I was looking at the top mounts for the front suspension on my '13 991 C4, and it would appear that the three mounting bolts are through elongated holes that would allow for inward/outward adjustment. At the moment, from the factory, they are fully outward. Please see the photos.

Does this result in minimal camber? Can the camber be adjusted by loosening the bolts and placing them maximally inward? Would this result in maximal neg camber? Lastly, is this an adjustment that would require alignment check afterwards?

Please excuse my newbie questions -- I'm mechanically inclined, but I don't have much experience working on Porsches.

Thanks in advance

 

Yes, it appears you can add some negative camber, but chances are that by doing so you will also affect the toe. Would definitely get the adjustment done as part of an alignment.

 

Yes, looking at the geometry of the suspension, it's likely that the toe will be affected by camber adjustment. Will get it all adjusted at the same time.
Thanks for the reply.

 

If you're mechanically inclined and are going to play with it anyway, then why not play with it? Very seldom does anyone pay a shop to change alignment, then drive around, go back and have it tweaked again. You pays your money, you learns almost nothing.

Why not make your changes, drive around, maybe change it some more, see what happens? If you want to correct for toe changes simply place a straight edge across the wheels and measure side to side in front of and behind the wheel. This after all is precisely what the shops do, only with jigs that make doing it faster and more repeatable. You can do the same at home with a framing square.

Worst case, after trying several options you have a shop set you up with their recommendation. It sounds like you are already headed there anyway. My bet though (if you actually do try this) is you learn it is really hard to notice any difference at all, and develop a deep suspicion that most guys doing this do it for looks, and think it improves handling mostly because having paid a lot of dough they refuse to believe it went to waste.

Best case, you discover you can feel a difference. In this case you are still much better off having experimented, because now either you're able to set it up just how you want for free or, if you decide to have a shop align it anyway, you will now be in a much better position to evaluate their recommendations. (And will by now be almost dead certain that for the vast majority its looks and money, right down the line!)

 

Those are some valid points, but the main issue for me isn't so much how the car is handling as much as I'm noticing some significant tire wear on the outer edge now that I've begun bring the car to the track, particularly the front tires. I'm hoping that reducing the camber with allow for more even tire wear. Any performance gain would be a bonus. I'm not fussed about the aesthetics of more/less camber.

I don't have the necessary tools to be adjusting toe in/out, so will likely just have the shop do it.

 

Track rats just mark the original location on top and on the lower rods with a magic marker, then loosen them and shove them all the way over at the track and set toe with a string. Do the rears too. When track day is over, our them back to the marks. I've done that so many times on cars I can't even count them all. It's fast, effective and cheap.

Do a search for String Alignment and you will find videos and tutorials on it.