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Discussion Starter #1
Looking at putting in OBA in my JKU. No lockers, just a high output compressor for airing 35" tires up in a timely manner. I've looked at the Viair complete system and the ARB compressor. The Viair comes with a tank, but I'm not convinced I need a tank for airing up tires. I'm also concerned about mounting location. Where do people normally mount these? I'd prefer to not install something in the interior of the Jeep, but I'm not sure if that's even an option. My perfect solution for this task is on my TJ - I have a Warn Powerplant HD. However, that is entirely too big for the custom behind the stock bumper mount I'm going to do with my Warn VR10S.

Opinions welcome - what do you prefer and why?
 

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I've been considering on-board air as well, however the options that have higher CFM output than a portable compressor get really pricey if I recall. All I've looked at is Viair and the array of options is a bit overwhelming so perhaps I'm not looking at the right combination of things.

I believe a lot of folks install under the hood.. I'll be watching this thread...
 

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Do you want it hard mounted or would portable work? The advantage with a portable is that you can put the unit in your footwell with the ac blowing on it while you are airing up, which will help cool it down. I run the smittybilt 5.6cfm portable which is too big to really mount anywhere, but airs up fast.
 

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Discussion Starter #4
I should have specified. I do not want a portable unit. I want something hard wired. I strongly prefer nothing in the interior of the cabin, so under hood is preferable.

@mhicanders - look at Quadratec at the Viair complete system. $399, supposedly contains everything you need. FYI, it's $350 on Amazon (but I'm pretty bad about finding what I want on Quadratec and ordering on Amazon. Prime shipping is pretty cool and they're almost always cheaper. )
 

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Here is the kit that I initially looked at when I first started thinking about OBA: Dominion OffRoad Jeep JK CMF OnBoard Air System I have talked to a rep from EAD about it and think I will probably go with it when the time comes, though it is a bit more expensive than what has already been discussed in this thread. I like the idea of having an air chuck mounted on each side, as seen in the pictures, and having everything else mounted under the hood.
 

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I have the high output ARB mounted under the hood and it does great airing up 35's. It has the option to to run air lockers if you ever decide to go that route. There is a quick connect cable so that interfaces easily with the Spod.

Air up time with the 35's from 12-15 pounds to 30 pounds takes about 2-3 minutes per tire.

Northridge Kit

Product Number ARBJK2012-13-COMPRESSOR-KIT
Fits JK 2DR 2013, JK 4DR 2013
 

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Honestly. If you're just using it for airing up. A tank will probably be the cheapest, easiest, and fastest bet.

If not get the mini arb locker one. I have it for my swayloc but it fills my 37s alright. Not fast. But 35s are a much smaller tire.
 

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Honestly. If you're just using it for airing up. A tank will probably be the cheapest, easiest, and fastest bet.
...
Portable tanks take up a lot of space, how large a tank would one need to air up a set of 30's?

Make sure you find out the details, CFM being very important for tire air up time as well as duty cycle. Some of the 'kits' I've looked at don't identify exactly which compressor they come with so it's difficult (if not impossible) to find out what the details are.
 

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Subscribed.. Been curious as well, buddy I wheel with runs the ARB high output one under the hood.. Aired up my stock 32" in about a minute a piece. Don't think I want to spend that much though.
 

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I did a test using a couple of the cheap MV50 compressor kits. One I hard wired, and plumbed with 1/2" airline, through a manifold, a water separator and an air tank, the other I used as it was designed (portable kit-in-a-bag).

Started with the air tank (2.5 gallon) charged to the 150psi cutout, and compressor at ambient temp.
The air tank was depleted to line pressure (60psi) filling the first tire (31"x10.5"x15) from 15psi to 32 psi. Saved just over 30 seconds filling the first tire. After that the other three tires took the same amount of time to fill with a constant line pressure of 60psi.
So the tank only really saved time on the first tire.

The interesting part was the difference between the mounted kit, and the portable kit. I used the same filling line and fitting on both kits. The mounted kit saved almost two minutes of time over all four tires compared to portable kit, and that was without using the tank. So with the tank it saved 2-1/2 minutes.
The difference was caused by pump speed reduced through voltage drop on the subpar motor cables, versus the correct gauge wiring used on the mounted compressor.

Now the MV50 has a good reputation for a $50 pump. It has a built in thermal circuit breaker, and an 80A relay. Just the cables are undersized for the length supplied, and the wire caps should be replaced.
Best bet when using it is to break out a lawn chair, and use one of the built in Jeep bottle openers to pop open a cold one when it's time to air up.
This kit gives a whole new meaning to "bottle neck on the trail"... ;)
The other thing noted is that the air fill line from the kit is very restrictive (1/4" curly hose supplied with kit). So a 3/8" or larger fill hose would do a faster job, as the compressor moves more air at 30psi than it does at 60psi.

So in summary:
* Tank is great for the first tire, not so effective after that, unless the compressor CFM overcomes air usage.
* Proper motor cable size for length is important
* A 3/8" air hose will fill faster than those 1/4" diameter curly hoses
* Two air compressor kits are better than one (I keep the portable unit in the vehicle to share with trail buddies, and as a redundant air source).

I think for the Jeep, I'll get two Viair 480 compressors, and plumb them through a manifold into a single tank. I was originally thinking about the twin ARB, but I like the redundancy of two separate compressors.
Hth,
 

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I use a 10# co2 setup, takes up vey little space on the roll bar. Pieced together my own kit (tank, reg., hose), then bought the Powertank bracket and roll bar clamps. I had a hard time forking over the cash for the bracket and clamps, but found this to be the most secure method in my JK. Tank transferred over from my TJ which was a much cheaper mounting option with quick fist clamps to rear side wall.

Tank will last at least 5 fill ups on 32"s going from 15psi back up to 33.

image-1856567262.jpg



image-2565521839.jpg
 

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It seems there's a point of diminishing returns. The difference in CFM at a given pressure (say 30psi). If you look at the Viair 440P $297.97 - 2.26cfm the 90p $79.97 at 1.13cfm. So for about twice the CFM (and duty cycle) you pay about 3.7 times the price. I'm not saying it isn't justified (perhaps other features on the 440p) however it seems like a lot of technology, you pay a bunch for smaller performance increases when you get to the upper end of things.
 

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Tank will last at least 5 fill ups on 32"s going from 15psi back up to 33.
That's my problem with air tanks plus I have 37s. I had one, loved how fast it was but a). it always ran out with one or more tires left to fill and b). the closest place to me to get it filled took an hour round trip while you wait for them to fill it etc.

Compressors are not fast but they are reliable and you don't have to keep getting them filled.
 

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I have been looking into the oba options as well and had pretty much given in to putting a pump under the passenger seat. Easy with an Arb wired to a Spod. I don't want it under the hood.

Has anyone ever considered having a pump in the front bumper, assuming you don't run a winch? I have a JKURX so I know there is room in the bumper. Seems like it would be simple to plumb a quick-disco for the hose. It will be somewhat away from engine heat, out of sight, and have some weather protection. The only real down side I see might be the low mount in high water.

I this a dumb idea?
 

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I've got a twin ARB mounted under the hood in a modified dual battery tray. I didn't want portable & I didn't want it in the cab. It was expensive, but it's awesome.
 

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I too have the ARB twin under the hood and tied into my sPOD. The ARB replaced my MV50 which was a good little compressor. The ARB is a racecar and MV50 is a reasonably priced sedan.
 

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