Deflation
The following compares the STIS with using an ARB tire deflator, which removes the tire valve core. The tires are four (4) 315/75 16 Goodyear Wranglers with Kevlar being deflated from 43 psi road pressure to 18 psi for trail running
Individual ARB deflation = 7.5 min for all four down to approx. 18 psi
STIS tire deflation = 4.0 min down to exactly 18 psi.
Inflation
Using the 24 volt Puma air compressor and a 25' 1/4" air hose it took 14.75 minutes to inflate the four tires from 18 psi to 43 psi, including checking tire pressure.The STIS took 11.0 minutes to inflate 4 tires to exactly 43 psi (while allowing me to do other things).
Connections (see above):
1. Top feed hose from the Puma air compressor.
2. Bottom hose supplies all four
tires, via three T fittings and clip-on Milton air chucks.
3. The left ball valve is for airing down all four
tires.
4. The right ball valve connects to a Schrader tire valve to check system pressure.
All ball valves are closed in the default position and opened only for a specific operation.
Air hoses
I have a 3/8” hose from the Puma compressor to the manifold and to the supply hose going to a T- fitting connecting two hoses on the left and right side of the truck. These have quick connects on either end and can hang out of the door and when not in use I tuck them under the seat frames. For both the left and right side of the truck I have separate ¼” air hoses with a T-fittings in the middle, which connects the Puma air supply to all four tires using Milton cilp-on air chucks.
Air Down
When I want to air down I connect the ¼” tire supply hoses to the truck’s Quick Connects. This connects all four tires to the center manifold, and then I can open the purge valve to air down all for tires at the same time.
I close the vent valve and open the Schrader valve to check the average tire pressure and adjust as necessary. If I wanted two tires at a higher pressure I would disconnect these tires first and continue airing down the two lower pressure tires.
Air Up
For airing up I start the Puma and connect all hoses as described above. When the Puma tank is pressurized I open the upper and lower valves and all four tires inflate at the same rate and pressure.
I must close off the compressed air supply to check the tire pressure, because I can’t get a steady reading when pumping and it can damage the gauge. Continue airing up until the desired road pressure is achieved. If lower pressure is desired for two tires, disconnect the air chucks for those tires first and continue airing up the other two tires
