Go-carter

Silly question - but how do I know if I have aluminium lower ball joints? Picture?

Dave928S

As I said in my earlier post, I don't agree that the S brakes are adequate ... alright for shopping cart driving, but if you plan on having a real go they are not up to the job ...IMO. The discs you need for brembo S4 calipers don't cost any more than the S4 discs. You're right that they won't fit inside phone dials ..... but I see manhole covers in the OP's avatar .. and they fit inside those just as they do on an S4.

Edit: I'm basing my brake comments on a 4.7 euro motor, so I guess to be accurate, S brakes may be/will be adequate on the less powerful early US motor.

Not a silly question at all. The aluminium ball joints are thicker and have a smoother external side profile than the steel ones, which you can compare to in the second photo. A magnet can be used to tell the difference also, but the thickness and shape as shown are a dead giveaway. The studs protrude through the steel ball joints further, and therefore you need to trim the studs, or use the later mounts with the shorter studs.

dr bob

Magnet is a simple test for aluminum ball-joint carriers.

jwillman

What are the differences in S versus non-S brakes?

Thanks

Podguy

The early brakes are the same for front and rear. I find with the 78 brakes I was getting serious fade coming off the local mountain. This is dangerous since as they fade you can end up cascading down the hill with no brakes. The emergency brake will not do you much good in this case.

I find the S brakes a great up grade. You can tell the difference immediately in the first stop. Just a touch brakes and the car comes to a stop. Sometimes a little too soon. I have driven them under hard driving with the heavier 32 Valve engine and never sensed any fade. Now maybe if you are racing you might need more. But for any hard street driving the S brakes are a very cost effective upgrade for the older 928. If you go the Bembo upgrade you really should swap out the front suspension. There is a difference in the S4 brakes. The ones to get are the 1989 up. The upgrade just for the front will cost you $500+ but you should go the whole suspension and this will run $1000-1200 just for the used parts. Then you will need to so some wiring adapting.

I am not sure the S4 suspension gives you much of an advanage. For about $150 you can get S spindles, hubs, disks, calipers and possible the shock adjusters. The rear brakes are the same on the S so you only need to work on the front. Other than cleaning the upgrade is about a three hour job.

GlenL

To follow-up on Dan's response...

The primary difference is pad size. The S brakes are still single-piston like the early brakes.

I have tracked my Euro with the stock S brakes for years. I had fade once when the pads were very thin. Otherwise they have done very well. To get more grip I've used a few brake pads and now use Hawk Blue pads. The car has great stopping power and I brake very aggressively with total confidence. My point being that the S system is really good and I've never felt the need to upgrade just get more aggressive pads. My only complaint is cosmetic now that I've gotten big, open Cayman wheels for my car.

BTW - the rear brakes are identical on all 928s up until the '86.5 switch to S4 multi-piston calipers.

928mac

I think something is wrong with my computer.
It always gets stuck on Dave Tas post

Dave928S

It's probably the same problem I have sometimes Brad ....