Edzred72

Hi Guys! New "77 owner here. Would someone please give me the pros and cons of steel vre fiberglass rear springs? I am concerned more with longevity than ride characteristics. The cars butt is dragging and she needs a new leaf.
Thanks :cheers:

427V8

Tigger LOVES fiberglass springs, because bouncing is what Tiggers do Best Whoohoohoohooooo!

Real men use steel

But I suppose with the right shock the glass spring could be made to work

Edzred72

What pound rate (315-340-355) was stock in 77?? :cheers:

1LE

Several people I've talked to that have the fiberglass spring say they have a lots of bounce. I have the gymkhana steel spring in mine, and I love it. Nice firm ride, but not too rough.

Stewart's74

When shopping around for a suspension package for my 74 I looked into a glass spring. After speaking with several forum members I went with steel. Seems that the fiberglass springs can break and replacing a rear spring is not what I call fun. Do it once and use steel.

Stew

Tom73

The 'glass spring is more responsive with quicker rebound, thus you need better shocks to control bounce. I have one of each, steel on the L82 and 'glass of the LS4. The LS4 does ride better.

One major problem with the replacement steel spring is correct fit, as in ride height. I have never seen a post here where they were able to get a steel spring that was correct.

tom...

jerryp58

I've heard the pros & cons listed above before. I'm not sure what it takes to break one of the fiber springs, but I have heard that fiber will "hold it's shape" longer than steel.

Another consideration is weight. You drop 40 or 50 lbs when you use the fiber spring.

I don't know the spring rates off hand (I can look them up when I get home if you like), but the 7 leaf spring is the sport version (higher rate) and the 9 leaf is the standard.

FWIW, if I wasn't so cheap, I would have gone for the fiber. If I ever replace the spring again I WILL go with fiber.

Oh, and Welcome :seeya

jerryp58

Jim (1LE), I've got to know; How many miles per gallon do you think you're going to get on that one tank of gas?

I noticed that you 'glassed over your gas door :eek:

71coupe

Steel springs will break too. Just ask me :eek:
Don't the C4 Vette's use the glass spring?

BSeery

Tell that to every C4 owner !! You'll be reall popular.

I like my mono spring, but you do have to have the right shocks for it.

Tom73

The 'glass spring was introduced on the C3 in '81 on automatic and standard suspension Vettes. The 'glass springs have been used ever since, all C4s and C5s have nothing but the composit springs.

tom...

Edzred72

Which shock would you suggest for glass springs? How about Delco Racetek?
KYB?
thanks :cheers:

apple76

I just replaced the rear spring on my 76 last week. Opted for the original 9 leaf steel spring. One reason was cost. You'll fork over another $200 for a glass spring. I'm happy with what I did. The ride is better and the car is sitting level now. One word of advice... no matter what you decide, buy the HD differential cover :yesnod: :yesnod: :yesnod: There's a very good chance the originial cover will break :yesnod: :yesnod: :yesnod:
I'm speaking from experience....

71roadster

I am running the 330lb glass spring that measures about 324lb (its marked on every spring from vette brakes) with the bilstein sport shocks (to avoid the bouncy-ness). I love the spring. Rides and handles great, and like others said, it dropped 40-50 pounds. Aluminum heads up front will balance out that weight loss so the car will still have the same weight balance. The problem I had was that the first spring I was sent had too much arch and I just couldn't adjust the thing enough to get the car to the correct height. From what others said above, it happens with steel springs to (tho steel will settle - fiberglass wont). So nine months later vette brakes sent me a new one (no charge) that is better (tho I would like it to be just a little flatter, but I cope as I only want it about 1/4 -1/2 inch lower) and I used the box and the shipping tag they sent to send the old one back after I made the swap. That way my car was only down for a few hours. I am also running the heavy duty cover. As for breakage, heat may be an issue. I had my exhaust put in after the spring and made sure they gave me as much clearance as necessary. I have seen others use heat wrap around their exhaust in that area.

Easy Mike

Got a friend with an '81 or an 82? They have fiberglass rear springs. Go for a ride and a test drive and compare to your steel spring.

427V8

Really?
I've never heard of anyone getting a glass spring right :rolleyes:

I paid good money for a TRW glass spring because I heard it was the best. I also bought the recommended KYB shocks. After instalation the rear end was about 3" too high. The ride WAS better but if you hit a bump like a railroad track, you'd better DUCK! I felt like a complete moron bouncing around like that. The dealer I bought it from swore that that was the correct ride height and would'nt let me return the spring. They also said I had the best shocks for that spring:mad :mad

I replaced it with a 7 leaf, the ride is a little harsher but not too bad, and best of all the bounce is GONE and the car sits at the correct ride height

1LE

Jeryp58: The door is there, I think is just the angle of the picture. Mileage is not that great. The 74's did not have anything on the top of the gas door like the cross flags or anything. Thats probally why you can't see the door.

terryrudy

Vette Brakes sells specially valved shocks for the fiberglass rear spring. I have the 330lb fiberglass spring from Vette Brakes and some generic gas shocks. Its a little bouncy but wouldn't go back to steel. I also got the extended spring bolts (10") from Vette Brakes that allow me to lower the rear. In the sig pic the rear isn't lowered all the way like it is now. Need to take updated pic. Anyway, I bought the specially valved shocks and will get around to installing them one of these days. Gotta do something about my open headers first.
-terry

LT1driver

I agree, real men are made of steel! I have the 7 leaf, F-41, FE7, Gmykahana whatever you want to call it and love it, only way to go. :D :cool:

ddn

Anyone wanna trade a '68 7-leaf for a 9-leaf? I want the Gymkhana spring.