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From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
Originally Posted by kodpkd
Putting a plastic spring on a 1977 Corvette is one of the worst things you could do to your 77. OH, unless you are going to race the car. Plastic is way to stiff when you need a bit softer and way to soft when you need stiff. Most cars I see with a composite spring sit way to high in the rear.
What's your reasoning for your statements?
A composite spring is more linear in action and gives a better ride quality than a steel multi-leaf spring. Excellent for both street and track operation.
If the car is sitting too high, it is a simple correction to install slightly longer bolts.
I've been running a composite spring on my 77 since the mid 90's.
Absolutely the best solution for a quality ride and great handling! Hands down a great upgrade.
Just remember to change out shocks to match.
That guy above who thinks composite springs are a bad thing should look at EVERY Corvette made after 1984.
Oh, and NO they don't make your ride height higher.
(which is super easy to adjust anyway).
As per the thickness of the mounting pad. Sorry I'm way to lazy and sore to crawl under my car and measure.
Should be easy to figure out. Put bottom plate on spring. Insert bolt. Measure how much bolt is above spring. Allow about 9/16ths inch of threads. You have your measurement.
Thank you, that’s a really good idea! I also have another 7-leaf laying around so I measured
the thickness of that compared to the composite, which should be enough I just wanted to see if anyone could confirm.
The composite spring measured 1-1/8” thick and the 7 leaf is 2”. So with a 1/2” delrin spacer, the pads should each be 3/16” thick. Considering they are poly, my guess is they may be 1/4” and then compress when everything is bolted together.
What I find odd is the fact Van Steel instructions (with their low arch spring) say to mount the spacer on the bottom. They claim it will give you more ride height adjustability. I guess it will also provide more clearance from the heat coming off the rear exhaust pipes.
It almost seems like that spacer was only used to allow you to re use the original length mounting bolts. If one were to buy shorter mounting bolts (the correct length) the spacer could be eliminated. The composite spring still requires the upper and lower pads however.
Putting a plastic spring on a 1977 Corvette is one of the worst things you could do to your 77. OH, unless you are going to race the car. Plastic is way to stiff when you need a bit softer and way to soft when you need stiff. Most cars I see with a composite spring sit way to high in the rear.
The correct only composite spring to buy is the Van Steel "low arch" rear composite spring. Previous to that it was the Vette Brakes and Products spring. Van Steel bought the tooling/equipment from VB&P and has been making them for some time now.
Most all other manufactures of composite springs will give you a "too bouncy" ride and "too much" ride height. You can choose the spring that suits your driving style. I use a 330lb spring. I have owned my 1980 Corvette since 1983. Three best modifications I have done so far.....composite spring in the rear, composite spring in the front and a spreader bar.
It's important to also note.......if you buy a composite spring then you must buy the appropriate shocks and you must use 8 inch spring end bolts.
A bunch of use "long term" owners will say the same thing.........a rear composite spring is worth it. They are lighter, will last longer and give a slightly better ride and even handle better in the curves.
The correct only composite spring to buy is the Van Steel "low arch" rear composite spring. Previous to that it was the Vette Brakes and Products spring. Van Steel bought the tooling/equipment from VB&P and has been making them for some time now.
Most all other manufactures of composite springs will give you a "too bouncy" ride and "too much" ride height. You can choose the spring that suits your driving style. I use a 330lb spring. I have owned my 1980 Corvette since 1983. Three best modifications I have done so far.....composite spring in the rear, composite spring in the front and a spreader bar.
It's important to also note.......if you buy a composite spring then you must buy the appropriate shocks and you must use 8 inch spring end bolts.
A bunch of use "long term" owners will say the same thing.........a rear composite spring is worth it. They are lighter, will last longer and give a slightly better ride and even handle better in the curves.
Yeah I was pretty fortunate to find a guy near me selling a number of parts, including the Vansteel 360# low arch. He gave me the 8” bolts to go with it and I’ve already ordered my new Bilstein B8’s. Also planning on ordering new strut bars as well, most likely adjustable.
Whichever spring/spacer setup you do. MEASURE THE SPRING MOUNTING BOLTS DEPTH CAREFULLY.
Failure to do so and you could poke a hole into the bottom of the differential housing.
The front two mounting bolts are blind holes, that easily bottom out, right into where the oil lays, inside the diff.
Measure the depth of that hole very carefully. And leave a little extra room after they are tightened.
The diff cracks easily there if they are too tight, and bottom out before they tighten up.
Failure to do so could mean a completely trashed diff.
Did you find the block for your spring? I believe I have a new one if you need it.
Tom
After doing more reading on here, I think I’m going to try shorter bolts rather than a spacer. I bought some 1/8” thick 90A durometer polyurethane that I will use on either side of the spring as the spring isolators.
After doing more reading on here, I think I’m going to try shorter bolts rather than a spacer. I bought some 1/8” thick 90A durometer polyurethane that I will use on either side of the spring as the spring isolators.
Just a thought though. As you see in post 24 the thickness of the steel spring puts the long bottom leaf at a certain distance from the bottom of the diff and the ends of the spring at a certain distance from the tailing arms. The block maintains that distance for the fiberglass spring. I don’t know if is a relevant dimension or not. Just an observation.
Tom
Just a thought though. As you see in post 24 the thickness of the steel spring puts the long bottom leaf at a certain distance from the bottom of the diff and the ends of the spring at a certain distance from the tailing arms. The block maintains that distance for the fiberglass spring. I don’t know if is a relevant dimension or not. Just an observation.
Tom
The installation instructions actually say to install the spacer under the spring, not on top. That’s why I decided to try the shorter bolt option instead.
If it doesn’t work the way I hope, I’ll reach out and see if you still have that spacer. I appreciate the offer and help!
Jake
I believe your on the right track if you do not have a spacer. Proper thin pads and shorter bolts should provide the same end result.
Those instructions are if your useing the stock length bolts,, and 'NEED' a spacer.
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I believe your on the right track if you do not have a spacer. Proper thin pads and shorter bolts should provide the same end result.
Those instructions are if your useing the stock length bolts,, and 'NEED' a spacer.
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