CALLED TO THE BAR
If your Porsche could be sold new without a rear anti-roll bar, does it need one now? Chris Horton is not convinced, but having acquired one for the 924S he thought he might as well give it a try
Only once in my life have I had the pleasure of choosing the precise specification of a brand-new car – and that, as a company vehicle, within various budgetary and even hierarchical constraints. So I have always been mildly curious about why all the many others I have bought with my own money came to have the optional extras with which they were equipped. Or in certain cases not equipped.
Why, for instance, did the man – or woman – who first purchased my old red 924S new in 1985 decide that they could do without powerassisted steering? And why on earth did Porsche ever imagine that it was acceptable to sell the thing without it in the first place? As I have observed before in these pages, the car was virtually undriveable at parking speed until I installed the power rack, plus the pump and associated pipework, from a donor vehicle. Was that first owner a champion bodybuilder? Or did they simply not have a test-drive before signing on the dotted line? Surely they could have afforded it?
My current Stone Grey ‘S’ is in that respect only slightly less baffling. It certainly has that all-important power steering, together with electric and heated door mirrors (both features long since defunct), electric windows, headlamp washers (ditto), rear wiper (ditto again…) and sunroof. But bizarrely – and this is meant to be a sports car, let’s not forget – no rear anti-roll bar. I would be the first to admit that these devices are not necessarily of much practical use – I seem to remember that for some months I drove the red car minus its front ARB, and even did a trackday, without noticing the slightest difference – but surely this of all ‘add-ons’ is the kind of device you would provide as a matter of course. (But then back in the mid-1980s, I suppose, Porsche needed all the income it could possibly generate. It’s a wonder it didn’t charge extra for seats and wheels.)
So I can’t say that I have ever felt the absence of said ARB to be a great practical loss. A sports car the 924S may be, but out on the public highway, where the pot-holes are becoming deep enough to swallow medium-sized animals, and ‘A’-road speed limits are reducing all the time, it is largely an irrelevance. An affectation, even, like so many other go-faster devices. I am more interested in good brakes, accurate steering, and the relatively soft springs from which, in very broad terms, derives the wheels’ ability to follow the appalling surface more closely, and thus to grip more securely. (And to provide the necessary ride comfort. More on this in a future how-to.) Even so, having acquired from a now long-forgotten source both a secondhand anti-roll bar and the various items of mounting hardware, I thought I might just as well fit them. Hope springs eternal...
Actually, it would be more accurate to say ‘to continue to fit them’. The two ‘U’-shaped brackets for the mounting bushes I had installed perhaps a couple of years ago, when I had the car up on a lift – in part just to find a home for them so that they didn’t get lost. And even today, with some confusion remaining about the precise internal diameter of the bushes that I need (see below), the ARB itself remains to be added. But what you might call the hard work – fitting the mounting pins on the suspension arms for the drop-links – is done and dusted (considerably more easily than I had anticipated, in fact), and I should in due course be able to fit the bar itself with the vehicle raised on a couple of axle-stands on my driveway.
‘More easily than I anticipated’? Amazingly, yes. The M10-threaded pin for each drop-link is an integral part of the camber adjuster for the rear suspension, which passes through first the vertical ‘blade’ attached to the transverse torsion-bar road spring and then the hub carrier. That outer end has an M12 thread. It was a safe bet that the original items, each minus the necessary inner pin, had lain undisturbed since the car was assembled, back in autumn 1985. And an even safer one that, given a combination of steel and light-alloy parts routinely bathed in water and mud these past 34 years, they were going to be firmly seized in position. It was that, and the suspicion that I would end up also having to release the hub carriers’ other two fixings (requiring the suspension geometry to be reset) that had previously deterred me from having a go at the job at
home, and so when the chance came to get the car on one of the two-post lifts over at BS Motorsport I naturally jumped at it.
First step, with the rear wheels off for improved access, was to spray everything in sight with Würth’s excellent Rost-off Blue Ice penetrating spray, and then, once that had had a few minutes to soak in through the accumulated rust and dirt, to undo the 19mm Nyloc nut on the outer end of each original pin. More Rost-off, screw the nut back on just a few turns, and then hit it hard with a large and heavy copper-faced hammer. (I am unlikely to be needing the old pins again, but there’s no point in damaging the threads if you can possibly avoid it.) Predictably, this did little more than vibrate loose the large washer behind the nut, previously embedded in the corrosion, but that allowed me to get more Rost-off actually into the hole through the hub carrier and the spring blade, and further vigorous hammer blows quickly produced that subtle but always reassuring change of note that tells you when something like this has finally started moving.
Working from the other side of the spring blade, I used a small screwdriver to dig out as much corrosion and dirt as possible from the now exposed slot in the steel plate. A generous dab of Würth anti-seize paste on the new pin/adjuster, and it slid home perfectly, rotating nicely until the eccentric section was in the correct position. Still more grease on the outer end of the pin, together with the washer and the Nyloc, and then tighten them until the large hexagon on the inside just begins to be pulled up against the steel blade. This will enable you to rotate it to its natural position without the risk of damaging that eccentric shoulder – or the corresponding areas of the blade and the hub carrier, of course – as you fully tighten the Nyloc nut. You will need a 27mm spanner, ideally of the ring type, to counter-hold the pin.
Same procedure on the other side, slide on the drop-links (in part just to get them out of the way again) and secure them with new Nylocs, and the job’s done. Ideally, of course, I would have fitted the anti-roll bar there and then, but neither the original Porsche nor the after-market Powerflex bushes I seem to have ended up with have the required internal diameter for the nominally 16mm bar, which some quick on-line research suggests must have come from a late-model 944. (And I still can’t remember where this particular one originated. The other diameters available for this range of cars were 14mm, 18mm and, for those with the sport-oriented M030 suspension option, 20mm.) More expense, then, which is a bit of a nuisance, but better that than wasting time and energy trying to compress the essentially incompressible.
Besides, I am going to have plenty of other things under the back of the car to start spending money on. The outer sheath of the handbrake cable is disintegrating, where it emerges from the right-hand side of the floorpan, and unsurprisingly the fuel supply and return lines are looking increasingly unlikely to pass the next MOT test at the end of this year. Those of you with long memories might recall that this was a job I had done for me on my old red car, using flexible pipework in order to avoid having to remove the entire rear suspension crossmember. That’s a tempting option here, as well, but given all the other issues – including a suspect fuel tank, repair or replacement of which is going to mean removing the transmission, and the corroded lines into and out of the fuel filter, I think I might just bite the bullet and strip out the entire rear end. It should all make for a worthwhile how-to story, anyway.