Wanted - C3 Fibreglass rear spring +8 inch lowering bolts

Daytona Vette

Well-known user
Yes the height issue is the same both sides of the rear. On the front whilst trying to fit the fender flares I discovered the driver side is about an inch higher than the passenger side so I figured might as well just replace the lot with semi coil overs rather than deal with cutting worn old springs and all the associated hassle of getting both sides level. Have ordered Van Steel coils for the front. I would love to have coil overs on the rear but i'm already way over my original 20 grand budget and can't justify rears at the moment but definitely going to think about it for the future.
I'm based in East London and have been meaning to join the club for ages and never got round to it, will get it sorted now you've mentioned it. With any luck being a member will help with insurance quotes as i've not had much luck so far, I think being 24 isn't helping!
I presume it is a small block otherwise springs for coilovers should be 550lbs - Coilovers at the rear not needed - best is a good Steel Spring Heavy duty if you want and single adjust shocks (same as the front)
East London - Get yourself to some of the Club Meets
Vettes are great and so is the Club - Look forward to you joining
Loads of Help and camaraderie
 

Rich

Administrator
I'm based in East London and have been meaning to join the club for ages and never got round to it, will get it sorted now you've mentioned it. With any luck being a member will help with insurance quotes as i've not had much luck so far, I think being 24 isn't helping!

Dazaa, please let me know if you help in signing up. Incidentally, did you get my email yesterday with some info on the Club?
 

Corvette

Well-known user
From your pic of rear suspension it's not the spring and standard bolt that's the problem, it's the enormous link for the rear sway bar. Disconnect the sway bar from the trailing arm and allow your spring to breathe. I've never seen a linkage so long.
 

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Daytona Vette

Well-known user
From your pic of rear suspension it's not the spring and standard bolt that's the problem, it's the enormous link for the rear sway bar. Disconnect the sway bar from the trailing arm and allow your spring to breathe. I've never seen a linkage so long.
Well spotted - Just goes to show why when having a geometry set up on a car, one should always disconnect any anti roll bar - When a car is stationery and not loaded there should not be any load / tension on an anti roll bar.
 

Dazaa

Well-known user
From your pic of rear suspension it's not the spring and standard bolt that's the problem, it's the enormous link for the rear sway bar. Disconnect the sway bar from the trailing arm and allow your spring to breathe. I've never seen a linkage so long.


Now that is very interesting, not something anyone else has mentioned on the USA vette forum nor my friend who checked out the car in the states before I had it shipped over...the previous owner of this car was, well let's just say he had some creative ideas for how things should be put together (which is why I had to rewire the entire car, it was a fire waiting to happen) and as he rebuilt all the suspension at some point in the early 2000's it wouldn't surprise me if the bolts are too long. I'm going to have a go at loosening them and see if that helps.
 

Corvette

Well-known user
Yes I got it, will get it sorted sometime this week, cheers!
You need to remove sway bar links and release the jack. Those links look about 4 inches tooooo long.

If your car is the red one on the trailer it has 73 gills.
 
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Daytona Vette

Well-known user
Some of us might question whether rear sway bars actually do anything to help handling?............................
Front ARB yes most certainly, but with Dazaa's problem, after Frank's well spotted Link issue I got to thinking I am sure the earlier C3s had rear ARBs as standard issue, but not on my 78 - Why? can only be if the 78 Shocks are stiffer or / and the centre of gravity on a 78 is lower - I need to do the maths on the standard tyre profiles of each.
 

Roscobbc

Moderator
Front ARB yes most certainly, but with Dazaa's problem, after Frank's well spotted Link issue I got to thinking I am sure the earlier C3s had rear ARBs as standard issue, but not on my 78 - Why? can only be if the 78 Shocks are stiffer or / and the centre of gravity on a 78 is lower - I need to do the maths on the standard tyre profiles of each.
Hi Barry - only hi-po C3's and BB cars had the rear anti-roll bars as standard - I believe later C3's may had them as standard. When you look how 'insignificant' the links from the ends of the ARB to the chassis are you might question the effectiveness - especially if you have other options to improve handling (like wider low profile rubber)
 

Oneball

CCCUK Member
If the drop links are the same length both sides and it’s not fouling on anything it shouldn’t affect the ride height.
However it wouldn’t surprise me if they’re touching the chassis.
 

Daytona Vette

Well-known user
If the drop links are the same length both sides and it’s not fouling on anything it shouldn’t affect the ride height.
However it wouldn’t surprise me if they’re touching the chassis.
I think the links are that long that they are acting to lift the chassis
 

Daytona Vette

Well-known user
Hi Barry - only hi-po C3's and BB cars had the rear anti-roll bars as standard - I believe later C3's may had them as standard. When you look how 'insignificant' the links from the ends of the ARB to the chassis are you might question the effectiveness - especially if you have other options to improve handling (like wider low profile rubber)
When you go round a corner hard one side of the suspension is in tension and the other side is in compression, the ARB is there to try and equal out the forces to maintain the full contact patch on the side that is in tension
ARBs are especially needed with (not slow) vehicles with a high Centre of gravity
When the Range Rover Sport first came out, it was superior to the previous models in terms of less body roll - but was frequently wearing out the ARB bushes due to a heavy load made worse by the high centre of gravity - the fact that the bushes were wearing shows the links were doing the job.
You would not want to taz one around the lanes without an ARB - I nearly wrote an early RR off trying to swerve round a pigeon - the body and chassis were both swerving but not in unison so when you applied opposite lock the body was still going the oppposite way and so on and so on - lucky nothing coming the other way I was on both sides of the road trying to get it straight.
 

Forrest Gump

CCCUK regional rep
From your pic of rear suspension it's not the spring and standard bolt that's the problem, it's the enormous link for the rear sway bar. Disconnect the sway bar from the trailing arm and allow your spring to breathe. I've never seen a linkage so long.
They are long but Daza’s car is sitting 2” too high so just might be deliberate to keep arb in a horizontal plane. They may need shortening though when the car is lowered.
 

Daytona Vette

Well-known user
Front ARB yes most certainly, but with Dazaa's problem, after Frank's well spotted Link issue I got to thinking I am sure the earlier C3s had rear ARBs as standard issue, but not on my 78 - Why? can only be if the 78 Shocks are stiffer or / and the centre of gravity on a 78 is lower - I need to do the maths on the standard tyre profiles of each.
Doing the Maths: Early C3 F70 15 Tyres equates to 215 70 Later C3 225 70 Tyre - nothing in the wall height of the Tyre, 7mm if that - So blows out my theory of a later C3 possibly having a significantly better centre of gravity as a standard car (In my mind: standard older Vettes had taller side walls, as many other non standard C3 Vettes have shorter side walls, but they are on larger non standard diameter wheels, however although the side wall is smaller and you think the C of G is better, it is not because the overall diameter of the two tyres are the same - just a mind perception thing.

According to a later post by Ross - it was not a change from ARB on early Vettes to no ARB on later Vettes - Rear axle ARBs was a performance enhancement to the higher performing earl C3s - there are no higher performing later C3s and hence my 78 came without a rear axle ARB.
 

Forrest Gump

CCCUK regional rep
ARB's aid handling in corners but will effectively stiffen suspension over bumps. GM probably dropped the rear ARB in favour of better ride quality, and saved a couple of $$ too. We do sit right over the rear wheels in a C3.
My '75 has no rear ARB but I'd like to fit one eventually. You can see in my emoji how much body roll I get.
 

Roscobbc

Moderator
Andy, I'm not 100% convinced that a rear ARB will aid things so much on the rear end - as you note it effectively stiffens individual wheel travel (over what the standard spring/damper does) - there is a finite amount you can do here with a ARB without making the rear suspension (or front) 'thinking' its a beam axle........ my observation FWIW (on an otherwise stock suspension vehicle) is that an ARB can effectively 'make-up' for soft suspension rates....but only to a point. Far better (IMHO) to use modern low profile tyres on larger diameter rims and replace springs/dampers with more performance related items.
 

Dazaa

Well-known user
You need to remove sway bar links and release the jack. Those links look about 4 inches tooooo long.

If your car is the red one on the trailer it has 73 gills.

They were tacky aftermarket things put in place of the original egg crates, I cut them out and will be replacing the egg crates.
 

Dazaa

Well-known user
Andy, I'm not 100% convinced that a rear ARB will aid things so much on the rear end - as you note it effectively stiffens individual wheel travel (over what the standard spring/damper does) - there is a finite amount you can do here with a ARB without making the rear suspension (or front) 'thinking' its a beam axle........ my observation FWIW (on an otherwise stock suspension vehicle) is that an ARB can effectively 'make-up' for soft suspension rates....but only to a point. Far better (IMHO) to use modern low profile tyres on larger diameter rims and replace springs/dampers with more performance related items.


From the responses i've received over on the USA forum, the sway bar fitted to my car is far too thick and a few people have suggested removing it all together which i'm probably going to do.

Daza's 71 Restomod build thread - CorvetteForum - Chevrolet Corvette Forum Discussion If anyone is interested!
 
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