What are the best brakes for an early with 15X6s?

[Brent Seidel]

I would like to keep the original Fuchs wheel, but more stopping power would be nice. What are my options?

[dd74]

Originally Posted by Brent Seidel

I would like to keep the original Fuchs wheel, but more stopping power would be nice. What are my options?

You should address the brakes you now have. With that, try a higher performance brake pad and fresh fluid. Check your brake lines to make sure they're in good shape.

What year is your car? I ask only because 15x6 Fuchs are indicative of an early to middle car upward to about 1977. If that's the case, adapting larger brakes from an SC or Carrera rises in complication as it involves obtaining front struts with 3.5-inch spacing to utilize these brakes. This can get pricey as those struts are fairly expensive, as you'll see via what our Forum Host offers. You'll next need to have an alignment and corner balance after R&R of the struts. In the end, you will be spending quite a bit of $$$.

[Brent Seidel]

The car is a '71. I believe the car originally had the hydropneumatic struts, which it no longer has. Can I tell at a glance whether the front calipers are the larger ones or the stock smaller ones? Are the later SC and Carrera calipers the same as early S? They do all bolt up to the strut with 3.5 spacing, correct?

[Steve@Rennsport]

Brent:

The best thing to do is see if the front calipers are magnetic or not: that tells you if you have "S" brakes or not. The "S" brakes and all later calipers (SC, Carrera, 930 used 3.5" mount spacing.

There are some options for improved brakes once you find out what you currently have.

[chan1408]

Brent - I also have a 71 - an E originally w/ hydropn frt suspn - you should check your front control arms to be sure they are fully boxed, and not the "open bottomed" ones some Hydros were shipped with. This is the box shaped portion of the arm going from the torsion bar rear end to the ball joint. Some were made as a "U" shaped channel for the Hydro, while I believe all for the torsion bar were made as a closed box. If you have the U shaped ones, and are running torsion bars, they'll break at the inner end weld joint on the bottom side. Both of mine did, luckily one completely, on a 25mph stretch 2 miles from home, the other found crack by inspection.

Regards,

Chip

[Brent Seidel]

These look boxed, Eh?

[Brent Seidel]

OK, I tried the magnet test. It stuck. This means they're cast iron which would be the original early brakes, not S or later???

[Bill Verburg]

If they are iron calipers then they are later A w/ 3.5" mounts or M w/ 3" mounts.

If the front and rear pads are the same then they are M, if the front is bigger than the back pads then the front are A, the back are surely M

[TRE Cup]

if you are on a budget and can't change out front struts to the 3.5" mount spacing. You can consider the install of vented rotors (which you may have already) and early BMW 320i or volvo calipers up front. Both bolt on and work with 15" fuchs. The bmw units may need a little shaving with a file on the outer castings. Either will give you more stopping power, larger pads for little expense.
The caveat is that your existing struts are straight and shock inserts in good condition before you spend $ on the calipers and pads.
I think our host may also have a front only caliper upgrade for 3" mount spacing struts

[Brent Seidel]

TRE, Looks like I've got the standard M calipers with vented rotors. I'm interested in your comments about the 320i or Volvo brakes.

If such calipers were installed would I have to change the rotors too? Or are there just more rotor options with these calipers?

And the Volvo brakes would be off of a 240 DL/GL?

There must be a tech article or some reference material available.

Thanks for your help. -Brent

[naparsei]

Most of what you need to know is probably right here: http://www.pelicanparts.com/techarticles/914_BMW_calipers/914_BMW_calipers.htm

This is a pretty common upgrade for 914s.

[ttweed]

Originally Posted by Brent Seidel

There must be a tech article or some reference material available.

Brent-

Before you start down the path of upgrading your calipers and rotors, read this article and this one.

It's not the brakes that stop the car--it's the tires reacting against the road. If you keep the same 6" Fuchs and tires on the car, your original stated goal of getting "more stopping power" will not be achieved simply by putting on bigger calipers and rotors. In fact, you will pay a performance penalty in increased unsprung weight and rotational inertia from bigger brakes. Unless you are tracking the car and experiencing brake fade constantly, I wouldn't even consider bigger brakes a necessity, and I would try every cheaper alternative to controlling heat first (cooling kits, hi-temp fluid and pads, etc.) If you don't like the "feel" of your brakes, there are many other things you can do to change pedal effort, compliance, bite, etc.

Stock Porsche brakes were adequate for any street application in every car they have ever built, IMHO. The best thing you could do to reduce your braking distances is probably 7" rims and bigger, stickier tires, along with a good alignment and corner-balancing.

That's my $0.02,
TT

[jhora]

I agree with Tom....
It seems like every time someone has a brake issue...the solution is bigger brakes....let's see I will fix it....I am going to put some 917 brakes on my 914 that will stop it, etc....
Get your 37 year old braking system back into factory shape and you will not have any issues....refurbish it to the point that it will be like the day it came out of the factory....with today's new brake pad materials and new brake fluids you will be way ahead....then as Tom said good sticky tires....
Rebuild it and have some fun doing it...you will learn a great deal about the car and it will stop better than ever...

John

[Bill Verburg]

Originally Posted by John Hora

I agree with Tom....
It seems like every time someone has a brake issue...the solution is bigger brakes....let's see I will fix it....I am going to put some 917 brakes on my 914 that will stop it, etc....
Get your 37 year old braking system back into factory shape and you will not have any issues....refurbish it to the point that it will be like the day it came out of the factory....with today's new brake pad materials and new brake fluids you will be way ahead....then as Tom said good sticky tires....
Rebuild it and have some fun doing it...you will learn a great deal about the car and it will stop better than ever...

John

while I agree that one should always start w/ a sytem in nominal condition, once the cars start going beyond low 2000# and low 200hp areas the brakes increasingly have difficulty dealing w/ heat during track events. Once the cheaper solutions of cooling, pads and fluid is shown to be inadeqaute then the only thing to do is remove weight and/or use bigger rotors.

[lateapex911]

I agree with Toms points, and Bills! Tom is talking mostly about street applications, where Bill is, I think, commenting on more track day useage.

Question for the experts. What about S front calipers? Increased stiffness resulting in better pedal feel and better heat sinking were the two advantages I was told. Id that true? Would S calipers represent a good middleground?

(rereading this, it appears that his spacing is 3", which precludes the use of S calipers. so, if that is the case, nevermind!, LOL

[RWebb]

Most will claim that the Al S front calipers have DE-creased stiffness. Altho I have driven similar cars with S calipers and Carrera calipers and didn't note any difference (that was not readily explicable based on pads).

"resulting in better pedal feel" Claimed to be opposite as per above; again, not noticed by me.

"and better heat sinking"
- This is mainly ("almost entirely") a function of the rotors and their mass. Al should conduct heat away a little bit better (once it gets past the pads), but I just cannot see that as being a significant effect. Al is used in modern calipers mainly to save wt.

[lateapex911]

Fair enough!

I had understood that the early pot metal calipers were a bit flexible, but I am no expert on the subject!

Just for giggles, may I summarize then?
M claipers..early pot metal, 3" mounts. Smaller pads?
S calipers..early. aluminum, 3.5" mounts, larger pads/
SC calipers...not (?)aluminum, 3.5 " mounts, same size pads as S.(?)

Is that correct?