SB928

I know the conventional wisdom is to just have whatever brake system/calipers that came with your 928 be in tip top shape, but what other Porsche calipers would fit a 1979 Non S/Base 928 whether it needed adapters or not?
I guess the first and cheapest route, aside from completely going through my system, would be to replace with S calipers. After that, what are other Porsche calipers that would fit even if they needed adapters?
I don't feel like I'm going the route of installing Big Blacks, just wanting to know more possible options.
Thanks
Bob

FredR

The most obvious upgrade must be to go for S4 calipers/discs with aftermarket adapters from our key 928 suppliers. The main items can also be obtained at reasonable pricing from someone upgrading to the GTS setup

hlee96

I am also doing this on a '78. Make sure you get the correct front rotors (993) with the hat height offsets that will go with the S4 calipers/adapters. On the rear, all you need are some spacers to space out the calipers appropriately on the rotors.

The Forgotten On

993 calipers fit with front adapters and some washers as spacers for the rears. As stated above, you need 993 front rotors and 928 rear rotors for this to work.

They are the later piston design so parts are easier to get. The front caliper piston sizes are the same for the S4 but the rear pistons are 20% larger.

I use them on my 81 and they are fantastic. They are also occasionally less expensive than 928 calipers.

hlee96

I am also doing this on a '78. Make sure you get the correct front rotors (993) with the hat height offsets that will go with the S4 calipers/adapters. On the rear, all you need are some spacers to space out the calipers appropriately on the rotors.

Do a google search: "Porsche 928 S4 calipers on OB rennlist" and you will get almost all the info that you need.

good luck!
-Hoi

SB928

Thanks guys for the advice. What is confusing for me a little, is all the numerical designations Porsche assigned to their cars after awhile. I've had in my past 914, 911, 912, 912E, and 944, but when they started all the 993, 996, 997 numbers, they lost me, mostly because I never had such a newer car.

What would help is which calipers fit and, am I assuming correctly that all, or any, will need adapters? Again, I'm assuming all 928 calipers will fit, but am I only looking for 993 calipers or are their other options?

I see a lot of Boxster, Cayenne, Cayman calipers on eBay but have no idea if someone makes adapters for them and if they would work.

Bob
1979 928 Euro/RoW hopefully back on the road here in CA. soon.

hlee96

Many Rennlisters have done this upgrade, so spend a little of time doing the search and there are plenty of info here. S4 brakes are more than enough for the speed/weight of the OB cars.

Here was a thread that I started and plenty here helped, so hopefully, this will help your cause:
https://rennlist.com/forums/928-foru...s4-brakes.html

-Hoi

Ad0911

I did the "S" upgrade on the fronts because the rears are the same for S and non-S. Don't know if this will result in better braking but someone said that the S brakes are everything you need. I hope they are. Car isn't running yet.

jheis

Bob:
I have a pair of good "S" calipers off of my '82 from when I did the S4 conversion if you're interested. I'm up in Santa Rosa
https://sfbay.craigslist.org/nby/pts...549387511.html

James

SB928

James, I was about to email you about your ad about an hour ago, but thought I'd scour the internet for other calipers or someone I thought would likely ship them to me.
I have no time to get up to Santa Rosa, so what would total for shipping and the calipers be?
Thanks
Bob

shipping to San Bruno, 94066 (Home of the YouTube shooting, about 5mins for my house)

The Forgotten On

Oh yeah, early Audi S8 4 piston calipers are the same as GTS calipers but a heck of a lot cheaper if you can find them.

Darklands

This Audi S8 from 2001 or the first ones from mid nineties? I think they look bigger with 360 mm Discs.

SB928

James/jheis, Thanks for the offer, but after phoning the guys at 928Intn'l, I may go for the S4 calipers after I get my car back of the road. I rebuilt the existing calipers on the car (Non S) and new rotors and Hawk Pads. May like it as is, you never know.

Bob

kiwiokie

Ad0911

You need the so-called spindles from an "S" car. That is the part the calipee is bolted on and it has the stub axle part where the wheelbearings are on. And off course the dust covers, discs, etc. Overhaul the calipers (really easy job if pistons and barrels not corroded inside). The set with seals is really cheap because these calipers were used for many cars (BMW, Fiat, etc). Buy the complete set from local car parts shop. Amaze yourself about the clever design of the caliper. Buy Zimmerman S discs. The Best! Treat yourself to new lower ball joints if you still have the aluminium ones. Buy new flex lines. Readily available. Buy new bolts to mount the calipers. Of course a new wheel bearing set or 2. New bleeding valves. Dust covers are in the set of seals. The part that carries the disc (don't know the english word for that) can be reused but give it a thorough cleanup..
Good luck
I might have a picture of this setup. I'll look around for it.