FredR

JP

If you have 3/4 inch between your rubber and the fender and you put your wheels on a 20mm spacer the clearance will drop to zero mm assuming your measurement is correct.

What offset is your wheel and what width section are you running? My logic suggests you should order a 15mm spacer assuming they do such in this type of fitment.

Rgds

Fred

928gt

Fred - your logic is 100% correct - unless JP means 1.5" in total, hence 0.75" per wheel - which is how H&R markets their spacers, and thus 20mm (0.78") per wheel should be fine. I am using 20mm H&R spacers myself with 9" wide, ET54 wheels and 255 rubber on my '89 GT, although the GT has rolled fenders which the S4 doesn't. And, the wheel offset is going to play a part as well, but that's a moot point if JP's measurements are specific to the new wheels.

Cheers,
Doug

Bertrand Daoust

Just a small precision here, the '91 S4 has stock rolled fenders also. Front and back.

Mine came like that from factory with also D90's. The D90's were an option though. Stock on the GT.

JPTL

You're right Fred. For those with Panamera wheels on their S4 who are wishing to add spacers but don't want to roll their fenders, 15mm would be perfect.
With 20mm installed, I did have zero on the driver's side after settling & under load like you predicted. Pass side had about 3mm. Had this been my GT, I wouldn't have gone to the edge with the spacers since I'm keeping it stock..but since I was prepared to do a mild roll of the fenders on the S4, I went with 20mm.
I ordered the same set that Sean linked to (good price, decent quality and fast shipping).
They bolted right up, although a little snug at the hub-centric shoulders (I might have to kick the wheels the next time I'm removing them).




Here are before and after pics:









At 3mm before settling, I was expecting some rub after settling and under load; which I got.
Since a baseball bat would have been too drastic for the roll that I wanted, I started with a socket extension, then a 5/16 deep socket on the extension; then a 1/2; then 9/16 and so on. I got the roll just how I wanted it. Really not detectable.
I'm happy with the results.

Chris Lockhart

Looks great JP!!

JPTL

Thanks Chris.
If I had to do it over again, I'd opt for the 15mm. Since bringing it out to the max looks good, it required some minor fender rolling and the tire is still really close to the lip. I'm not sure what track extremes will bring about. I guess I'll put some strips of masking tape on the rub areas, take a drive on a bumpy, twisty road and see if the tape stays on...

FredR

JP,

Remember that on these cars you are running on very stiff knicker elastic and things move when under load and especially so on the track when you are pushing it. Sounds as though you are aware of this and anticipating the worst but you do not want to ruin your track day gouging your rubber so do be careful.

I had a similar looking amount of clearance on my GTS when I first fitted 295 rubber on my big 10 inch ET60 rims. I detected rub in fast corners so removed the stock 38mm spacers, threw in some 24mm spacers I had in my kit and fitted open lug nuts to take up the slack as it were - problem solved.

I recently fitted new 285 rubber so I may well go bacl to the 38mm spacers noew that I have an extra 5mm of clearance to play with.

What offset, rim size, rubber width and camber are you running as a matter of interest?

Rgds

Fred

JPTL

My S4 has the LSD option - not sure about the SKE option* though.

The Panamera rears are 18x9 ET 53 with Toyo Proxes 275/35.
Camber is -1.7° at both corners.
I'd think that the neg. camber would draw in the top of the wheels under load, and if the Weissach toes-in the rear wheel under load, I doubt it would be enough to bring out the top rear portion of the wheel enough to rub...I guess we'll see.

*Steif Knicker Elastisch

FredR

JP,

The outside wheel tends to "stand up" more under the greater load as the rubber digs in thus the need for camber to compensate, but under such circumstances you do not have the clearance you have when static. If you have the camber right just calculate how much it moves to bring the tread perpendicular to the tarmac and work out whehter you have sufficent clearance. I reckon you need 5mm clearance to have a fighting chance.

Your rear camber setting is not unreasonable for track work but you may find it too much for the traffic lights derby. I found that to be the case with 295 rubber on the rear so I suspect a measly 275 cover will struggle somewhat at the lights.

Regarding the Weissach rear arm as I understand it prevents lift off oversteer by causing toe-in under such conditions. Mashing the throttle naturally induces toe in thus why we hit the gas when committed. Basically this is why a 928 can beat the snot out of most 911's going into a bend. They have to brake in a sgtraight line whereas the 928 ca brake later and continue braking after the turn in has commenced [trail braking] and thus why I fitted the 35 bar bias valve as opposed to the stock 18 bar item.

Rgds

Fred