Hi all,
I've finally had a few free moments to think and start planning out an onboard air system on my 2000 D2. My goal with these mods are to air up 4 32' tires, air up 2 feeder bags, and have the ability to air up others tires in case someone has a flat or compressor breaks. I originally installed a harbor freight air compressor similarly to Discoramas (I think that's the user, sorry if this is wrong but props to you for your set up) but after a few trips the air compressor has shown to be too small and slow (about 5 minutes per tire to inflate) and for about 100ish dollars more I picked up a Smittybilt air compressor ( ) and had planned to mount it in the old SLS compressor bracket but due to the bigger compressor size I'm planning on removing the bracket and bolting it to the frame. From there I have a 2 gallon air tank that I wanted to fit under the the truck but its too big :/, so instead I bought a 1/4 air manifold off amazon and plan on routing 2 air lines to the front and rear of the car (with air chucks under the hood and on the rear bumper somewhere) and one on each side, with cut to length air lines for left and right side tires. 2 slots will be used to inflate feeder bags in the rear springs for heavier loads and leveling out for a roof top tent. The last few slots will be used for gauges and an air down system (still have yet to plan). I plan to use this system primarily while overlanding/off-roading with the system depressurized when not in use, while in use being between 120-140 PSI

So my questions are:
Is the Smittybilt compressor any good? I have it but can easily return if there is a better one (ARB is a bit too pricy for me unfortunately)
Should I stick with 1/4 air lines? 3/8? I'm having troubling finding reliable sources of 3/8th air products. I've also heard from others that they have used semi tractor air lines but haven't read too deep into that.
Has anyone had any problems with feeder bags or know any good brands to buy?
Is 120-140 PSI a good range? my compressor can do 150 but don't want to push it to its limits.
Would a tank be a good idea for quick bursts of air for dusting off the truck or will the manifold and hoses hold enough air?
Any advice/tips/tricks that y'all have and want to share? My plan is very loose and I wont have enough to built this until April (want to order parts now and plan out now so I don't waste time later).

Thanks.

 

I'd buy a high output single cylinder ARB or find a similar VAIR. Have had good success with both.

 

I was looking at those but the prices were a bit too high for my budget. Love the look of the ARB and the inclusion of the tanks in their kits though.

 

A friend of mine has used the smittybilt compressor for a couple years now and it's still kicking. I think it's a decent compressor although, i'm not sure about mounting it outside/under the truck.

 

I'm not sure if this fits in to your plan or use case but I've read about installations where people have put the compressor under the passenger seat where the multi-disc CD changer used to go (that is, of you're not still using it!). Also, be aware of duty cycle- that smitty built unit claims it can run continuously for 40 minutes at 40psi but that time gets cut WAY down once you are pressurizing over 40 PSI. So for a given amount of pneumatic energy you have to decide if you want to run it in several cycles to store at a higher pressure in smaller tanks or use bigger tanks and run the compressor longer at less pressure.

 

I got a cheap one from HF and added a 1 gallon tank. Fits perfectly into the air suspension compressor tray. Cost me about $120 including all hardware, wires, hoses. A switch in the cabin turns it on, so I can start it while driving and have pressure right away when stopping. Of course the 1 gal tank is like nothing, but it provides a little buffer.

 

My first onboard air setup was a viair I found second hand. Worked as it should have for years. Took a lonng time to air up a 33 from 15 to 30. The Viair is a “constant duty” rated unit, so it was made to run run run. It came with a 2g reservoir - which really was not enough to use for an air tool in a pinch like I had hoped -

I wouldn’t mount it below the truck with the off road or over landing I do

 

​​​​​​​I looked at that and did some quick napkin math. 4 tires that need a combined total of around 37-38 cubic feet of air and the compressor running at its rated 5.5 CFM would only need to run for about 6-7 minutes (lets say 8-10 minutes as the compressor slows down due to pushing higher psi).. I'm planning at running around 15-20psi depending on the trail and airing up to 45 PSI for hwy driving. I do like your idea of mounting the compressor under the passenger seat and so ill have to test fit it today . I have a tank but no good way to mount it on the exterior of the car and because i still daily this car and plan to for the next handful of years I don't want to take away seats or space in the back.

 

​​​​​​​I remember talking with you on this and I really like your setup! I did what you did and found that it was a little too slow for me. the HF compressor was easy to modify but it only pushed between 1-2 CFM and the same napkin math as I mentioned earlier gave an estimate of about 27-28 minutes to air up 37 cubic feet of air. I tend to wheel in groups of 2-15 trucks and spending an extra 15 minutes on the side of the trail airing up is a bit annoying as I have to play catchup to try and make it to the next destination. I plan on wheeling at least once a month and so I'd like to put some money into a system that will pay off in trail time. I do plan on applying your idea of a bumper mounted air chuck to reach the back end of the truck if you don't mind.

 

I didn't expect more considering since it is one of the cheapest compressor in the 30-amp-class (draws about 35 amps measured). To me the performance is acceptable with 30.5" tires. I don't use it often and I am never in a hurry.