Front brake question.

[em78911]

I have a 1978 SC with Bilstein front shocks all stock narrow body. I have 928 S4 big black front calipers. Who has a place or know the parts list to get these to bolt straight up and the correct rotor and hat combo for this car? I have searched but to be honest it simply too much information on the topic. does any one have this set up and if so where and what parts ( part #'s ) did you use or buy?

Thanks so MUCH in advance.

- Bill V thanks for the chat about the 993 TT calipers I have decided to not go that big. simply too much brake for the cars setup.

- Eric

[Dmitry at Pelican Parts]

Hello - if our members don't get you the part #s or info, feel free to give us a call at 888-280-7799 and one of our Porsche part specialists should be able to help get you sorted.

[darrin]

found this thread -- 928 s4 calipers?

That said, what issue are you having with your stock setup? What are you trying to improve on?

[em78911]

Originally Posted by Dmitry at Pelican Parts

Hello - if our members don't get you the part #s or info, feel free to give us a call at 888-280-7799 and one of our Porsche part specialists should be able to help get you sorted.

Thanks DMITRY,
Will do.

[em78911]

Originally Posted by darrin

found this thread -- 928 s4 calipers?

That said, what issue are you having with your stock setup? What are you trying to improve on?

Hi Darren,
Not trying to improve anything really. I do not have any brakes on the car. I don't have the stock set up either. I figure if I am going to have to purchase brakes I am not going to replace them with the stock set up, I will go with a set up more suited for track use which is where she is headed.
so just trying to get brakes on the car actually.... just reaching out to anyone on here that has this set up that can cut my trail and error time in half is all.

Thanks.
Eric

[darrin]

gotchya -- looks like the thread I linked to gives you some GOOD direction/detail. That said, it doesn't seem to touch too much on what to use for a master cylinder or rear brake options that will provide appropriate bias/proportioning.

[em78911]

Originally Posted by darrin

gotchya -- looks like the thread I linked to gives you some GOOD direction/detail. That said, it doesn't seem to touch too much on what to use for a master cylinder or rear brake options that will provide appropriate bias/proportioning.

That was a solid link.. thanks! I have a larger Turbo MC..I have 996/Boxster S rear caliper set up already good to go. The Front is the hurdle at this point. Thanks for link!

[Bill Verburg]

Originally Posted by em78911

That was a solid link.. thanks! I have a larger Turbo MC..I have 996/Boxster S rear caliper set up already good to go. The Front is the hurdle at this point. Thanks for link!

The next hurdle will be the rear, the Boxster S in back will not be enough to efficiently balance the fronts

928/993 fronts on 32x304 rotors generate ~2306+/- NM of torque @70bar line pressure, +/- is dependent on pad specifics

Boxster S on 24x299 rotors generate ~1139+/- NM of torque @70bar line pressure, +/- is dependent on pad specifics

That makes for a ratio of 2.02, not particularly dangerous but prone to front lockup and not efficiently using the entire brake system

you want closer to 1.5

I'd want 993 rear on 3.2 Carrera 24x290 rotors generate ~13
39+/- NM of torque @70bar line pressure, +/- is dependent on pad specifics
ratio ~1.7

or using 996 24x299 , ratio ~1.659

[ChrisBennet]

I have "928S4" front brakes (really 993 front) and 930 rear and I've been happy with that setup. I removed the Carrera proportioning valve and went to the larger master cyclinder. I've done a lot of track days and it has been really easy on rotors and pretty good on pads.

[KTL]

I also have used 928S4/993 front calipers with the Wilwood HD 12.19"x1.25" (309x32mm) rotor and "custom" hat (can get the hat from rebelracingproducts.com) along with 930 rear calipers, 930 rear rotors and the 930 master cylinder. The brake balance was OK but I could still tell that it was a bit front biased. When I switched to the 993 rear calipers with 30mm and 34mm pistons, it was a great improvement.

Keep in mind that you'll need to investigate wheel fitment when you go with the larger brakes. Original Fuchs are great wheels but they don't afford much clearance when the brakes get slightly larger.

[em78911]

Originally Posted by ChrisBennet

I have "928S4" front brakes (really 993 front) and 930 rear and I've been happy with that setup. I removed the Carrera proportioning valve and went to the larger master cyclinder. I've done a lot of track days and it has been really easy on rotors and pretty good on pads.

What hat and rotors are you going with for front?

[ChrisBennet]

Originally Posted by em78911

What hat and rotors are you going with for front?

• I started out with the floating rotor hats from VCI and their Coleman rotors. (930 rotors)
  
• The Coleman rotors didn't last well at all.
  
• Then I got factory/Zimmerman front rotors and those wore like iron. I only replaced them when someone tried to turn them and wrecked them so I don't know how long they would have eventually lasted.
  
• I replaced them with more Zimmerman rotors. I don't think I ran those on the track.
  
• Then I switched to a non-floating setup from VCI to address the noise issue. *

* I am not convinced that the noise issue wasn't fixable with the floating rotors but the non-floating rotors didn't squeal like the floating ones. I didn't care about the "clop-clop" the floating rotors made (that was kinda cool) but the squeal they made was unbelievably loud. Scare horses in their horse trailer loud.
Like louder than dump-truck-brakes-loud. So loud that I didn't have to watch for my co-driver to come around the track - I would hear him before I could see him, look up from my book, click the stopwatch and go back to reading. [1]

[1] Oh yeah, in case I didn't mention it, they were loud.

[KTL]

Get the 8 hole hats from Rebel Racing. They can also provide suitable quality nuts and bolts to fasten the hats to the rotor.

A great rotor we used for years is the Wilwood 12.19x1.25 I mentioned above. The Rebel hats fit it very well. You can get the rotor in HD (plain face) or GT (slotted). HD is fine and I don't think the GT is really worth the extra $

Wilwood Disc Brakes - Rotor No: 160-11835
Wilwood Disc Brakes - Rotor No: 160-11839

Note that these rotors are directionally vaned. So you have to buy a left and a right

[bkreigsr]

Vehicle Craft Inc."VCI" Hi-Performance Brake Upgrades For Porsche Cars

I have bought from, and used, Doug's shop for numerous pieces and services.
Nothing but the best.

Bill K

[KTL]

^^^ I just sent him a set of small Brembo calipers this week to do the conversion on a set of front calipers

911 Brake Upgrades using 964/944T calipers

[em78911]

Originally Posted by KTL

Get the 8 hole hats from Rebel Racing. They can also provide suitable quality nuts and bolts to fasten the hats to the rotor.

A great rotor we used for years is the Wilwood 12.19x1.25 I mentioned above. The Rebel hats fit it very well. You can get the rotor in HD (plain face) or GT (slotted). HD is fine and I don't think the GT is really worth the extra $

Wilwood Disc Brakes - Rotor No: 160-11835
Wilwood Disc Brakes - Rotor No: 160-11839

Note that these rotors are directionally vaned. So you have to buy a left and a right

THANKS!!.. awesome so these will work for the big black ( 928 S4 ) style caliper correct

[KTL]

Correct. They are a close fit and the pads have a tiny bit of overhang out the bottom that is inconsequential. Check out this ad for a set of fronts that I foolishly sold from my racecar, because I can never leave well enough alone and continue to fiddle with things

"993" Front Brake Kit

Note that the parts in my front brake setup were a mix and match of things. I had some adapter blocks from some Big Reds, a set of Big Black (964 Turbo) calipers and some adapter hats I got from a fella here on the forums. So my collection of parts wasn't a fully matched set and it still worked fine. Don't forget you'll also have to bend some brake lines to connect the caliper to the flex hose.

You can easily make your setup work nicely with the Rebel hats, some suitable adapter blocks (Patrick MS, Stomski are two vendors I can think of off the top of my head) and the 993 or 928 S4 front calipers.

The real Big Black sit a bit taller than the more common 993 or 928S4 caliper and that's why I had some pad overhang on the top of the rotor. The telltale sign is the extended boss/foot under the caliper as you can see in this picture