tifosiman

Yeah, if you move the caliper anymore outward radially, there is no way this would fit under the 16" wheels. It's tight as it is in there.

pete95zhn

OK, here's my contrbution to this issue. I happened to write an article to Porsche Club Finland Magazine about upgrading 951's brakes. While it's totally worthless to post the whole article here, mainly because it's in finnish......I made an excel sheet about caliper and pad differences.


Type...944t '87...turboS...BR/BB......GT3 '99-...GT3/GT2
Disc.....298x28...304x32...322x32 ...330x34......350x34

Caliper
attachment...A 94mm ....R 130mm.....R 130mm..R 142mm...R 142mm
pistons.........40/36mm...44/36mm... 44/36mm...44/36mm...38/32/28mm
area/cal side.22,73cm2...25.38cm2...25,38cm2...25,38cm2...25,54cm2
pad area......49,7cm2.....67,2cm2.....86,9cm2.....82,6cm2.....125cm2
minimum wheel..16"...........16"............17".............17"...........18"

A= axial, R= radial attachment to spindle

The difference between turboS and BR/BB pads is their height, 51,0mm vs 66mm both are 131,8mm wide. Ferodo has here: http://www.ferodoracing.com/it/download.php?type=8 application tables and drawings with measurement about their products. IMO Diver944's solution is worth thinking. Very cost effective.

CP944T

I currently have the S4/951S caliper/rotor on my '87, with the axial/radial adapters. Can I just add the additional spacer and longer bolts to use with the larger rotors and no other conversion pieces needed?

azmi951

Yes. That is the point of the kit. This is minimal work here and involves no more than the normal caliper and rotor R+R.

DanR

I thought that the caliper also has to be ground a little to clear the rotor? If you look at Marks original thread he also had to do that. Does not seem to be a major deal, just grind away some material and away you go.

333pg333

Nice one Pete. The only thing I'd add here is weight (unsprung) of the extra rotors, although the later monoblock calipers are probably as light or lighter than say the BRs? The key stat is also the the attachment line:
attachment...A 94mm ....R 130mm.....R 130mm..R 142mm...R 142mm
which shows why it's probably too hard to put the last two on later model 951s. I'd love a set of the GT3/2s but they won't fit. Alternatively you can opt for the race version of Brembos or similar PFC, StopTech, Alcon etc but they are very expensive and true overkill for 99% of our cars.

tman

Looks like a pretty nice upgrade for turbo S cars.

pete95zhn

Actually we discussed this same issue over here during this weekend, and one 928-driver ( poor lost soul... ) is developing adapters for 6-piston calipers with 350mm discs, for a GTS. He claims that if there's more than 10mm of adapter required, it can be done. In other words, 330mm disc is too small, but 350 is enough. I haven't yet seen those either live or in pictures. Remains to be seen. The car itself is getting somekindofablower too.

thingo

Why not just change the spindles and use adaptors if you prefer to go six piston?
A lot of people track cars with non M030 spindles so certainly strong enough.And they are a lot better value...

333pg333

That is of course the other way of doing it except doesn't that mean a change of Arm and offset?
Is that how you're doing yours Rod?

thingo

Same offset, same arm,yes my 968 is non M030, I got an extra set of spindles with my Charley Arms anyway.

Iridium

Is anyone selling the spacer and bolt setup as a kit? I don't need anything other than those...

mark kibort

Looks like we have almost 5 guys to get an order together. the machine shop needed at least 5 sets to make it worth his time. The parts turned out pretty nice.

If everyone can confirm by PM, Ill get the ball rolling for the spacers and the bolts and get a price for just those. I think only a couple wanted the discs and pads as well.

Let me know.

mark

mark kibort

Yes, this is the only caveat, but it is about 5 mins per side with a dremel and its only at the edges. Unfortunately, this caliper, that is the same size as the F40/F50 Ferrari caliper, is made for the little sub 12" rotor. and not the 14" found on the F50. so, a little area needs to be radiused.

mk

mark kibort

That has nothing to do with the the pad coverage.

How did you do this? I hope you radiused the calipers and used spacers.

Did you pull the rotors and go back to stock rotors , as the calipers we are talking about using are the stock stuff.

It doesnt matter that the Big red pad is wider. as I mentioned, many of the top systems incorporate the exact same pad as the S4 pad. Namely, the ST40 Stoptech. the inner diameter that doesnt touch, cant be involved in vibration, as its not being touched . You need to mate the pad to the rotor via the spacers so that the entire pad is matched to the rotor. thats where the value of the spacers I will make will provide. they are perfect for a 2mm grind off the edges of the calipers and the pad is perfectly placed on the rotor.

mk