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Originally Posted by camcojb
He's a ride and handling engineer for GM, so he gets to design and play with some cool stuff. He also does a lot of track time with his job and his personal cars. He appears to be open to new technology as am I. If I could retain or improve my handling but get a better ride I would be interested. The car is going on Power Tour next year and being that I'm not a young pup anymore I like a nice ride.
One thing I haven't figured out about your systems; does the ride height and stiffness work hand in hand? In other words, if you backed off the pressures for Power Tour will it also lower the car height? I do like the idea of having both, the ability to back the pressures down to make the car ride soft for cruising, and then being able to adjust it back up for track use. Seems like the height moving around would wreak havoc with your alignment settings.
Jody
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The ride height and stiffness are connected...to a point. If you inflate an airspring to its designed ride height there is a window or "sweet spot" where small changes in air pressure will affect the spring rate much more than the load capacity [ride height]. Different airsprings exhibit this tendency more than others. It is influenced by the style of airspring [convoluted or sleeve], the shape of the airspring lower piston, and even the weave of the reinforcing fabric of the airspring. In english, you can manipulate the spring rate within maybe 1/2" of the design height of the airspring without significantly affecting your ride height. If the real world I set my alignment at the ride height that exhibits the best ride quality. When I intend to hit the highway I bring the car back to that specific ride height so my ride quality and alignment settings return as well. You can easily substitute "track performance" for "ride quality". In most of my cars the best track performance has come by using the highway ride height air pressure [whatever that may be] and cranking up the shock valving by about 4 clicks on the shocks. On a couple of my cars [the 71 Camaro and the 69 Mustang] I lower the rear air pressure a bit to let the rear of the car roll over and bite.
I still find shock valving, tire pressure, and sway bar setting VERY important when looking for track performance. Everyone has their own idea of how to juggle these parameters. Working with the air pressure is yet another tool. As with any tuning you have to be careful not to tune yourself out in left field! [don't ask me how I know that]
One interesting thing I found on my 69 Mustang...the car wanted to push pretty bad at the Kansas autox. I lowered the air pressure in the front to let it roll over and bite. What was actually happening was by lowering the air pressure I was inducing more static negative camber into the frontend which put more tire on the pavement through the corner. The next event I set the air pressure back up where it used to be and set more static negative camber. The car seemed to like that much better. It was 2 different tracks so a direct comparison was not possible but the frontend of the car was not washing out like it did before so I feel progress was made. The point is that the adjustability of the air suspension allowed me to, in effect, try a different alignment setting very quickly. This is just an example of one individual and one car.
I think that is possibly the biggest advantage of an adjustable suspension...the ability to quickly tune a car to current track or road conditions. Theroretically it would be possible to acheive all of this with traditional suspension. The more experience the tuner has the quicker this tuning could happen. But when you need to drive home or go to another track, [or add weight like passengers, fuel, or luggage] the tuning would have to start over.
Brian Hobaugh SCCA National Tour June 2014
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