The addition of the Sun Performance QuickAir2 on-board air in the TJ was a fairly simple project. I opted to make the QA2 compressor a permanent installation rather than getting the portable compressor setup. As usual, I ended up spending too much time trying to figure out where to install it. Once that was decided, the installation took just a couple of easy hours.
|After looking over the available space in the rear of the TJ, I decided
to mount it just behind the right rear roll bar, where the bar attaches to the fender
well. A better mounting spot would have been in front of the roll bar mounting
point, but that space is occupied by my automatic antenna coupler for the Icom 706
Given the close proximity of the hard top and the Jeep's sheet metal, I was only able to use 3 of the 4 mounting holes. This seems to be of no major problem, as the three in use seem to hold everything in place quite well. I used 1/4" bolts with nylocs to fasten the compressor in place (did not want any vibration to loosen up the mounts).
Quick Air2 flow rates --->
2.18 cfm @ 0 psi @ 22 amps
1.76 cfm @ 20 psi @ 22 amps
1.45 cfm @ 40 psi @ 24 amps
1.20 cfm @ 60 psi @ 25 amps
0.99 cfm @ 80 psi @ 26 amps
0.85 cfm @ 100 psi @ 26 amps
0.77 cfm @ 105 psi @ 28 amps
Duty cycle rating:
|Power for the compressor is obtained from a pair of
#8 gauge wires that
enter the rear end via a hole in the roll bar. I long ago removed the rear seat and
the seat belts, and the seat belt mounting slot on the rollbar provides an entry spot for
the wiring without the need to drill any additional holes. The wiring runs the
length of the frame up to the engine compartment. I mounted the supplied 40 amp
resetting breaker on the fender well, and attached the positive wire to it. The
other post on the breaker is connected to the main feed point on the fuse panel where it
receives the +12V from the Optima battery.
The switch that came with the compressor was installed in the negative lead at the base of the compressor. Since I've never been fond of using the vehicle frame as a ground return for the negative battery connection, another #8 gauge was installed and connected in the engine compartment at the negative battery terminal.
|The local 4x4 store was out of the QuickAir air hose
assembly, so I got one made for ARB. Since the quick disconnects are not of the same
style, I swapped the male unit on the compressor so it would match the air hose (the air
hose came with both the male and female connectors). Since I do not use an air tank,
the air hose must be of the open flow design so it does not overload the compressor when
you do not have it attached to the valve stem on a tire. When it is not connected,
the compressor runs and the air exits at the "working" end of the hose.
There is a warning label on the compressor that cautions you about the compressor getting hot.....it does! There is a duty cycle time limit for the compressor. At the pressure I run in my tires, it gives me about 40 minutes of run time. Depending on how low I drop my tire pressure, it takes between 1 and 3 minutes to inflate my 30x9.5 tire. It will take the tire from 18 to 40 psi in 2 minutes and from 25 to 35 psi in a minute flat. I checked my 32"x11.5" BFG MTs the other day and QA2 took 2.5 minutes to raise the tire from 15 go 25 pounds. Unless you plan on airing up the entire group after the run, you should never come close to exceeding the run time limit of the compressor.
In summary, I really like my QA2 setup. It is easy to use, easy to get to, and gives me some piece of mind. As I write this, I have used it on my last two trips and found it to work very well. While the tires are airing up, it gives me time to dig through the cooler and find the last cold soda before hitting the highway and heading for home. I would recommend this compressor to anyone who wants off-road air capability.
Late note: It has been several months since I wrote the above article. Since then, I have used it dozens of times and I still like it just as much, and maybe even a bit more. I had the pleasure of having a friend along a couple of trips back who had never aired down before. He dropped his tires to about 15 pounds and was very pleased with the result. I aired him up at the end of the day, and he too was impressed at how quickly his tires were back to street pressure (he was running P215s or something like that on a non-Jeep vehicle....argh!!!!) But none the less, he has been converted over to airing down to smooth out the ride and improve the traction on his vehicle. (Now, if I can convince him to get QuckAir2 so he'll stop using mine!)
February 2001: The QA2 has been chugging away for about 18 months now and has seen a LOT of use. It is pretty common for me to air up another vehicle at trail's end, along with mine of course. I would calculate that I have about 3~4 years worth of "single Jeep" work out of it so far. Can't complain about that. In another month or so, my 32" BFG MTs will be replaced with 35" MT/Rs. I know I won't be getting the same air up times I have become use to thus far. I guess I am going to have to plan for a few more minutes in order to fill up void in these tires.
February 28, 2001: I received e-mail from a gentleman named Eric Lund about a month ago. He wrote:
I came across your website today....Very cool.
We are the manufacturers of your QuickAIR2 compressor. After reading your section about the compressor install, there is one thing that I would like to suggest. That would be to upgrade the power supply lead to #8AWG wire. It has been our experience that running any wire size smaller than that, especially when the unit is located far from the battery, may lead to premature failure of the unit.
Send me your mailing address and I'll send you our Part# WP208. (20 ft. #8AWG)
Best Regards, Eric
I answered his note and explained that I would be most happy to install the correct gauge wire (my QA2 was a demo unit and it did not come with all of the extras). Today, when I arrived home, there was a package sitting there waiting for me. I opened it and found the 20' wiring harness that Eric had told me about. So, I have edited the section above to reflect that one should be using 8 gauge wire and I will be installing it on my Lady before my next wheelin' weekend.
wanted to take a moment here to thank Eric and Sun Performance. As
far as I am concerned, Eric exceeded the customer service rating of
A+. He had zero obligation to do what he did. I know now, more
than ever before, that I made the right decision when I bought my
QA2. The fact that I have a great pair rocker panels from them to is
just extra icing on the cake. A big thanks to Eric and Sun
June 3, 2001 - I got the flow rate and pressure specs from Sun Performance so the performance of their 3 Quick Air compressors could be easily compared.
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