993_Pilot

Are the front calipers the same and/or interchangeable? I have been told they were, but I am not sure how reliable my source was. I have also done a search, but didn't find anything and I don't have a source for 944 part numbers. Thanks.

chris walrod

I havent seen a 944 radial mount caliper as of yet, so I would venture to guess that -no- they are not interchangeable. 928 fronts, yes.

Red rooster

Pretty sure that the late 944T has the same caliper as a 993 . Big Reds run a 322mm rotor with a slightly taller pad - width is the same .
You can fit 9 ? mm spacers under the 993 calipers and run 322mm rotors .
That gives 95% Big Red brakes for a lot less money !
17 inch rims are necessary for 322 rotors.

All the best

Geoff

cobalt

The 944 turbo and 944 S2 ran the same brakes which are smaller unless you had the M030 package or a turbo S. The turbo S ran the medium S4 brakes used on the 928 S4's and GT's unlike the Big Blacks which were the same as the Big reds that run on the 928GTS, 94 turbo 3.6 and 993TT's. Although the big Blacks were trailing edge vs leading.

The difference is size. The medium S4's are slightly smaller using a 48mm x 132mm pad vs the big reds which were larger and ran a 58mm x 132mm pad. BTW the Medium S4's were also used on the 993C2 front and were similar to the 993TT rears but were radially mounted vs axially. Whether the calipers are the same, you would need to check part numbers.

IIRC the 944T and S2 ran similar sized calipers and pads as the 964 which are 44mm x 98mm front and rear.

993_Pilot

It is now about as clear as mud! But seriously, thanks for all the replies. I don't really need bigger calipers as I don't do track days . . . yet, but I keep seeing 928 and 944 Turbo calipers come up on eBay and sell for cheap. Very Tempting. When "Big Reds" for a 993 come up, they sell for big $$. I guess that I will have to rely on part numbers and/or do some hands on research. Anybody know where to find the part numbers for the 928 & 944 Turbo calipers?

cobalt

Sorry, not always easy to clarify these things. In plain English upgrading to big reds in the front gains you little to nothing over stock 993C2 calipers. Unless you race the stock brakes are adequate and you would be better off changing pad compound than spending the money on Big reds. It is really a more cosmetic change for most and adds additional unsprung weight. Like I said pad size is almost identical and all you gain is 10mm (.394") in width which allows you to use the full face of a 322mm x 32mm rotor vs a 304mm x 32mm.

What stops the car is not so much the brake size as much the clamping force, tire contact patch along with brake pad and rubber compounds. So the only real gain obtained by the larger rotor and pad is better heat dissipation. Both your stock calipers and the Big reds use 44/36 piston sizes and will both clamp with the same force.

If you buy 944Turbo S or M030 calipers you would be buying the same medium S4 Brembos you already have. If you buy stock 951 or S2 calipers you will be getting smaller calipers similar in size to the rears on your car.

I don't know if this helps, however, If you like the looks of the big reds paint yours red and you can purchase decals to replace the Porsche lettering and change your pad compound.

Maybe this site might help.

http://www.pelicanparts.com/MotorCity/wmv/brakes.htm

Good Luck

Garth S

Anthony,
Always good data Perhaps you could comment: in the Pelican reference, the axial mount rear calipers referred to as S4 ( top table) are perhaps better termed 'rear big reds'. Yes, they use the 928 S4 front pad, but are an identical size frame to the front 'big red' .... both of which are larger than 928 S4 calipers.

Question - the big reds fit 322x32/28mm rotors fr/rear respectively: can these same calipers be fitted to the normal 993 C2/928 S4 304x32/28mm rotors??
I have a spare set of big reds .. and am thinking of project possibilities

Jeff, sorry for the extra 'mud' - but it may help to clarify your question.

cobalt

I have never tried it but have been told and would assume the answer is no. The larger wider pad uses the entire face of the 322mm rotor so if you reduce the rotor dia by .78 inches or .39 per radius I would assume the pad would not fit the face since that is about the incremental size difference of the pad.

I do know you can use the larger rotor with the S4 caliper, as does the 91-92 964 turbo although when buying rotors make sure you buy the '94 turbo rotor part number 965.351.045(046).00 instead of the 91-92 rotor part number 965.351.043(044).00. Both are 322mm x 32 cross drilled but the 94's have additional cooling and are usually cheaper. You can also use the 928 GTS rotor which is non cross drilled Part # 928.351.045(046).00 also 322mm x 32mm.

Good luck

Red rooster

Garth,
The Big Red pad is taller than 993 , width is the same.The benifit of Big Reds is the 322 rotor + whole rotor face used. If you try Big Reds on your 308 rotor the pad will overhang top and bottom !
Sorry to keep on about this but if you space your 993 calipers up by around 9mm you can use 322 rotors. The only difference then, to Big Reds is that the bottom area of the rotor isnt used. Big Deal !!

The RS uses a 40bar pressure limiter which is the same as your 993 ?

For very serious brakes the 996 GT3 monoblocks are far superior to Big Reds
and are the way to go for track use.

Good luck

Geoff

cobalt

My error, Based on my business when dimensioning parts we always consider the longer section length and the shorter width vs height and width which is what you are using. But as said the extra 10mm will overhang.

The GT3 brakes will dissipate heat better but don't you need custom made 18's or19" wheels to fit? If you are going to go through that much trouble why not go with the Brembo 8 piston F1 brakes.

Red rooster

Anthony,

Yes , maybe the GT3 brakes are not the best example ! You also have to go back to 964 hubs to accomodate the support bracket !

The less extreme monobloc brembos are really good and such low cost .

All the best

Geoff

993_Pilot

Again, Thanks to everyone for the replies. This is more a mental exercise for me at this point, because as I said before, I don't really need them. I am always amazed by the depth of knowledge on this forum and I am always trying to soak up as much as possible. Maybe, one day when I am a bit wiser, I can pass some of the knowledge on.

NineMeister

Sorry to have to correct you Cobalt, but there is are slight differences in these calipers. The 944Turbo SE (M030) used the same front caliper as the 1986 928S2 and (from memory) it has 44/32 pistons whereas the 928S4 & GT and the 993 use the 44/36 that you state. If you can get hold of them, the 964RS and 965 turbo 3.3 use a near identical 44/36 caliper that has a 9mm spacer cast into the body to allow them to be used with a 322mm disc.

As always, if you are exchanging calipers from car to car, be sure to get the direction of the caliper correct which may need the cross-tube and the bleed nipples exchanged on the ends.

Talk about ****.......

cobalt

Interesting, and hate to be even more ****, however the M030 944S2 and 944 turbo S fronts do use the 36/44mm piston sizes with 132mm x 48mm pad and 304/32mm rotor. The stock calipers use a 36/40mm pistons with the smaller 98mm pad similar to the original 930 turbo. I have rebuilt these before and can assure you they are similar to the brakes used on the 928S4 not the S2.

If you check the rebuild kits available for these calipers it will verify this. The kit I used said it was good for the M030 944S2/951S and 928 S4 caliper. Usually they sell the 44mm alone and it requires the 951 351 919 01 part which is for the 36mm piston.

There are a lot of variations on some of these calipers that can be similar and it does get confusing.

wjk_glynn

I believe "Cobalt" is correct.

The 928 S4 front brake calipers with the 44/36 pistons were used on the following:

'87-'88 951 w/M030
'88 951S
'89 951
'89-'91 944S2 w/M030
'92-'95 968 w/M030

I'm not familar with the 944 Turbo SE sold in the UK after 951 sales stopped here in the US, but I believe it retained the same front brake calipers as the '89 951 until production ceased at MY 1991.

For a detailed description of the parts (including part numbers) used in the front brakes of a 968 w/M030, see http://www.weissach.net/968_M030-Opt...ml#FrontBrakes

Karl.