For a while now I've been sitting on the air = suspension kit that I got from Air Lift (http://airliftcompany.com). For the = Hollister Syncro meeting I finally made the time to pull them out of = the box and install them. Since my Syncro is currently on the = road (without me!!! who would have thought) I installed them in Steve = Schwenks Syncro Westy first. Steve has the Bilstein shocks and = stock springs installed.
The air suspension looks like two red rubber = cylinders with metal hose connectors on the top. Kind of like a = rubber beach ball. It was easy to install. I lifted the = rear of Steve's van so that the springs expanded all the way. = Then the two cylinders were pushed into the inside of the spring by = deflating them and inserting them between two adjacent coils. I = connected a short piece of hose and a tire valve (all part of the kit) = to each cylinder. Using cable ties, I attached the valves to the = brake lines that run along the top of the trailing arms. This all = could be done without taking the wheels off. Now the system was = easily inflated with a standard tire pump (I used a bicycle = pump). Because the volume of the suspension is so small it took = only 5-6 strokes to bring it up to the max. rated pressure of 25 = PSI. I set the pressure to a conservative 20 PSI and Steve drove = his Syncro to Hollister like that.
Now the air suspension pretty much fills out the = whole space inside the spring from side to side and from the bottom of = the trailing arm to the rubber stop on top. Fully inflated the = rubber stop just touches the air suspension. As the suspension = contracts the rubber stop is pressed into this air ball. This is = similar to having a spring with a progressive spring rate. The = more the rubber stop presses into the air ball the more pressure inside = the ball builds up. The increase in air pressure inside the ball = is proportional to the increase in force that is pushing against the = rubbers stop. By changing the initial pressure with a tire pump = the "air spring rate" is changed. Increasing the = pressure makes the air suspension stiffer (higher spring rate), = decreasing it makes the air suspension softer (lower spring = rate).
Initially I was concerned that the rubber stop might = puncture the air suspension. I called Air Lift and talked to one = of their engineers. He insured me that this is what these things = are designed for and it should be save.
In Hollister Steve was quite impressed with the air = suspension. His van was about 2/3 loaded on his way to = Hollister. He thought the air suspension was an improvement over = his stock setup. Steve also tested the air suspension on the = trails with his twins sitting in the back. The pressure was left = at 20 PSI. More positive remarks.
Next the air suspension went into Mark Drillock's = Syncro Westy together with the new Betts springs. Mark has also = the Bilstein shocks installed. In Mark's Syncro we tested the air = suspension at different pressures: 25 PSI (max. rated pressure), 15 PSI = and 0 PSI. At 25 PSI the rear became very stiff. I was = almost thrown out of the rear seat at big bumps. At 15 PSI the = rear was perfect. It now had the right damping. The = traction of the rear axle was much improved. At 0 PSI the air = balls didn't seem to have any effect on the suspension as = expected.
Everybody was quite impressed with the way the air = suspension changed the behavior of the rear axle depending on the = initial air pressure. By simply changing the air pressure the air = suspension can be easily adapted for different load and road = conditions. Low pressure for an empty van, high pressure for a = fully loaded van. Low pressure for highway driving, high pressure = for off-road driving.
We also tried the air suspension on Craig Drillock's = (Mark's brother) 1982 Vanagon Westy with 1.9l turbo diesel = engine. At 25 PSI the we were able to lift the rear by = 1/2". Guess that's great news for all you 2WDs with sagging = rear springs (the Syncro was not raised because of the higher = springs). Handling and traction of the 2WD was greatly improved = with the air suspension in place. We did a couple of turns on the = dirt track and it was amazing to see the difference between the front = (without air suspension) the rear (with air suspension). While = the front felt rather unstable and was breaking out left and right the = rear seemed to be on tracks. Completely stable.
Everybody that got to test the air suspension wanted = to get one. So I'm trying to put a group purchase together. = There are also two compressor kits available for the air = suspension. Theses kits consist of a compressor, one or tow = pressure gauges and control buttons, and all necessary hoses and = connectors. These items can be installed in the van. With = the gauge(s) and controls mounted on the dash board the air suspension = can be controlled while driving. With the dual-gauge kit the two = air balls can be controlled independently. I think that could be = very useful for 2WD Westies. This way the weight of the water = tank or other off-center weight could be easily equalized. Here = are some prices for the Air Lift suspension that I got from the = internet:
Air suspension for =
Vanagon =
$70
Compressor kit with single =
gauge $110
Compressor kit with dual gauge $159
I hope to get these prices further down if we get = enough people together. Please send me a p-mail if your = interested. Please indicate which item(s) your interested = in. A similar kit is available from Firestone. I don't have = personal experience with the Firestone kit nor have I heard from = anybody who does.
Cheers,
Peter