[Dave S.]

The Superflow MV50 compressor sold by Pepboys, O'Reily's and other outlets is actually a surprisingly good portable 12 volt compressor for around $60. It clips onto the battery because it draws too many amps to use a cigarette lighter socket. I've used them on my Jeep for tires up to 33 inches tall and was surprised at how good that little inexpensive compressor really is. It actually competes well against much more expensive compressors.

My current offroad Jeep has big 35 x12.50 (315/75-16) inch tires so I use a 20lb CO2 tank and it's super fast and allows you to run air tools off of it. I can fill around fifty 35 inch tires from 15 psi to 32 psi before I even start checking how much is left in the tank. You can refill the cylinder for under $20 at places that service beverage tanks for restaurants, grow shops, home brew supply stores and fire extinguisher businesses. For the small volume of air required for your low profile Porsche tires you could probably get multiple racing seasons off of a single tank full of liquid CO2 even with a 10lb tank. I like it because its very fast and silent, and you can piece them together pretty cheaply. There is no reason to buy the expensive tank systems in the link Healthservices provided.

For your purposes, I'd recommend the inexpensive MV50. It should do exactly what you need. I carry mine in my daily driver all the time.