FX3 Performance Question

[Rogue]

My 1991 Corvette came with the FX3 Adjustable shocks. The whole car has 36,000 miles including the shocks.

When I have the shocks set to Touring mode, the suspension gets soft and a bit bouncy when it hits a big dip on the road. It feels like there's not enough damping when hitting those kinds of bumps. But of course, the ride is much more comfortable. When I set the shocks to Performance, the suspension stiffens up dramatically and the car handles very good. Gone is the body roll and wallowing. Although, it's a bit harsh on the freeway bot dots we have here in SoCal. So, I tend to leave it in Touring mode 90% of the time. However, I hate the bounciness and wallowing. Is this trait normal in Touring mode? Or do I need new shocks? I realize my Bilsteins are 13 years old even though the mileage is low. Do shocks deteriorate over time as opposed to mileage?

 

[Tuna]

Unless you have leaking shocks, they probably do not need replacing.

Besides, it sounds about normal to me. I tend to leave my shocks set to the middle or Sport setting. This eliminates the ride issues you dislike without being as harsh as the Pref setting.

For myself, I perfer the Sport or Perf mode and rarely switch to the Tour mode unless I'm doing endless freeway miles.

 

[bradvette]

Unless you have leaking shocks, they probably do not need replacing.

Besides, it sounds about normal to me. I tend to leave my shocks set to the middle or Sport setting. This eliminates the ride issues you dislike without being as harsh as the Pref setting.

For myself, I perfer the Sport or Perf mode and rarely switch to the Tour mode unless I'm doing endless freeway miles.

I agree as well, with everything. I normally drive my FX3 in the sport setting as well

 

[c4cruiser]

In addition to the 3 dial settings, the shock valving also changes as speed changes. One of the inputs to the FX3 controller is vehicle speed. As speed increases, the controller send a signal to the actuator to increase shock stiffness.

One of the Corvette magazines posted a chart a few years ago that showed a graph of shock settings at each of the 3 dial positions and vehicle speed. One thing I remember was that the Tour setting at 70MPH was actually stiffer than the Performance setting at 25MPH.

Doug Rippie used to offer different PROM's for the controller that provided stiffer shock setting at each dial position. I believe you had to get a different controller that allowed replaceable PROMS, then you could get a variety of chips that fit the driving application.

Bilstein can rebuild the FX3 shocks if needed. Unless there is a lot of oil dripping from the shock, (a light film is OK as the oil is deliberately overfilled) the shocks should be fine. Bilstien can also re-valve the shocks to stiffer settings. I believe it's called Sirroco valving. Call them at 1-800-537-1085 in San Diego to see what they can do for you.

 

[Rogue]

Thanks for the reply guys.

I just wasn't sure if the bounciness was normal in Touring mode. In both Perf & Sport mode, the handling is awesome. I don't think I'd ever want a Corvette without an adjustable suspension. It's like a TV remote. Once you have it, you never want to go back!

 

[Tuna]

I like the FX3 suspension also. After 12 years and 100K+ miles, I bought a full set of new FX3 shocks for my old car. Even after all that, they still didn't have any leaks but, after installing the new ones, I can surely tell that the old ones were worn. The car is much tighter now. I wasn't bad before but I figured that 100k miles was enough. I think I'll send the old back to Bilstein next year and have them rebuilt and revalved.

Now if GM made a retro fit kit to put the new F55 MagnaRide shocks on the older Vettes - This system is on my 03 and it puts the FX3 to shame. Oh well, I'll just have to live with the 'old' stuff on the 'old' car.