On board air systems?

What does the hive like?

I've been seeing good things about viaire systems This one in particular, but is there a better option or a good homemade method? 

I've seen a few write ups about using the AC compressor but that's not something I want to mess with in my black truck with black interior that the AC amazingly still works in. 

I don't want to run tools, just adjust tire pressure for wheeling and rally cross. Maybe a train horn, or if I go with adjustable shocks down the road. My biggest requirement is not taking up bed space, but I'm open to the back seat of the truck. 

I've considered it in my tow rig for the same reasons as you, but always come back to "why bother with the complexity and permanent install when I can just toss my $30 harbor freight air tank in the back and it has plenty of air for that kind of stuff...."

Viair seems to be the one to get if you get one, though.

What size tank? Can you fill all four tires with it?

This is more or less what I intend to build for my rig. Should get the job done for minor air up and air down of tires as well as my future plans for AirLift leveling kit for towing.

http://www.fourwheeler.com/how-to/electrical/1701-dirt-cheap-onboard-air-supply/

I had a legit On board air system on my last wheeling rig. It was expensive but also well worth it for airing up my 37's after being out on the trail. My current rig isn't running that large of tires and I will be doing overlanding instead of hard core offroading or rock crawling so I don't have a need for a high CFM or Duty cycle. 

In reply to B13Birk :

I've been using one of the compressors in that article in my rigs for the past like 10 years. I had to fix some solder connections two-ish years ago and just replaced the hose three weeks ago. Not bad for a $50 compressor.

I was going to follow that article for my truck. For the exact same purposes that you were looking at. I restaurant opening or bought that same compressor version from Harbor Freight. With the leads that are that long I couldn't find the need to permanently mounted. Put it in a 50 cal ammo can that is waterproof and it lives in the bed of the truck for when I need it now.

I'm partway into converting a separate a.c. compressor to grease and mounting that in my Tacoma. I am retaining my factory a.c. if you have the space in your engine bay and abilities to fabricate the brackets, I highly reccomend it above any 12v or co2 tank system available. It's much quieter than 12v, dosent have a finite limit like co2 does, and can run an impact gun at normal pressures for removing lug nuts and stubborn suspension bolts. Plus, they are actually very low maintence for the performance they put out, only requiring grease every 100 hours of operation. They do require an air tank to be installed as well, so you don't kill the a.c. clutch by short cycling it, but unless your tow rig is a tiny suv you have the space. And, if you are doing air shocks or airbags, not having to listen to or wait for a 12v compressor to fill them or make adjustments is a wonderful thing.

When I looked into onboard air when I was doing 4x4 stuff it seemed not worth it. I just got one of the recommended 12v portable inflators and it works great even for filling up 32"+ tires

https://www.harborfreight.com/air-tools/air-compressors/12v-100-psi-high-volume-air-compressor-69284.html

I mounted one of these under the hood of the Samurai. Not the fastest compressor in the world but it did the trick for air up when returning to pavement. On the Samurai the coil hose was even long enough to reach all the tires.

If you want an onboard 12v air system, look at the Puma compressors.  They're well liked, higher output than most of the Viair stuff and cheaper than the high end Viair stuff too.  

Personally, for when I need air while out somewhere in the Jeep,  I just toss one of the $100 Porter Cable pancake compressors in the back.  Runs fine off the 1500W inverter I've got installed and puts out more air than most of the 12v compressors on the market for a lot less $$$.