A low to the ground sports car not only looks sleek, but in theory is that much more performant. Air can't get under the car, it's going to be more aerodynamic and thus be faster right? Sort of... the devil is in the details!
Let's start off by addressing the most common thought: The GM Engineers knew what they were doing... but had some restrictions. The GM engineers needed to make these cars perform, but also be livable. The car needs to be fast, but if it can't even get into a gas station because it's so slammed, owners are going to be pissed.
Needless to say, the more you lower a car, the further away from the factory geometry and travel you will get. Now the smart folks may go "Well if I lower the car I'm just further into the engineers travel, it's no different..." and indeed... you are correct. To consider the difference though, let's say you are lowered 2"... and then hit a bump that would compress the suspension 4". You're now 6" into the suspension where the engineers had only planned on there being 4" of travel. Add in additional camber, maybe some toe-in or out depending on how you want the car to handle... well now you're starting to get noticeably outside of the original engineered geometry.
So all that said, we've compiled the various ways to lower the C5 Corvette and organized them from most to least effective.
Lower the Car on the Factory Bolts and/or Lowering Bolts
The GM engineers are of course pretty darn smart and indeed maximized the suspension geometry for the designed ride height. The engineers did however leave some adjustability in the factory leaf springs, both to accomodate any imperfections in the manufacturing and/or assembly part of the process, and to accomodate different spring rates and how that can change ride height. Given two identical suspension where the only change is spring rates, the stiffer spring will sit higher.
The factory lowering bolts do indeed allow for some lowering of the suspension, and for most folks it'll do everything you need unless you're running some high aspect ratio tires to try and fill up the wheel well. If you happen to fall into that situation though, the solution is getting some aftermarket lowering bolts that will let you drop the car down even further.
PROS:
- Lowers the car 1-2".
- No to fairly minimal cost.
CONS:
- Will probably affect factory geometry negatively if just done by itself.
Add Adjustable Bump steer
Bumpsteer is when the front wheels move in or out during their travel changing the toe in/out of the car. This can adversely impact handling. You can however get these adjustable tie rod ends that will change the bump steer of the car. With these in place you can measure toe in over travel, and adjusting the tie rod ends up or down will allow you to adjust the curve of toe over travel, ideally achieving a perfectly neutral toe from start to finish of travel.
PROS:
- A near guaranteed way to fine tune your suspension travel.
CONS:
- Easy to set incorrectly, or if installed with no measurements could make things worse.
- Good luck finding an alignment shop that will do this for you, and even better luck finding a place that won't charge an arm and a leg for doing so.
Lower the car on Coilovers
Coilovers are a worthwhile upgrade to the suspension on you Corvette for a variety of reasons. From simply replacing your probably tired fiberglass leaf springs and factory shocks to adding in adjustable compression and rebound, going with coilovers can improve ride quality and/or handling. Coilovers are also frequently adjustable in height, which would let you lower the car.
Some coilovers can be lowered by adjusting the perch on the shock body, while others simple adjust height via spring tension. Some rely on a bit of both. Whichever one you choose to go with, be sure to consult the manufacturer for the correct way to do so. You also may need to consider "tender springs" or "helper springs" to ensure that the spring is not loose when at full droop.
PROS:
- Improved handling characteristics and customized spring rates.
- Can improve ride quality.
- Adjustability may allow your corvette to better handle dual duty such as street/track, street/ax, etc etc.
CONS:
- Fairly expensive, and if cheap units are used they won't last as long
- Likely requires aforementioned adjustable tie rods.
Lower the Car with Drop Spindles
Now here's the "right" way to lower a C5 Corvette. You get drop spindles. These leave everything in the factory position and simply move the location where the wheel hub attaches. This in turn lowers the car but maintains all of the factory geometry that GM Engineers spent countless hours mastering.
PROS:
- The right way to do the job.
- Lowers the car and maximizes handling characteristics by retaining factory geometry.
CONS:
- By far the most expensive option at generally $2000 starting.
Honorable Mention - Airbags
So nobody at C5 Corvettes runs these personally but they do exist, and they have their merits. If you want to be able to get that lowered/stanced look, but air the car up to get over stuff, these are a pretty damn good option. We can't comment on how they handle on the track, and we're quite positive nobody seriously tracks cars with these... but if it's that lowered aesthetic you want but still have the ability to get in and out of your driveway or a gas station, these are a legitimate contender.
PROS:
- If configured to do so, can be adjustable from inside the car with an onboard air compressor allowing adjustable ride height.
CONS:
- Can add complexity that introduces additional failure points.
- Airbags may be more susceptible to failure than solid steel springs.