C3 suspensions
Melting Slicks
Joined: May 2015
Posts: 2,365
Likes: 428
From: Cape Girardeau Missouri
Drifting
Joined: Jan 2012
Posts: 1,908
Likes: 129
From: Fredericksburg Virginia
Interestingly enough, the transverse fiberglass leaf spring is still utilized in the current C7 production car, front and rear. While the "stuff" around the spring has changed over the years, the principal of the rear suspension is amazingly similar then to now.
Guess it wasn't such an awful idea.
So...to answer your question...the C3 suspension was not only essentially unchanged from 1968 to 1982 (the change to a 'batwing' rear end did not alter the rear suspension), this is an exceedingly similar setup to the C2 Corvette from 1963 to 1967.
To the untrained eye, the chassis that underlies any Corvette from 1963 to 1982 would appear virtually identical. Pretty amazing.
Guess it wasn't such an awful idea.
So...to answer your question...the C3 suspension was not only essentially unchanged from 1968 to 1982 (the change to a 'batwing' rear end did not alter the rear suspension), this is an exceedingly similar setup to the C2 Corvette from 1963 to 1967.
To the untrained eye, the chassis that underlies any Corvette from 1963 to 1982 would appear virtually identical. Pretty amazing.
Last edited by keithinspace; Aug 22, 2016 at 04:25 PM.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,113
From: Crossville TN
Spring rates, monoleaf rear spring (later C3's), changes in shock absorber design and rates (all were hydraulic, I believe), tires went from bias-ply to radials [that's a BIG change], vehicle weight and weight ratio [front to back] differences over those 14 years. The frame and suspension design was basically the same except for those differences.
Last edited by 7T1vette; Aug 23, 2016 at 12:21 AM.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,113
From: Crossville TN
Shock and spring rate differences can have pronounced effects on ride quality. Later C3's were smoother and softer riding, as GM wanted to move away from the 'power sports' vehicle and toward the 'luxury sports' vehicle.
ANY C3 that recieves four new Bilstein shocks is a different car.
ANY C3 that recieves four new Bilstein shocks is a different car.
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Thread Starter
Racer
Joined: Aug 2011
Posts: 429
Likes: 24
From: Charlotte NC
Shock and spring rate differences can have pronounced effects on ride quality. Later C3's were smoother and softer riding, as GM wanted to move away from the 'power sports' vehicle and toward the 'luxury sports' vehicle.
ANY C3 that recieves four new Bilstein shocks is a different car.
ANY C3 that recieves four new Bilstein shocks is a different car.
Le Mans Master
Joined: Oct 2007
Posts: 7,422
Likes: 955
From: Tennessee/Rhode Island
The 63-83 suspension and frames are basically the same overall design with some minor differences. The good news is that any C3 can be made into whatever you desire in terms of ride comfort or handling since there are so many aftermarket parts available to convert to your taste. For example, take any base suspension C3 that you want to convert to a gymkhana suspension type car:
Front 550 springs, 360 composite
Bilstein Shocks (HD/Sports) or like I have, HD's in front with Sports in the rear
1 1/8 inch front sway bar (78-82's)/7/16 inch rear sway bar (SB...BB had a 9/16 inch rear sway bar)
255/60/15 or similar tires
Next level suspension:
Add a front spreader bar
Rear competition adjustable Heim struts
17/18 inch rims with ZR tires
QA1 adjustable shocks
Borgenson Steering box
Poly sway bar bushings
Poly upper and lower control arm bushings
Front 550 springs, 360 composite
Bilstein Shocks (HD/Sports) or like I have, HD's in front with Sports in the rear
1 1/8 inch front sway bar (78-82's)/7/16 inch rear sway bar (SB...BB had a 9/16 inch rear sway bar)
255/60/15 or similar tires
Next level suspension:
Add a front spreader bar
Rear competition adjustable Heim struts
17/18 inch rims with ZR tires
QA1 adjustable shocks
Borgenson Steering box
Poly sway bar bushings
Poly upper and lower control arm bushings
Burning Brakes
Joined: Jan 2012
Posts: 943
Likes: 73
I'm looking online at 80-82's so that helps understanding them. My '74 still has the original front coils and rear leaf has 20 yrs since repair work. I don't want the ride height to change but need to get back to original strength of suspension most likely though. Thanks.
Drifting
Joined: Jul 2007
Posts: 1,889
Likes: 23
From: Kansas
I used the front & rear factory sway bar, with Poly bushings. The Borgenson box, with spreader bar. Aluminum upper A-arms, sets caster in about minus 5. or was it the camber. Bilstein H. D. Shocks front & rear. 460 # front springs & a 360 # rear Composite spring, & adjustable Heim joint struts with 8" bolts to adjust height. I now can go a ninety miles an hour with out it Wandering off the road. When I started I just added a non-factory heavy sway bar, it almost swayed me off the road. so be careful with what you add. Gene
Thread Starter
Racer
Joined: Aug 2011
Posts: 429
Likes: 24
From: Charlotte NC
I used the front & rear factory sway bar, with Poly bushings. The Borgenson box, with spreader bar. Aluminum upper A-arms, sets caster in about minus 5. or was it the camber. Bilstein H. D. Shocks front & rear. 460 # front springs & a 360 # rear Composite spring, & adjustable Heim joint struts with 8" bolts to adjust height. I now can go a ninety miles an hour with out it Wandering off the road. When I started I just added a non-factory heavy sway bar, it almost swayed me off the road. so be careful with what you add. Gene
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,444
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
beginning in 1978 the frames were stiffened up, larger diameter shocks, 24 gallon gas tank, better high back seats, and 255 width tires. The rounded rear window makes for useable cargo area.
I don't feel safe in stock c-3 corvettes. They are not a sports car. highly modded suspensions actually make them a pleasure to drive.
You can actually put 25 gallons in my 1979 and it is so nice to not have to worry about a next gas station for 500 miles on a trip
I don't feel safe in stock c-3 corvettes. They are not a sports car. highly modded suspensions actually make them a pleasure to drive.
You can actually put 25 gallons in my 1979 and it is so nice to not have to worry about a next gas station for 500 miles on a trip
Racer
Joined: Jul 2013
Posts: 366
Likes: 19
The 63-83 suspension and frames are basically the same overall design with some minor differences. The good news is that any C3 can be made into whatever you desire in terms of ride comfort or handling since there are so many aftermarket parts available to convert to your taste. For example, take any base suspension C3 that you want to convert to a gymkhana suspension type car:
Front 550 springs, 360 composite
Bilstein Shocks (HD/Sports) or like I have, HD's in front with Sports in the rear
1 1/8 inch front sway bar (78-82's)/7/16 inch rear sway bar (SB...BB had a 9/16 inch rear sway bar)
255/60/15 or similar tires
Next level suspension:
Add a front spreader bar
Rear competition adjustable Heim struts
17/18 inch rims with ZR tires
QA1 adjustable shocks
Borgenson Steering box
Poly sway bar bushings
Poly upper and lower control arm bushings
Front 550 springs, 360 composite
Bilstein Shocks (HD/Sports) or like I have, HD's in front with Sports in the rear
1 1/8 inch front sway bar (78-82's)/7/16 inch rear sway bar (SB...BB had a 9/16 inch rear sway bar)
255/60/15 or similar tires
Next level suspension:
Add a front spreader bar
Rear competition adjustable Heim struts
17/18 inch rims with ZR tires
QA1 adjustable shocks
Borgenson Steering box
Poly sway bar bushings
Poly upper and lower control arm bushings
Thread Starter
Racer
Joined: Aug 2011
Posts: 429
Likes: 24
From: Charlotte NC
beginning in 1978 the frames were stiffened up, larger diameter shocks, 24 gallon gas tank, better high back seats, and 255 width tires. The rounded rear window makes for useable cargo area.
I don't feel safe in stock c-3 corvettes. They are not a sports car. highly modded suspensions actually make them a pleasure to drive.
You can actually put 25 gallons in my 1979 and it is so nice to not have to worry about a next gas station for 500 miles on a trip
I don't feel safe in stock c-3 corvettes. They are not a sports car. highly modded suspensions actually make them a pleasure to drive.
You can actually put 25 gallons in my 1979 and it is so nice to not have to worry about a next gas station for 500 miles on a trip
Pro
Joined: Mar 2006
Posts: 530
Likes: 85
From: SW Ohio
beginning in 1978 the frames were stiffened up, larger diameter shocks, 24 gallon gas tank, better high back seats, and 255 width tires. The rounded rear window makes for useable cargo area.
I don't feel safe in stock c-3 corvettes. They are not a sports car. highly modded suspensions actually make them a pleasure to drive.
You can actually put 25 gallons in my 1979 and it is so nice to not have to worry about a next gas station for 500 miles on a trip
I don't feel safe in stock c-3 corvettes. They are not a sports car. highly modded suspensions actually make them a pleasure to drive.
You can actually put 25 gallons in my 1979 and it is so nice to not have to worry about a next gas station for 500 miles on a trip
I will replace with heaver springs & Bilstein HD shocks
Chuck
Le Mans Master
Joined: Oct 2007
Posts: 7,422
Likes: 955
From: Tennessee/Rhode Island
Hello Sir. Thanks for all the great input you bring to this forum. I installed longer leaf spring bolts to lower the ride height, and even cut the bolts an inch because they were so close to the ground. Would the QA1 adjustable shocks be a better way to adjust the rear height, and allow a shorter bolt, like the original 8" bolt? Thanks, Frank.