Awhile back I decided to replace the CO2 setup with a compressor. I want a system that will work well for more than just airing up tires. I also want to operate air lockers, airbags, and run a few power tools.
I debated a lot between an ARB unit or Viair kit. I know there are a few other options out there but Viair and ARB were the two I found to be mentioned the most. I was looking at Viair Ultra Duty kit and the ARB twin compressor. The Viair kit was about $50 less and includes a 2gal air tank. Both are 100% duty cycle. When comparing compressors you have to dig a little deep to find comparable stats. The closest I could come was the ARB twin flows 4.65cfm @ 29psi and the Viair flows 1.52cfm @ 30psi. It's easy to find 0psi specs but I feel they are pretty meaningless but for comparison the Viair is 1.76cfm and the ARB is 6.16cfm.
Ultimately I decided to go with the ARB for a couple of reasons. #1 would be the specs I listed above and another big reason was their level of quality. Viair does also make a twin compressor setup that is about $30 more than the ARB but it still doesn't have nearly the performance. The only complaints I found with ARB compressors was their higher price, which was the only thing in the negative column for me.
The ARB twin compressor is essentially 2 compressors mounted together with a little manifold. There is also a cooling fan to help keep operating temps down.
The ARB twin compressor comes with 2 harnesses, one for power and the other to activate the pump.
The power harness has a big negative lead and 2 large power leads with a 40amp fuse on each, one lead for each compressor. That harness is about 6ft long. The harness for the activation switch includes plugs for 2 locker solenoids, plugs for 2 locker activation switches, and plugs for the switch to activate the compressor (including the switch itself). That harness is 10ft long.
I think my biggest complaint was that the ARB compressor doesn't come with a quick connect. It doesn't come with a hose either but that didn't really bother me because I already have the hoses from my CO2 setup. The compressor has a 1/4"NPT fitting so all you need is a quick connect with a male 1/4"NPT to be ready to connect an air hose.
One of the biggest decisions I had to make is where to mount the compressor. There were 3 locations I was considering; engine bay, cab, or the bed. The cab is most centrally located but I was afraid the compressor would be too loud for the people sitting in the truck while I aired up tires (and after using the compressor I do believe it would be awfully loud in the cab). The engine bay would make wiring the power leads the easiest and protect the compressor from the elements. However my motor likes to run hot and I was worried the heat would affect the durability of the compressor. So I decided on the bed.
The compressor base has rivet nuts. So I threaded M6x1.0 studs into the rivet nuts with loctite.
When it came time to thread the nuts on, it was extremely difficult to reach the studs between the panels of the bed so that will be good for theft deterrence.
I wanted to protect the compressor from stuff in the bed and provide it with some additional shelter so I made an aluminum cover for it.
You will notice the little tube looking thing connected to the compressor. That
is a little manifold with 2 ports for the air locker solenoids. It is an additional item that I thought I was going to need but really didn't. I had planned to put the compressor under the overhang on the toolbox but it wouldn't fit there. If it had fit I would have needed to get the hose connection out where I could reach it. I thought the solenoid manifold would help with that and provide a future location for the locker solenoids.
I had to get power for the compressor to the bed. It will draw upwards of 56amps so I used 4ga cable connected to the battery with a 60amp fuse.
I made my own cable clamps with thin strips of aluminum wrapped in electrical tape. Luckily there are enough holes in the frame I didn't have to drill any holes. I used abrasion sleeve on the section of cable that runs through the area next to the tcase because I couldn't get in there with a cable clamp.
I used the compressor today to air up tires after a trail run and it works great. I only needed air up my 37" tires about 15psi, and it made quick work of it. It only took about a minute per tire.