tifosiman

In the spirit of Aribop, I'm posting a brake lesson here today.

There always seems to be some sort of confusion regarding the size of and nomenclature of Big Blacks verses S4/951S verses 951/S2/968 front calipers. I ran acrossed this pic the other day courtesy of 968CS.DE and decided to share.



On the right is a standard 968/951/S2 front caliper.

On the left is a 951S/968M030/S4 front caliper.

In the middle is a 928GTS front caliper, commonly known as a "big black" caliper.

Note not only the difference in caliper sizes, but the fact that they take different diameter and thickness rotors.

Also, you can see the difference in the way that they mount to the spindle/knuckle. The standard 968/951/S2 caliper on the right mounts with two bolts in a horizontal arrangment (you can't see the holes). The two larger calipers on the left mount with two bolts in a radial arrangement (you can see the mount holes on the calipers). This is why when going from the 968/951/S2 caliper set up to the larger brakes you need an adapter block or the appropriate spindle/knuckle.

This concludes today's lesson. We should try to do more of these. Even if the information seems repetitive for the old-timers around here, there are a lot of newer folks that would benefit. Plus it would make searches easier if the right terms were used.

NineFourFourNeophyte

thanks for the lesson Tifo,
is the one on the right standard for the na also?
-nffn

Maciek

No, the one on the right is different then the NA.

tifosiman

Correct, the N/A caliper is smaller and is only a floating single piston design. It utilizes a smaller rotor diameter and thickness. Mounting holes are horizontal like the 951/S2/968 calipers, but the hole spacing is different.

Tom R.

too bad they didnt include a picture of a NA caliper. Knowing two of my cars have the puny ones on the right i feel so small and inadequate. It would be interesting to see a 951 caliper next to a NA caliper.

Techno Duck

Suprisingly the weight and size of the two calipers isnt to far off.





Here is a regular 4-piston pad next to the regular n/a calipers...



Also a comparison between the Big Black rotors and regular 951 rotors...

iamgod

mother bish how does my NA even stop with those puny things

marksportcts

I did a brake comparison when I upgraded my 2002 Infiniti Q45 front brakes

http://forums2.freshalloy.com/showthread.php?t=159293



Factory Q45 on top, Porsche 993TT on the middle, Brembo GT on bottom






Brembo GT on the left, 993TT center and Q45 on the right


The 993TT front brakes are the same as the 928GTS. 993TT pad has more surface area than the Brembo pad. Both of the rotors are curved vanes and the 993TT has every other vane split.

strandolph

Does anyone have any idea whether the rotor hats are the same between the big blacks and the regular 951 rotors? I've been wondering whether I can use the aluminum rotor hats (assuming I could even get the right rotors) that Kokeln makes for my regular 951 rotors. I have the Wilwood calipers and I don't want to give up the 15" wheels. But I'd like to get some lighter rotors w/o going drilled.

Steve

aribop

Won't work. The Kokeln hats are made specifically to be used with the 993TT two-piece rotor on the MO30 hubs/spindles to get the correct offset when using Big Blacks/Big Red calipers.

aribop

Yay Tifo!

I need to continue the series...

AznDrgn

We should make an FAQ/Tech sticky and add this to it

aribop

You mean like this...?
https://rennlist.com/forums/forumdis...ysprune=&f=133

AznDrgn

Don't see anything there but I was talking about something like this
http://www.jeepforum.com/forum/showthread.php?t=89273

It's stickied at the top of the forum and for my Jeep I've found it to be a great reference.

944Fest (aka Dan P)

Excellent graphic, Mr T. Would it be safe to say the rear caliper on a Turbo S is the same as the right most caliper in image #1?