air suspension

[paulnl]

does anybody have experience with air or hydraulic suspension?. hard for the track and adjust to softer for long distance cruising.

[Logan]

My good friend and I both drive S550 Mustangs daily as well as autocross regionally. I’m on coil spring and dampers, and he has installed a complete Air Lift suspension in his. I can tell you it’s a pretty slick system overall, he can raise or lower his car something like 6+ inches. From laying the frame on the ground tires and wheels tucked inside the fenders all the way to 4x4 mode sitting so high you can stick your fist between the top of the tire and the bottom of the fender. Very handy actually...on steep approaches he can lift the front or rear and once over the obstacle lower back down.

Now...as far as the track performance, this is where it gets fuzzy. There’s no such thing as “Spring Rate” for an airbag. So you can’t compare it to any other regular suspension, including mine. I know what my rates are, and can be pretty statistical in calculating swaybar rates and damper curves, but he cannot. The stiffness of the bag is more about pressure and volume. If you want a soft ride on airbags, you need to have less air pressure in the bag, but not less volume (or it would be bottoming out everywhere). We have still not achieved a balance in his car that gets a softer ride than my traditional springs give. Maybe we’re not doing something right, but it’s going on 2-3 seasons now with plenty of tinkering and it’s still about the same as the day they were installed. During autocross, he lifts the car nearly to the top to clear his big wheels and tires, but this makes the bags pretty firm and plus his center of gravity is now way higher than a stock Mustang.

Takeaway here: Airbag suspension is a nice setup for street cars who want the WOW factor of dropping it low, or the convenience of raising the car on command. For pure track performance, stick with traditional springs and dampers.

[Straversi]

Search 35 Ford Hoonatruck. He put JRI hydraulic coil-overs in his truck.
-Steve

[railing]

https://youtu.be/Gg9ZxC_wKJM

No affiliation with JRI but that shows you a few things with them. My plan is to street drive 70-80% with the car, then autocross and track some too. This has been the setup I've been watching to see if the performance is there and might do this.