S4 rotors. If you use GTS brakes you can then use the 993 rotors. No matter which you choose, if your using OB rotors you will need the adapters.

heinrich

Old but good thread. So I have a set of Big Blacks (from a 911) and rotors (965.351.045.00 and 965.351.046.00) from a 94 tt. I assume these would all be direct bolt-ons for S4 -> GTS? (brake lines need to be moved to the opposite side)

Ed Scherer

IIRC, you also should also switch to 10 mm longer bolts (the 80 mm long 900.067.268.02 from the GTS vs. the 70 mm long 900.067.154.02 for the original S4 calipers). That's assuming that the "Big Blacks" you're talking about are the 993TT calipers (993.351.425.10/993.351.426.10).

jthwan22 posted a nice parts summary you might want to review.

SeanR

Justinwho?