993 tyres catching the arches, geometry?

[bubster]

Hi, can anyone help?

I've just fitted some wheels to my 993, see pic, and they catch slightly when accelerating hard and cornering on the rear! The car is lowered, is there a recommended set up to increase negative camber someone could recommend as I don't feel like taking an angle grinder to my arches!




Any ideas?

[clubsport]

Are the wheels the correct size for a narrow bodied 993???

They look like 18" speedline copies.

Correct 18" sizes for 993 NB

front ; 18 x 8 with ET 52

Rear; 18 x 10 with ET65

What size are yours???...

if not the same you may need spacers to get clearance.

[phelix]

Hmmm... http://www.pistonheads.com/gassing/topic.asp?h=0&a...

Each degree of negative camber will give you about 0.25 inches of increased clearance with the arch and the same reduction on the inside. But it is likely to result in increased inside tyre wear and tramlining. Me thinks you really should get the wheels sorted out otherwise you'll have a twitchy car that eats tyres.

[TISPKJ]

I have the exact same car and wheels but in a proper colour ....

No problems at all and running 285 Toyo R888's, the car appears to be running a bit of negative on the rear.

What size tyres are you running ?

[Agent Orange]

ARE UR ARCHES ROLLED?THERE IS A PORSCHE TOOL , USUALLY WITH main agents, like a wheel on a handle takes the lip off and rolls them up ............

[nick-moss]

I fitted GT3 Mk 1 rims to my 993 recently, I had to remove the spacers that were fitted with the standard rims, not sure if the spacers were standard, but your car may well have them as well. Is it one of the ex-Silverstone LHD cars that went through the Bonhams auction in July?

[ScottL]

Best take the car to a specialist such as JZ Machech, Parr or Fearnsport. They all know how it should be setup and can advise accordingly.

[lightweight]

I had a simmilar issue on my GT3 when I changed tyres to the newer N3 pilots Parr simply ajusted the geomotry settings to give me an extra 3mm that was needed

[bubster]

Thanks for your advise guys

The car is not running any spacers and the arches are not rolled, I only need about 3mm and the tyres will clear. I am running 265 rubber on 10" wheel which are the latest Pilots. I do feel the geometry could do with being set up so I will have to go that route I think. If a small adjustment to camber will give the 3mm I need that could be the way forward.

I do have feel geometry equipment at work if anyone can advise me of a good set up to run?


Hey TISPKJ, mine is in a proper colour, would have liked Riviera Blue tho or maybe yellow? I'm quite shy you know!

Nick, I think so, but when I had one of those test days at silverstone the car was completly standard apart from the cage..the car does not have spacers!

[nick-moss]

I have the other 993 that was sold in the same auction. It is not standard; apart from the cage it has H&R springs, Bilsteins, uprated pads and I suspect the ride height is lower than standard and the geometry definitely has a track bias. It behaves as well as my 993RS on track, but cost a third!