AGVI

I hope the bushings don't crack on you.

SuperBuickGuy

only way to get clearance to keep it from hitting the frame. I needed clearance for the sway bar from the tire, so I heated and bent the bar ends in, then moved the mounts on the t-arm by welding them to the side. Soon I'll put heim joints in place of that set up... but until then, it's ugly but it works

Roco71

I bought my 8 inch bolts and bushings from Zip about $37.00

69firebird

have 8's (came with 6 link) need 10's

Carl Granquist

So, if I might ask, to lower the passenger rear side 1/2" but not changing bolts...
Tighten, to shorten?

7T1vette

Longer bolts lower the rear....so you back the nut off what you have to lower it some.

wabco40

I used VBP 10" bolts, these lower the rear as much as I would like to go

The bolts are listed in the C4 suspension section on their site.

They also have C4 12" bolts but I don't think a C3 would go that low.

gcusmano74

Me neither. It looks way too short. The link should be long enough to get the bar end much closer to horizontal, with the car at regular ride height. The way it is now, the short link might limit the travel of the suspension. IMHO, not good..

DAVID SLUDER

10 INCH BOLT WITH VBP REAR SPRING AND 18" WHEELS

DAVID SLUDER

gbvette62

We had a scary situation with 8" bolts, at NJ Motorsports Park, this past weekend. I crew for a team, that vintage races Corvettes. We were racing a 64 Corvette this past, and broke an 8" spring bolt!

With 2 laps to go in our qualifying race, the left spring bolt sheared off, at the nut. Luckily, all that happened was that the left side of the spring, hit the track and ground off the end of the spring. I've seen the main leaf break (especially on 74-77 Corvettes), but I've never seen a spring bolt break before.

We had a spare spring with us, but no spare 8" bolts, just 6" inchers. With the 6 inchers, the car sat up a little higher in back than we'd like, but we did make the main race. Unfortunately, while running second with 3 laps to go, we were hit in the right rear by a clown in a Ginetta (G4???), bending the trailing arm and destroying a perfectly good Torque Thrust wheel.

cottoneg

I would get the 10 inch bolts. I was trying to set the D height on my car. I think the spec for the D height is 1 1/4…… Anyway, a 8 inch bolt would not have been enough. I did not use all of the 10 inch bolt. Since is the bolt was below rim height I was concerned if I had a flat. So I cut the bolt at the nylock. The bolt was grade 8, and it took a while. If you do set your D height, make sure both side match. Better yet, have gas in the tank, and your weight in the drivers seat.

LAddams

12" bolts came on my project car. rear sits nice and low but bolt ends are scary close to the ground.Im thinking Ill have to swap in the 8" I also have and see how it looks.

360chris

Where do you find the 10" bolts (other than the hardware store). Does anyone offer them with the provision for the cotter pin?

Thank you in advance.

Kerrmudgeon

Just an update as the original OP, we installed the 8 in. kit from zip and it brought the car down to the stock height. Our problem was the damn aftermarket spring that made the car sit about 4 inches too high. Thanks for the pics and ideas. Cheers! and.....
Happy New Year!

Greasyfingers Nick

Let's revisit this..I am mainly interested in C3..for me a 1981..but anyway..the topic is how to adjust ride height, and..where to measure it for consistency..some measure tire top to wheel arch, some floor to wheel arch, some floor to frame a certain distance ahead of rear, and behind front wheel hubs. For the front, can height be adjusted at all short of cutting springs? Does Caster affect it? for the rear, were 7 inch outer spring bolts stock for all C3? The main parts vendors have 8 inch that they list as "long for increased adjustment". Can the 9 or 10 inch for the C4 be used? It is easy to see in this thread that too long can have big problems with tires..or if a flat. Also, it seems the factory shop manual specs floor to frame are a bit "stately". What brings all this on for me is twofold: one with a new standard steel transverse spring and 255-60R-15 BFg tires, my floor to wheel arch rim is 29.5..too hi it seems. Yet at the frame ahead of rear wheel the factory distance, the height is at 7.5, below the factory spec.
All this to get to the next step which is 4 wheel alignment, (after I complete the wheel bearing replacements). I have seen the Duntov article on rear..are these specs improvements on the shop manual? and what should front caster, camber, toe be?
Seems all of this is connected..given that the rest of suspension is in good shape. Thanks, greasy fingers Nick..near Spokane WA

JeffWhite73

My 73 rear suspension bolts are below the wheel. The ride height looks great, but If I install shorter bolts, will it lift the rear height of the car?

Big2Bird

Yes. The car "hangs" off the bolts via the spring.

JeffWhite73

I'll have to figure something out...they are very close to the tire as well.

lvmyvt76

why add to a 4 year old post, why not start a new post??