Techart Wheel Problem

can anyone help???? i have just purchased some techart wheels from tech 9 and am currently having some probs. Tech 9 have previously fitted these wheels (19in x 11in 5 spokes et52) on the rear of non facelift 3.4 y reg cab with no probs. mine is a 3.6 2002 C2 (well, v late 2001) model. the wheel are sticking out about 10mm outside the arches! it has techart suspension fitted, and the camber set to help the wheels into the arches (cant remember if thats neg of pos camber!) the fronts are A1 - look sexy although there off until i can have tem all matching!! any ideas , any thing is helpful - techart in germany dont seem to have a clue Joe

Make sure there are no spacers fitted to your car. Porsche allow for (I think) up to 10mm spacers to improve handling with standard wheels - maybe someone fitted them. This would take the TechArt wheels outside the arch as they have a bigger effective offset. Chuck the spacers out and all will be well!! Ian W

What offset were the standard wheels - form recolleciton they should be around ET50, in whcih case the techart ones should be 2mm further into the arch than the old ones - something not right there at all.

If they have done this to make the car look right cosmetically, they definitely don't know what they are doing! Putting too much negative camber will upset the handling and cause excessive tyre wear. If you would like a copy of the Technical Service Bulletin which shows the offsets of the 17" and 18" wheels, send me an email and I'll attach it to a reply.

hi chaps Thanks for all you responses. the car is at tech 9 and i will let you know the feedback from them they are puttting on more camper so i will let you know. if they muck it up they will be hearing from my solicitors. i will not be happy if they much up the handling! thanks joe

Joe Soon after I got the car I had a full wheel alignment, after having a new set of tyres fitted. My independent found that there was too much negative camber on the rear, which had caused the tryes to wear out on the inner edges. Since putting it right, I have done 12000 miles, and the tyres have all worn perfectly evenly. I would be worried that Tech9 are going to put on more negative than is correct, just to make it look better. Having said that, they have had some good feedback on this forum, so would seem to be reputable even if they are a bit expensive. The correct rear camber for C2's and C4's is -1° 10' +/- 15'. Unless you have a camber gauge it would be difficult to check accurately, but a plumb bob, careful measurement, and some simple trigonometry might give you a good approximation.

Here is the info on the factory wheel offsets If you comapre the 17" wheel option of the earlier cars (255 rear tyre ET55) to that of MY02 onwards with 18" wheels (265 or 285mm rear with ET65) then it is clear that on the later cars with bigger rear tyres there is a need to move the tyre inboard to avoid rubbing the wheel arch edge). You don't say what size tyres, but given the 11" rear rim width i'd assume 275mm minimum, in which case i'm now not surprised. Your ET of 52 means the rim is 13mm more outboard than the factory 18" option (and not dissimilar to the 10mm discrepancy you quoted originally). I'm no expert in geometry, but i'd say you'd need some serious camber to get the tyre edge safely within the arches.