April 8, 2015

Future Shocks Page 4

At first this in-car thingy may seem like a frivolous gimmick-“we did it because we can” -but the in-car adjustor is not frivolous and is certainly no gimmick. We used it to fine tune the suspension as road conditions changed minute to minute. Future Shocks Page 4

We employed the adjustor like that for good reason. The best way to deal with severe corrugations is to accumulate enough speed so your vehicle can get on top of the peaks. The speed necessary to accomplish this is about 80km/h. The problem is that only a car with decent suspension will last the distance.

A related problem is that not all 4x4s can drive on corrugated roads at 80km/h.  A vehicle with soft suspension but poor damping can become unstable if corrugations meet up with  successive whoops or  dips common on Cape York, while a stiffly sprung vehicle will simply thunder over the same obstacles while reducing its occupants to a viscous paste.

With the Rancho- in-car kit -provided you have decent suspension components to begin with- you can fine tune the suspension for the changing road conditions, and do it quickly. On the worst corrugations we vented the system with the dash-mounted bleed valve to give us a softer ride. Although the dials read in five stages, compression and rebound adjustment is infinitely variable.

Typically, while travelling at 80km/h over bad corrugations, soft suspension settings produced a good ride but with noticeable body bounce over any sizeable bump. This is natural and what you’d expect since very suspension is in some way a compromise. The problem with the faster rebound inherent in softer settings is that when you hit a set of unexpected whoops your car will wallow or “float” a lot more and you’ll have to brake to stabilize the suspension. (Survival tip: Don’t brake in the bottom of a whoop or you’ll drive the front of your car into the face of the next whoop. If you can, brake on top).

When the corrugations disappeared and 100km/h again became feasible, we dialled in more compression and rebound damping, which firmed the ride noticeably and produced much less body roll. When engaged in serious 4×4 work we dialled up fairly hard settings to give us much more control. You can adjust the ride independently front and rear.

Tim didn’t bother to watch the gauges to judge how much air he was bleeding out of the shocks. He could feel through the air bleed valves how much air he was venting and really only ever glanced at the gauges to confirm his assessment of the suspension’s response. He was a good judge.

There’s no such thing as perfect suspension but with a bit of effort you can put together a system that gives you more pleasure from your four-wheel drive.

For those interested in this excellent suspension product we’d recommend they start with the one-dial system, which is easier to use and provides enough control for most off-road situations.

Rancho’s in-car system seems to make an inherent heavy 4×4 vehicle safer, more controllable on bad roads, and more comfortable. The Rancho’s set-up can also cut your trip times and save your car’s vulnerable underside components a lot of broken bones on the rough stuff. X

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