I have recently fitted 16" Carlsson Super Aeros (chrome rim and dark grey inset) with 50/205/16 tyres to my 1990 900 S Aero but the rear wheel arches are rubbing. ANy ideas on how to prevent this???
I had the same problem. I know some people sayto extend the bumpstops, and if it works for them that's fine, but it didn't work for me. If you do extend them, replace the existing screw with a longer one and pack some more washers on the end. The drawback is that bumpstops drop off on a regular basis anyway, so are probably not going to help much in the long term. And I don't recommend just ignoring the rub, as simultaneous rear punctures would not be conducive to good handling.
I got rub with 205/50/16 Super Aeros with Dunlop SP Sport 9000 tyres. What I did was change the rear suspension. It had a saggy ar5e anyway like most C900s after 14 years, so I bought Sachs Advantage sports dampers from PFS and Ventura heavy duty turbo springs from Eurocarparts. I live in a very rural area and drive on farm tracks a lot so I wanted it to be fairly rugged. The ride is very good - sharper handling, perfectly comfortable on long journeys and no more rub.
I know Garry did a write-up on this over on 900 Aero and if you do a search on here you'll find several posts on it, most of them from me .
Tire size is critical on this swap; nothing taller than a 205/50R16 or you'll have problems. Even this size will give you some rub on the rears. You should add a bump stop from a convertible which is a little longer and will help quite a bit. The better route is to run 45 series tires for a little extra room. If you decide to add lower springs, do plenty of planning and be very careful or you'll have alot of money in a car that won't be much fun to drive because of the rubbing and bottoming out.
Another solution is using some Rear Spring Spacers like these from SAS in the US:
I've searched on this in the past, with mixed results. Quite a few people seem to think that the extended bump stop is a very rare breed indeed - quite possibly it does not actually exist at all. Some say convertibles had them, but others say not. If you can't find anything on extended ones, just use your regular bump stops with some longer screws. If you need new ones, you can get them from PFS . I ended up using the old ones and getting longer screws from a shop that fixes lawnmowers. The problem I had was that I got one bump stop off alright but the other was very corroded. In undoing it the screw snapped leaving the head in there. The local garage got it out and I fitted the new screw into the old bump stop but 2 days later I looked under the car and it was missing. I've not bothered with it since - I've not had tyre rub and I pass MOT's without any trouble just having one bump stop. Although the other has probably fallen off by now, so maybe I don't have any.
well I've no idea how this affects anything anyone else has said but my 40,000 mile convertible wore 205's on 16's and didn't rub unless it was on full load. What I guess this means is that the low-mileage springs on that car kept the ar5e in the air enough to stop rub during every-day use. That fact that it might rub when the car was full indicates that it probably wasn't related to bump-stops and only the fact that the springs were good.
Hey Jez if you still have your old springs then you could measure the un-loaded length and tell us if they were worn-out. This is the Bentley test procedure and they have a table of measurements to reference.
Unfortunately I don't have them any more, but they were definitely worn out. You could see it from the stance of the car; the heavy duty springs I've now got are the same length as the stock turbo springs. Before I could only fit 2 fingers between tyre and wheel arch - I can now fit 3 and a bit. The car actually looks level when viewed from the side.
spax adjustable shocks
ventura 40mm lowered springs
mad aux springs sent to me by lars
the mad springs sit on an plate that is adjustable from underneath the trailing arm
the set up works very well on my car as i was bottoming out with the kids in the back , not any more
the springs are set at halfway just now and craig can comment on the setup as well as he has driven the car
Sam, you can relocate the rear axle forward 10mm to prevent the rear tires from rubbing. What you need to do is cut the trailing links and lengthen them by 10mm. The way I did mine was to take a link from a parts car and cut two 10mm pieces. I then cut each of my links and welded the pieces in at the cut from the spare link to increase their length. Next you remove the pivot from the front of the lower suspension and reverse their orientation and lengthen the opening for the bolts about 0.015". This will give you a total of 0.025" from reversing plus the 0.015" for a total of
0.040" or 10mm.