lowering a c6 vette
02-04-2010, 04:31 PM
#2
The question first would be, "how low do you want to go"? The factory bolts usually can get you down about 1-1.25" from the "average" off the assembly line ride height.....
The "cliff notes" of lowering a C-5, C-6 'Vette is A) get the car up on some ramps, so you have a little room to get under it; B) in front, turn the wheels full lock, either direction, to get at the factory bolts; C) place a block of wood on a floor jack pad, and lift the spring, to take the tension off the adjusting bolt (DO NOT scratch the spring, it's a composite); D) turn the screw counter clockwise, counting the number of turns; E) lower the jack; F) turns the wheels full lock the other way, and repeat these steps on the other side of the car, turning the adjusting screw the same number of turns.
The rear is easier... A) locate the long bolt that is between the spring and upper cushions; B) using a ratchet and open end wrench, "loosen" the bolt until there are about 2-3 threads showing between the top of the nut and the end of the bolt; C) repeat on the other side, again counting the number of turns.
Take the car off the ramps, and drive it around for about 15-20 minutes. Try to drive on a road that has undulations, but not potholes, to "work" the suspension, and get the a-arm bushings to flex and adjust to their new position. If you really want to do it right, then measure from the lower a-arms' inner pivot bolts to the ground, and adjust so both sides are the same height from the ground. (yes, I know it's easier to measure the height at the tops of the wheel wells, but sometimes the fenders aren't "dead nuts, side-to-side) Keep in mind the rear has to be about 1/4" higher, to provide the "aerodynamic rake" the car needs for high speed stability.
This should take a couple of hours and "zero" dollars. I dropped my C-5 just over an inch this way....
The "cliff notes" of lowering a C-5, C-6 'Vette is A) get the car up on some ramps, so you have a little room to get under it; B) in front, turn the wheels full lock, either direction, to get at the factory bolts; C) place a block of wood on a floor jack pad, and lift the spring, to take the tension off the adjusting bolt (DO NOT scratch the spring, it's a composite); D) turn the screw counter clockwise, counting the number of turns; E) lower the jack; F) turns the wheels full lock the other way, and repeat these steps on the other side of the car, turning the adjusting screw the same number of turns.
The rear is easier... A) locate the long bolt that is between the spring and upper cushions; B) using a ratchet and open end wrench, "loosen" the bolt until there are about 2-3 threads showing between the top of the nut and the end of the bolt; C) repeat on the other side, again counting the number of turns.
Take the car off the ramps, and drive it around for about 15-20 minutes. Try to drive on a road that has undulations, but not potholes, to "work" the suspension, and get the a-arm bushings to flex and adjust to their new position. If you really want to do it right, then measure from the lower a-arms' inner pivot bolts to the ground, and adjust so both sides are the same height from the ground. (yes, I know it's easier to measure the height at the tops of the wheel wells, but sometimes the fenders aren't "dead nuts, side-to-side) Keep in mind the rear has to be about 1/4" higher, to provide the "aerodynamic rake" the car needs for high speed stability.
This should take a couple of hours and "zero" dollars. I dropped my C-5 just over an inch this way....
02-04-2010, 11:02 PM
#4
Here's some install instructions I found. Lowers up to 2.5"
C6 LOWERING BOLT INSTALLATION INSTRUCTIONS
VEHICLE MUST BE IN THE AIR ON JACK STANDS OR ON A LIFT IN ORDER TO DO THIS INSTALLATION.
ONCE CAR IS SUSPENDED YOU CAN START WITH THE FRONT SUSPENSION. FIRST REMOVE LOWER SHOCK MOUNT BOLT. THEN REMOVE LOWER BALL JOINT NUT AND DROP THE LOWER CONTROL ARM DOWN TO ALLOW ACCESS TO THE SPRING ENDS. REMOVE EXISTING SPRING BOLTS LOCATED ON EACH END OF THE SPRING BY USING A 10MM SOCKET OR WRENCH. REPLACE THEM WITH THE NEW SUPPLIED BOLTS. ONCE THEY ARE INSTALLED YOU CAN RAISE OR LOWER THE SUSPENSION BY TURNING THE BOLTS IN OR OUT. WE USUALLY SCREW THEM IN LEAVING A 1/2”-3/4” BETWEEN THE LARGE ATTACHED WASHER AND SPRING, DEPENDING ON YOUR DESIRED RIDE HEIGHT.
THE REAR SUSPENSION BOLTS ARE INSTALLED BY USING THE SAME PROCEDURE.
ONCE YOU ARE FINISHED AND SUSPENSION COMPONENTS ARE REPLACED, YOU CAN MAKE ADJUSTMENTS BY SIMPLY RAISING THE END OF THE CAR THAT NEEDS ADJUSTING AND TURNING THE BOLTS UP OR DOWN.
A FOUR WHEEL ALIGNMENT IS RECCOMENDED ONCE YOU ACHIEVE A SATISFIED RIDE HEIGHT.
C6 LOWERING BOLT INSTALLATION INSTRUCTIONS
VEHICLE MUST BE IN THE AIR ON JACK STANDS OR ON A LIFT IN ORDER TO DO THIS INSTALLATION.
ONCE CAR IS SUSPENDED YOU CAN START WITH THE FRONT SUSPENSION. FIRST REMOVE LOWER SHOCK MOUNT BOLT. THEN REMOVE LOWER BALL JOINT NUT AND DROP THE LOWER CONTROL ARM DOWN TO ALLOW ACCESS TO THE SPRING ENDS. REMOVE EXISTING SPRING BOLTS LOCATED ON EACH END OF THE SPRING BY USING A 10MM SOCKET OR WRENCH. REPLACE THEM WITH THE NEW SUPPLIED BOLTS. ONCE THEY ARE INSTALLED YOU CAN RAISE OR LOWER THE SUSPENSION BY TURNING THE BOLTS IN OR OUT. WE USUALLY SCREW THEM IN LEAVING A 1/2”-3/4” BETWEEN THE LARGE ATTACHED WASHER AND SPRING, DEPENDING ON YOUR DESIRED RIDE HEIGHT.
THE REAR SUSPENSION BOLTS ARE INSTALLED BY USING THE SAME PROCEDURE.
ONCE YOU ARE FINISHED AND SUSPENSION COMPONENTS ARE REPLACED, YOU CAN MAKE ADJUSTMENTS BY SIMPLY RAISING THE END OF THE CAR THAT NEEDS ADJUSTING AND TURNING THE BOLTS UP OR DOWN.
A FOUR WHEEL ALIGNMENT IS RECCOMENDED ONCE YOU ACHIEVE A SATISFIED RIDE HEIGHT.
Last edited by 99Bluz28; 02-04-2010 at 11:12 PM.
02-05-2010, 07:03 AM
#5
When I lowered my C-5, in the front, I was able to turn the bolts roughly 3 full turns. That's not a lot of "real estate" on the bolt, but it dropped the car a tad over 1", as much as I wanted to go on an F45 equipped car.
