ajmarton

Does anyone have experience with upgrading their early model 928 brakes? 928 Motorsports sells a kit. Here are the details - what do you guys think - a worthy investment or not?

PORSCHE 928 S4 Brake Upgrade Kit


Late-Model Braking Performance for your Early 928!

Application : Porsche 928 78-81 all

Background: Some of the first feedback on the Porsche 928 was that it was under-braked for a car of its weight and performance characteristics. Porsche went through two major re-designs (the "S" brakes, then the S4 brakes) before arriving at this wonderful 4-piston, large-rotor setup.


If you Love your 928, Brake It! Why risk a front-ender that will cripple or possibly total your Porsche when a proven, bolt-on, brake upgrade is available. The difference in braking performance and stopping distances between the early setup and the big S4 brakes is AMAZING.


The Kit: We are going to provide you with EVERYTHING you need to pull your 928 into the garage and drive out with S4 brakes in a couple of hours. Easy bolt-on installation. We use include GENUINE PORSCHE parts, new rotors, new anodized billet brake adapters, new Porsche OEM hardened mounting bolts, new Mintex Street/Sport brake pads, and new Stainless Steel brake lines. The only used parts are the 4-piston genuine Porsche calipers themselves, and they have a 1-year free replacement warranty from our supplier direct to you.



The Bonus: Every brake upgrade kit we sell comes with a complete replacement set of front and rear stainless steel braided brake lines. Braided stainless brake lines will give you the firmest brake pedal you have ever felt - and the piece-of-mind that your flexible brake lines are new, and abbrasion and cut resistant.


The Brake Kit Includes:

2 NEW front brake rotors
2 USED Porsche 4-piston calipers
2 NEW anodized Brake caliper adapters
4 NEW stainles steel braided brake lines
4 NEW Porsche OEM hardened brake mounting bolts
1 NEW set Mintex Street/Sport brake pads

Options:

We can add a matching set of Mintex Street/Sport rear brake pads to your kit for $28.50
You can upgrade from Mintex front pads to Pagid Orange Racing pads for $185.00


Fitment Note: These brakes are bigger - SOME (not all) early "Phone Dial" wheels will not fit over the new 4-piston calipers without rubbing. If this happens, all you need is a pair of 6mm wheel spacers which we carry for $53.00.

Airflite40

dont know how often you hang out here, but 928 motorsports is a trusted vendor, Carl Faussett is a great guy. Is your car a street car or a track car? Many have said that with the right set of pads the early S brakes are fine, but you have the early brakes, which IIRC are the same as 944's. You wouldnt need new spindles, so if you got the cash, I would do it. Make sure you've got clearance with your wheels. If i didnt need new spindles, and I had the cash, I would do it in a heartbeat, but then I would need better wheels to show off my giant brakes.

Pfunde

Go for it, I did and wow......wow, no it can brake !

Ispeed

Yeah, if you have an early car then it's a relatively easy upgrade. You can also add S4 rear calipers and rotors to the rear to do the full upgrade, even though most of your braking is just done at the front.
I added S4 brakes to my friend's '85 euro and it made a huge difference. Big improvement.

Andre Hedrick

My '81 is still in the air because I forgot to detail the conversion list and test if I would need spacers. Also listen to what Carl has to say about this issue too. The bucks I saved by getting the entire set of S4 calipers on ebay and 993 rotors, upgrade mount kit from 928intl, I am burning with airtime on the lift.

Pfunde

I would go for front and rear, I did - and I'm sure the brake balance is better that way !

ajmarton

Thanks guys. The advice was helpful. I will bite the bullet and get the set.

Scott M.

AJ;

Not all 81's are so easy to convert. Later 81's (forget the cut off vin#) will require a change of spindles, lower control arms, etc. Check to make sure yours is the early non-S style. If you have the S setup, you can go two routes: buy early 78-80 spindles and the adapter, or go with S4 spindles and lower control arms (then no adapter is needed).
Upgrading the rear is very easy, just need a thick washer to space the caliper over the new rotor.
While you're there might as well buy a Power bleeder, it's $50 well spent.
Lastly, do a search here for how to 'bed in' the new rotors. Some good reading.

Andre Hedrick

New data point of problems to be solved when doing this upgrade.

If you keep the OEM dust shields, they need to be cut in two places on the from:
The obvious is the the larger caliper first.
The other is to punch a hole next to where your tie rods (pictures to come).

It was really hard to figure out the rub because it only happens in turns but not going straight. Also note these are not the stock tie rods but a set of MOOG steel after market ones. Has anyone else encountered this problem before?

Ad0911

I can buy a set of used 1990 GT brake calipers for around EUR 500. Whta is required to fit these to my 1978 non-S car?

Dave928S

1. An adapter for the calipers to bolt straight to your 78 spindles, together with new bolts (most vendors should have them).
2. 993TT rotors ... which give the correct offset to clear the lower BJ.
3. New flex brake lines.
4. New sensors if you want to fit them (also the connectors are different to the wiring harness .. but you can modify).
5. The early dust shield won't be the right size and so you leave them off or modify later ones (different holes ...2 early /4 late).
Edit: Check your booster size and proportioning valves ... might also be an issue with the larger calipers.

Ad0911

Well, I think I'll just stick to a conversion to "S" brakes in the front. The rears can stay because they are the same. According to the PET, the discs are the same too so I won't have to hange those too. Very cost-effective upgrade from the standard on my non-S car.

Dave928S

That is definitely the most cost effective option to give you quite a leap in brake performance over the front brakes you have now. All you need for the S brakes at the front is the S spindles and dust shields, S calipers, and S discs. Fit good pads, new sensors and flex brake lines, and you should notice a huge improvement.

Ad0911

Thanks Dave, this info helps me a long. The spindles are the hubs where the disc is attached? I happen to have lying around a front suspension of a 928 of unknown year, but with ABS (anti lock brakes). Could these have the correct spindles by any chance? I can't find the number. I also have the the hubs, with the ABS sensors. From your info I guess I don't have to change the hubs so I keep the originals. My question boils down to the spindles. I could post a picture if needed. It would be very convenient if I already have the correct spindles in stock!

Dave928S

ABS was fitted from 86 on with the introduction of the first 32 valve motor. Those spindles (where caliper bolts on) would be to suit the larger 4 piston brake calipers, which were used from that year on with varying piston sizes. You need the S spindles which were the next model from yours through to just before the first 32 valve .. a span of about 4 to 5 years.

Post some photos, if you can, of what you have just to be sure. Also post a photo of the lower ball joint on your car as well .... the early cars have a ball joint housing which might need replacement at the same time.