Is the ARB Twin Onboard Air the best solution?

[hoser]

Cool, I get it...you do you, but the discussion wasn't about if you or anyone cares or not, it was about if the valve was a restriction. That's it.

Exactly, less restriction and the compressor runs cooler and lasts longer.

Here's one test video on compressor performance, airing up (4) 37" tires from 10-35 psi (using Octopus) and measuring compressor temperature.
Results:

Milwaukee M18, 131 temp (of plastic housing?),
Time: 15:40 (had to do one at a time. Could not use Octopus, kept throwing error code). Used approx 75% battery

ARB dual, 250 cyl temp, Time: 8:30
Morrflate 190 cyl temp 126 hose temp, Time: 6:07

 

[TeCKis300]

The valve isn't a flow limiter per say, but it is a restriction. Obviously with enough pressure differential, flow can be increased.

The flow impact is at the pump. Pumps lose flow working against pressure. With a restriction, it's not just working against tire pressure, but also increased head pressure pushing air past that valve. The more air it tries to push through, the more added pressure it may see. As an example, it's not just working against say 30 psi of the tires, but possibly another 20 psi with the restriction, or a total of 50 psi.

Pumps inherently slow in flow/CFM delivered against increased pressure. Some handle this better than others depending on pressures it's optimized for. Or sidestep the restriction by using an octopus to fill more than 1 tire at a time.

 

[eatSleepWoof]

I've had an ARB twin installed under the hood (on a SLEE mount) for about 5 years now. No issues.

I cut off the piece of engine-cover plastic in the compressor area so that the compressor is not covered at all, and obviously open the hood when I use the compressor. I don't use it nearly as frequently as I used to, but at least once every few months. Love the compressor, and love having it where it's completely out of the way and ready to go at any time.

 

[Trollhole]

M18 Milwaukee and maybe a couple batteries. Easy, light, walk away while it's going, can swap it to other vehicles because you will always have someone in the group that is that guy.

 

[kcjaz]

Seems so.

Another thing to pay attention to and modify is their odd round screw on air filters (for lack of better term).

They clog with dust and crap FAST. I got in habit of cleaning them when changing truck oil, as part of my maintenance routine.

Then i got tired of it and just rerouted them to the airbox, like you would a diff breather

Little black circles, about 3” diameter

Lower right corner of this diagram

View attachment 3710555

You got a pic of your tubing and connections to the air box? Cool idea.

 

[hoser]

M18 Milwaukee and maybe a couple batteries. Easy, light, walk away while it's going, can swap it to other vehicles because you will always have someone in the group that is that guy.

The concern for me is storing Lithium Ion batteries in my vehicle... one that goes to Death Valley in 120+ degree weather. I've seen a fair share of LI fires. I do carry LFP batteries without concern.

 

[TeCKis300]

I go wheeling to chill and get away from it all, if it takes 30 seconds longer to fill or empty a tire who cares. and you still have to wait for the slowest guy in the group

To be fair, there's different realities.

For a typical robust compressor like a Viair 450P rated at 1.39 CFM @40PSI. Which is close to a Milwaukee Fuel 18V compressor rated at an even better 1.6CFM @40PSI. Below are the times to inflate. If inflating to towing pressures like 45 PSI, these times may double to triple. Then multiply that by 4. Sometime 6 or 8 as some of us have trailer tires to air up too.

So what some see as a relaxing 15 minutes activity for a smaller 33" tire. Now goes to 45 min to 1 hr slog, possibly in the sun or rain, for large tire rigs needing more volume and pressure.

That's where high performance dual compressors, high flow valves, and octopuses come in. Each can be a bottleneck and when used in combination, can really improve performance.

 

[Broski]

To be fair, there's different realities.

For a typical robust compressor like a Viair 450P rated at 1.39 CFM @40PSI. Which is close to a Milwaukee Fuel 18V compressor rated at an even better 1.6CFM @40PSI. Below are the times to inflate. If inflating to towing pressures like 45 PSI, these times may double to triple. Then multiply that by 4. Sometime 6 or 8 as some of us have trailer tires to air up too.

So what some see as a relaxing 15 minutes activity for a smaller 33" tire. Now goes to 45 min to 1 hr slog, possibly in the sun or rain, for large tire rigs needing more volume and pressure.

View attachment 3713691

That's where high performance dual compressors, high flow valves, and octopuses come in. Each can be a bottleneck and when used in combination, can really improve performance.

View attachment 3713690

I wheel a lot and run 39s In our group it’s never taken more the 10 or 15 minutes to do the chore.
For reference I air up my 39s in a minute 40 seconds per tire with my puma air compressor they’re half the price of an ARB dual.

 

[TeCKis300]

I wheel a lot and run 39s In our group it’s never taken more the 10 or 15 minutes to do the chore.
For reference I air up my 39s in a minute 40 seconds per tire with my puma air compressor they’re half the price of an ARB dual.

Stirring the pot. I like it. This beast?! That might be the right tool for 39s and maybe some are willing to compromise on trades for this.

 

[grinchy]

possibly in the sun or rain, for large tire rigs needing more volume and pressure.

you didn't even mention the worst - mosquitos!

 

[Heckraiser]

Stirring the pot. I like it. This beast?! That might be the right tool for 39s and maybe some are willing to compromise on trades for this.

View attachment 3713710

Yep, that's the good ol' PUMA! I ran mine like that with the 1.5 gallon tank for several years before I ditched the tank and ran the compressor directly. Time to inflate 4 tires didn't change. I think your earlier assessment that the tank sped up the first tire and slowed down the rest is correct. Takes up a lot less space without the tank and fits nicely under the hood of the 200 in front of the airbox.

:edit:

 

[hoser]

I wheel a lot and run 39s In our group it’s never taken more the 10 or 15 minutes to do the chore.
For reference I air up my 39s in a minute 40 seconds per tire with my puma air compressor they’re half the price of an ARB dual.

Stirring the pot. I like it. This beast?! That might be the right tool for 39s and maybe some are willing to compromise on trades for this.

It's more of a workhorse than a beast. Really popular 10+ years ago and has proven reliable. But the 1:40 fill time is just for the first tire.... unless you are waiting a minute for the tank to fill. The compressor itself is rated at 2CFM @40psi and would show it's speed if using an octopus.

 

[Broski]

Stirring the pot. I like it. This beast?! That might be the right tool for 39s and maybe some are willing to compromise on trades for this.

View attachment 3713710

Yes, But I ditched the tank and mounted it in the RQP it's not taking up any more room the the ARB twin and less then a Tank combined with a flow chuck it take about the same time as a tank.

And to stir the pot all the guys in our group are willing to help out but also all have there own air system whether it's a tank or OBA so 6 or 8 guys are not waiting to use the same system

 

[Broski]

It's more of a workhorse than a beast. Really popular 10+ years ago and has proven reliable. But the 1:40 fill time is just for the first tire.... unless you are waiting a minute for the tank to fill. The compressor itself is rated at 2CFM @40psi and would show it's speed if using an octopus.

I don't run the tank ! all 4 in under 8 minutes

 

[Broski]

I think everyone should run what works best for them. just sharing what works for me.

 

[hoser]

First Puma video I came across. He inflates (2) 37's from 10psi to 38psi. You can tell at the 4 minute mark he is not nearly at "highway" pressure yet. But yeah, I agree, we should run what works best for us. I do like having a tank though because I still use air tools and I like using compressed air to blow the dust out of my cruiser. I had sliders built to double as air tanks.

 

[TeCKis300]

I think everyone should run what works best for them. just sharing what works for me.

Agreed. That's in the spirit of this thread after all as the OP is looking for input and considerations, based on what works for others.

Thanks or highlighting the PUMA

 

[Broski]

To be clear a bigger tires need less air. this is well documented on the net. and again I'm using a high flow chuck
If the wire gauge or connections are not correct the compressor is not going to run at it's peak.
I took the time to test all of this

I don't even us a gauge, I ran tests and I know that at a minute 40 seconds I'm good to go.

Street pressure on a 80 is 32psi and less on bigger tires.

My last post on the subject.

Cheers

 

[hoser]

Sure... for anybody else....

If you go STRICTLY by load inflation tables, the larger tire will require less air for the same load as the smaller tire. I run 25 psi on one of my cruisers but I know I am at risk of overheating the tires. Large LT tires are at a higher risk of overheating when under-inflated.

I'm not the authority on this, the Tire And Wheel Association (TRA) is probably the biggest authority and they state 35psi is the lowest for many LT tires.

Performance wise, the PUMA compressor without the tank is the equivalent to the SINGLE ARB compressor.

 

[Boston Mangler]

M18 Milwaukee and maybe a couple batteries. Easy, light, walk away while it's going, can swap it to other vehicles because you will always have someone in the group that is that guy.

Amen Sir