BIG REDS on '88 Carrera with 16" Fuchs?

[cliyde]

After being told Big Reds will not work under 16" Fuchs, figured I'd post and help to dispel this myth since I'm already running BIG REDS all around on 16's...
simply put, YES, it can be done!!

My front setup: These are genuine 16" Fuchs in 23.3mm offeset (951 Fuchs). This offset provides just enough space for the Fuch petals to clear the caliper.

My rear setup: Genuine 930 Fuchs 16 x9's 15mm offset

The trick here is wheel weights cannot be mounted on the inside on any wheel, Weights mount on the outside lip, period. (que the "ewww" comments from purists). There is virtually little room between the inside wheel barrel and brake caliper, except for possibly a pencil. I have not measured to be precise, but I may at some point.

Finally, there is a small amount of caliper metal shaving at the outer edge, closest to outside of wheel which is necessary to keep from rubbing. I'd liken this similar to a 930 brake install and shave. Other than that, these have been issue free and the stopping power is just incredibly overkill - fun!

Hopefully this helps anyone who was contemplating going this route. Perhaps anyone else that's been down this path will chime in also.

Cheers

[rattlsnak]

Paging Bill Verburg!..

[75 911s]

That's tight! I'm by no means a purist, but I can't get over running wheel weights on the outside of the wheel. Especially given how bad and lazy tire guys are. There would be 16 weights on my rim.

So I have a similar problem with clearance using the Maxilite 911R 7X15 wheel *49ET - The stock rear M calipers on my 75 BARELY clear the wheel with an 18mm spacer. I have to micromanage every time I get a tire mounted (weights go here ONLY) which is kind of a pain.

I do like that you ran 16s as I think they do look more appropriate on an IB era car than 17s.

[Flojo]

about time that StopTech does a plug-and-play 4-piston caliper clearing regular 16s
I mean… so many dudes ask for it, there is a market!

[faverymi]

Can you post the caliper part number.

I know you wrote big reds

Great project. Thank you.

[spuggy]

951 fuchs have more clearance. The pre-ABS N/A 944 used the same fuchs as 911, IIRC.

951 was launched 1986, these didn't exist before then. And the 951 got ABS for 1987 and the offset changed to match - so these were a one-year only part.

On the other hand, almost 50% of 951 production was for the 1986 MY, so they're not as scarce as they might be...

[darrin]

cliyde -- did you change/increase rotor size in conjunction with the caliper swap?

[cliyde]

Don't recall seeing a standard Porsche part # stamped on these anywhere. The wheels come off soon for a track tech so I'll look again.

The calipers installed are Big and they are RED, so that's why I wrote the post. I've learned there were variations with these brakes when introduced on 965 Turbo, 993 C4S / RS vs 993 Turbo. In which case, will the real BIG RED's designation please stand up?

What does the standard 993 caliper look like and what are the technical differences?

Originally Posted by faverymi

Can you post the caliper part number.

I know you wrote big reds

Great project. Thank you.

[cliyde]

Rotors are mix of 930's and 993 I understand from shop that did the upgrade. Going to look for part #'s on the build sheet.

Originally Posted by darrin

cliyde -- did you change/increase rotor size in conjunction with the caliper swap?

[cliyde]

Are these standard 993 calipers (Medium Reds?) Does the moniker BIG red simply entail larger rotors or is there a technical superiority, advantage over one caliper or the other? Asking for a friend.

[Bill Verburg]

I can't tell from the pics whether they are true 'Big Reds' or not


I don't see the rears either, if they use the same pads as the front then they are 1 of the 2 versions of rear 'Big Reds', The 2 versions are 993RS and 993tt, the difference is in the caliper pistons. For 911 use you want the 30/36 993RS versions. If they use the smaller 4 piston caliper then hopefully it's a 993 rear.

'Big Reds use 322x32 f & 322x28 rear rotors, It's a major job to mount the 993 322x28 rear rotors on a 911 most of the time 304x32 front and 309x28 from a 930 are used on 911s

Here's my car w/ true 993RS 'Big Reds'

Front, 322x32 993RS/tt rotor & Big Red caliper



rear, 322x28 993RS Big Red caliper


993RS rear and front, a 993 would be similar to the Big Red rear, differences are pistons and mounting method. The big red front has a fatter chunkier appearance and a lump on the outer face edge



this is a 930 28x309 rear rotor w/ a 993RS big red and 964t rear caliper(small) a 993 rear or 964 f/r would look similar again there are detail differences


on left is a modified 993RS/tt rear rotor and a 993RS/tt front rotor w/ a flat 911 hat


from Left 993tt rear w/ stock axial monts, modified 993RS rear axial mounts machined off and converted to radial mount like the front


994 rear almost a bolt of w/ 930 rotor, 993 rear is similar though w/ detail differences


The key to anything bigger than 930 front is to use either 951 7ET23.3 or 9518ET23.3, these both were designed to provide more room for calipers , they can be differentiated from 911 versions by the countersunk lug nuts as is also used on 9x16 Fuchs,

The 8Et23.3 Fuchs isn't a really happy fit, it can be done but w/ too many restrictions for most peoples taste, for an 8 you really want an ET~27+/-2

[cliyde]

Hi Bill, appreciate all the info. I'm now wondering if these are 993RS then... AWhat do you think? There's 2 difference piston sizes in each caliper.




Cheers

Originally Posted by Bill Verburg

I can't tell from the pics whether they are true 'Big Reds' or not


I don't see the rears either, if they use the same pads as the front then they are 1 of the 2 versions of rear 'Big Reds', The 2 versions are 993RS and 993tt, the difference is in the caliper pistons. For 911 use you want the 30/36 993RS versions. If they use the smaller 4 piston caliper then hopefully it's a 993 rear.

'Big Reds use 322x32 f & 322x28 rear rotors, It's a major job to mount the 993 322x28 rear rotors on a 911 most of the time 304x32 front and 309x28 from a 930 are used on 911s

[Bill Verburg]

Originally Posted by cliyde

Hi Bill, appreciate all the info. I'm now wondering if these are 993RS then... AWhat do you think? There's 2 difference piston sizes in each caliper.




Cheers

It certainly looks like a front 32x322 993RS/tt rotor, at a guess yes, it's a 993RS/tt caliper they all have 36/44 pistons. These are a fairly easy addition to a 911 because the 993RS/tt 32x322 is a 2 piece design, unbolt the 993 hat and bolt on a flat 911 compatible hat

l > r
993RS/tt rear 28x322 modified for 9111 use 993RS/tt 32x322 front w/ 911 style flat hat


front > back
axle sets of [930f/r // 964f/r // 993r // 964t r(all)], [ 993f/993RS/tt r // 964RS/t f ],[ 993RS/tt f // 964 3.6t f]


f > r
stock 993RS r caliper 30/36 pistons(this is the one that a 911 wants in back) stock 993tt r 28/28 pistons


993RS/tt 32x322 rotor w/ stock 993 hat


It's difficult to see the differences between a big red front and a big red rear, the main visual difference is the height of the pad which can best be seen from the side
l > r
993RS/tt rear(big red) 993RS/tt front(big red)


the 993RS rear was also used w/ different configs in 964RS/3.3t front, 926S4 f, 993 f