I have been thinking about putting a compressor in my truck lately as well. It would mostly be used for train horns, but would need to be able to air up my tires as well.
I have been looking into purchasing this system from siege engineering:
http://cgi.ebay.com/ebaymotors/ANVIL...2605QQtcZphoto

I emailed the seller about the system being able to pump up tires, he told me that he uses this system for putting air in the tires on his H2.

Anyone have experience with this system, or any thoughts on this system?

 

I've seriously thought about going with one of the Hornblasters train horn setups. Then not only will you have your compressor, but REALLY freaking loud horns to have fun with!

 

yep he is right, i got it at pep boys for like $50 it works great i have been using it for about 2 years now, it will fill the 13 gallon tank to 125 PSI in about 10 min, and with that much air i can take all 4 38" tires from 10 psi to 35 psi in like 2 min, with the tank full and the compressor running, it works great, i did my whole install for under $100 but i had all the teflon air hoses allready from previose projects, along with all conectors and fittings. the only thing i spent money on was the tank and compressor and i mounted a air gauge in the cab along with a switch so i can moniter the air presure in the tank. good luck.

 

The bigger the tank and the higher the psi the better. It may be worth spending a little more. Just remember how those mud grapplers run at a very high psi. Those all in one jump start units would take a couple of days to air up!