I'm getting new tires installed tomorrow by a Tire Rack installer that I have not used before. This is my first tire change, so is there anything I need to watch for? Do I need to get an alignment afterwards?

 

I always get an alignment when I get new tyres. Alignment is relatively cheap. Tyres are relativly expensive.

 

You don't need to get an aignment done, but as Scott said, getting one done or at least checking it when new tires are installed is a good idea to maximize tire life just in case it's off.

 

Shouldn't need an alignment unless they screw something up with the car up on the rack. In 30+ years I never remember needing an alignment just due to a tire replacement. However, on Porsches I generally change to my alternate tire/wheel set (ex., track set) and carry only the 4 tires/wheels into the tire shop.

 

I agree with Ray, Take the tires/wheels in by themselves. Less chance for any damage.

 

The tires themselves do not cause a need for an alignment. Having new tires installed usually does cause you to be at a place that does alignments, and you are there after enough time has passed since the previous alignment that your car very well may be out of spec to some degree (particularly a 993). I would have it checked. If it is not out of spec, then the time and cost should be significantly less than a full alignment.