Porsche Enthusiasts Club Forum

My name is Ben and I've had my 1985 928S2 now since 2006, and have used it and worked on it off and on ever since. If I had have known about the mechanics of 928's back then I probably wouldn't have bought it... several things wrong with it, but my heart told me I had to have it. It's Metallic black (Montegoschwarz special order) with black leather and red piping (special order), and has pretty much all of the history back to day one when it was a Porsche demonstrator car.

Anyway, the long and short of it was that it had four buckled cup replicas, bad front shocks, a knackered radiator, a rotten exhaust, badly patched rust hole in the sill, fuel tank held in by a strap that was pretty much none existent, an automatic that has the feature of dumping it's fluid onto the garage floor, half removed A/C system and TBF.

Yeah... I should have avoided it, but I didn't know that it had TBF or even that auto 928's suffer from this.

I realised the extent of my TBF problem when changing the sump gasket one day. It wasn't good. A trip to see Paul A in a van, bringing back a good used engine, and we were back in business. I did take it apart, inspect and reseal it though, just to be safe.

Two years ago I finally bought my own house, so my time and money has been eaten up by that, so the 928 hasn't seen much loving until recently. I'm getting married soon, and the bride to be want's to use it as our wedding transport, so my motivation has returned....

I recently picked up a load of OZ Futura wheel components, and built a set of 17x11 ET50 and 17x9.5 ET69. Why so wide? Why not! They fit pretty nicely, and Futuras are one of my all time favourite wheels. At the front, I do get fouling on the inside of the wheel rim to the top wishbone when the car is lifted and the wheels are turned. I am going to fit an extra steering rack stop in the meantime to prevent this, but I want a better solution really.

This brings me onto my question. How much more clearance does the S4 suspension give to the back of the wheel? From what I understand, the upper and lower arms are slightly shorter, and the difference in track is taken up by a larger offset on the hub and steering knuckle. What other benefits does the S4 suspension give? Is it much better than the S2 stuff? I'll be able to use the bigger discs and brembo calipers, so that's one benefit, but I know some people swear by the S2 brakes.
I also realise that the standard ABS rings are not compatible on the S4 suspension to the S2's ABS setup, so i'll have to have some different toothed rings made for the S4 hubs. No biggie there though.

I have tried sourcing the bits I need, and thought I was onto a winner, but the seller is insisting on bank transfer, and doesn't really want to tell me about the condition of the parts or even take a photograph to show they exist. Other sources have proved to only have some of the parts, or want too much money.

Plans for the future? Well I was considering a manual transmission conversion! That's a long way off though.

Sorry about the long first post.

Hi Ben

My brother just had Paul A do precisely what you want to do to his 85 S2...

He had driven my 86 S2 (which already has S4 Suspension/brakes as standard) and wanted brakes/suspension like mine....

Paul A knows exactly which parts you will need, and yes its worth it for the 4 pot brakes alone....

I am suprised you got 9.5 fronts to go on and not rub...

I have 18x10 rears, (for traction for my Nitrous) but only 18x7.5 fronts... on those fronts the tyre size is critical to stop rubbing.... 235`s rub...225`s dont...etc... (important as mine is a daily driver)

Any questions...ask away

All the best Brett

Hi Ben (from another Ben)

I have been down this road because I wanted S4 brakes not because I wanted S4 suspension but you get one with the other anyway. And although it was an enjoyable and rewarding journey it was a very very expensive one.

As I'm sure you are aware - you can't fit S4 brakes to S2 hubs because the mounting points are rotated 90 degrees and a kit is not available directly (unless you retro fit pre S hubs(?) So you have to fit all S4 components (even down to the track rod ends which are also different.)

I looked into buying second hand S4 components at first but was very disappointed by what I found - everything seemed ropy dodgy rusty incomplete and expensive for what it was and it looked like I would just be creating more problems than I would be solving - so in the end I just bit the bullet and bought new with predictable results.



It really depends how long you want this phase of your restoration to take and cost? You could spend years and years sourcing and restoring individual components and end up with a distincly second hand assembly that would still cost a sizable amount or pop down your local OPC tomorrow with a much larger wad of cash and have that factory new feel in no time at all - The choice is yours.

I have tried Paul A a few times over a couple of days, but as of yet there has been no reply. He was my first port of call, naturally.

I'll be doing all of the work myself, so will save a few quid there. I don't mind used as long as it's not knackered... money being tight with the wedding, mortgage etc. I dread to think what all new parts cost, must be a couple of grand at least. But I suppose it does make filtering out all of the worn out rusty junk a lot easier!

Ben, What did you do with your ABS? I have heard about using pre S knuckles/hubs, but that makes it even harder to keep the ABS and doesn't solve that I want the additional suspension clearance that the S4 parts give me.

Brett, where do you have a problem with rubbing, on the inside or outside? My front wheels were originally meant to be 17x8.5 ET56, but I went an inch wider on the inside, effectively making an ET68/69. I used to have a pair of 235's on my 7.5 wide buckled fake cups. I think the offset on those was something silly like 50 though, so it was my own fault that they touched on the wing occasionally. They did have 225's when I first bought the car with no issues though.

With regards to knowing what I need, I think i'm pretty much there. I have heard that I can reuse the old track rods, but have to shorten them by about 1/2". I'd replace them, but they aren't that old. The only thing that I'm confused about is the anti roll bar links. I know they are different, but can't seem to find out if my existing ones will work, or if I need the S4 ones.

Hi Ben

I found a specialist firm in the East Midlands that made and fitted S2 ABS rings to my S4 hubs for just £90. I just supplied them with the technical drawings (which I can give you).

I then spliced the S4 ABS sensors cables to my S2 ABS cables. The system has worked great ever since.

You will need S4 drop links for S4 suspension as S2 ones are a different geometry.

Hi Ben

My problem with rubbing WAS because my offset was 52 and was on the outer wing...with 235s ...225s worked though and I also added a set of GT3 5mm spacers to help stability/tramlining at the front...I am not quite sure WHY the spacers improved the front ends stability as it SHOULD have made it worse, but take my word it improved it a fair amount....lol

All the best Brett

Well I spoke to Paul in the end, and why did I bother trying other places? He confirmed that he had all of the bits available and discussed the drop links. He seems to think that the S2 ones should work in one orientation or another. So in a week or so I'll be paying him a visit to collect. I've had used parts from him before, and they are always in good order.

Ben, The drawing of the rings would be a great help. I was going to put my Solidworks hat on and give them a try on there, but you'll save me the trouble. I'm hoping that we can make something up on the CNC mill at work. The pitch of the teeth may cause trouble though with having a small enough cutter. I'll see anyway.

Brett, That is weird about the spacers. Paul was saying that the S2 suspension is more tolerant of the wheels being out on offset. He reckoned that my 69 offset should work a treat though. The set of wheels I had on before were Folger Karosserie 'Sport Line 18', with an offset of 56 at the front, and they were bad enough at tram lining! Maybe my alignment isn't quite right though because I had it done when I had the buckled cup's originally.