The C5 and C6 Corvettes are an amazing value whether you got one new off the showroom floor or you picked one up secondhand. Chevrolet has no doubt done a great job over the years keeping the Corvette in a price range attainable for many by making Vettes simple yet effective. One of the most obvious examples of this is seen in their suspension design for the C5s and C6s. GM utilized a transverse leaf spring in the front and rear, which allows for independent front and rear suspension while still keeping production costs at a minimum. But you can’t do a whole lot with those transverse leaves when it comes to making your 1997-’13 Corvette take corners even better, so sometimes it’s just more effective to go the coilover route.
Believe it or not, the conversion from leaves to coils is relatively simple, involving little more than unbolting some factory stuff and bolting new stuff in its place—save for a little grinding, but we’ll get to that later. What you get in return is a complete overhaul in the way your Corvette handles, but even more than that you get a whole lot more adjustability.
Aldan American saw the benefit of swapping in coilovers on the C5 and C6 Corvette so they jumped on it and put together a kit. They made our life and yours much easier by supplying custom mounting hardware that bolts their coilovers directly to the stock mounting points. Follow along as we take you step-by-step through the process of installing Aldan American’s C5/C6 Chevrolet Corvette bolt-on coilover conversion kit to a 2005 Vette.
1. Aldan’s C5/C6 coilover kit comes with everything you’ll need, including the four coilovers, mounting brackets and bolts, and even the preload adjustment spanner.
2. Before getting started, make sure to record a measurement of the car’s ride height from the ground to the top of the wheelwell. It’s easy to get excited when installing new parts and miss this step but you’ll thank yourself for doing so at the end.
3. OK, time to start unbolting stuff. We used a lift to make life easier for us but if you’re going to do this in your garage just make sure to jack up the whole front end so both tires are off the ground. Once you get the wheels off, start by unbolting the two bolts on the back of your brake caliper then use a zip-tie to hang the caliper out of the way.
4. Before removing the antisway bar endlinks and the old shock, use a floor jack to support the lower control arm. This will make loosening bolts much easier and keep the control arm from dropping suddenly when you’ve removed the stock shock absorber.
5. Next, unbolt the antisway bar endlinks and the upper control arm, which will allow the lower control arm to droop down enough to remove the shock when the time comes. More likely than not, you will have shims behind the upper control arm bolts so make sure you make a note of how many there were and put them all back in the same place when you reinstall the arm.
6. To begin removing the shock, open the hood and use a box wrench to remove the nut that holds the top of the shock absorber in place.
7. Once you remove the two bolts that connect the bottom of the shock absorber to the lower control arm you’re in the clear and can pull the shock out.
8. Next, you need to remove the transverse leaf spring. To do this, remove the four bolts—two on the driver-side and two on the passenger-side—that hold the leaf spring in place.
9. Make sure you’ve got one hand supporting the leaf when you get to the last couple of bolts, otherwise gravity will get the best of it.
10. Slide the coilover into place where the stock shock absorber was and tighten down the nut atop the coilover.
11. The bottom of the coilover also bolts into the same place as the stock shock for easy installation.
12. With the coilover in place, measure from the base of the collet to the base of the threads. As a rule of thumb, Aldan recommends 1/2-inch of preload as a good starting point.
13. Use the spanner that came in the kit to dial in that 1/2-inch of preload. Make sure to do the same for all four coilovers.
14. Now you’ll just need to bolt back in the upper control arm (don’t forget those shims!), the antisway bar endlink and the brake caliper.
15. This next part may or may not apply to you. In our case, there was a slight clearance issue where the antisway bar was pressed up against a coil.
16. We then removed the antisway bar and ground down the troublesome area until there was a little room to breathe between it and the coil spring.
17. Now moving to the rear. Before installing the rear Aldan American coilovers, use the provided hardware to bolt on the mounting plates to the top of each coilover. The instruction sheet will identify which is the left bracket and which is the right bracket.
18. The rear install is extremely similar to the front. The only real difference being the way the shock bolts to the control arm and the chassis, which we will cover—for everything else, refer to the steps used up front. The shock mount on the lower control arm consists of one long bolt and a nut that needs to be removed.
19. Up top, the upper control arm is also held in place by a long bolt and a nut on either side while the shock is held in place by two bolts that go into the frame.
20. Like the fronts, the rear coilovers slide right into the stock mounting locations used for the shocks. On the bottom, slide the long bolt through the coilover and lower control arm and tighten.
21. With the mounting bracket installed on the coilovers, the top of the coilover bolts in place using the two factory bolts and bolt holes.
22. With everything else bolted back up and tightened to factory specs, it’s time to get your Corvette back on the ground. Take some post-install ride height measurements to make sure it matches the pre-install height—and make adjustments if necessary—and then take ’er for a drive!
Photography by the Author