Notices
C1 & C2 Corvettes General C1 Corvette & C2 Corvette Discussion, Technical Info, Performance Upgrades, Project Builds, Restorations
Sponsored by:
Sponsored by:

fiberglass rear leaf spring

 
Old 02-21-2017, 05:50 PM
  #1  
pewter-FRC
CF Senior Member
Thread Starter
 
pewter-FRC's Avatar
 
Member Since: Sep 2009
Location: Pittsburgh PA
Posts: 4,726
Received 10 Likes on 10 Posts
Default fiberglass rear leaf spring

does the car ride any better with one of these? my 66 rides like a bucket of poop with the steel leaf
pewter-FRC is offline  
Old 02-21-2017, 06:56 PM
  #2  
rtruman
CF Senior Member
 
rtruman's Avatar
 
Member Since: Dec 2009
Posts: 3,922
Received 197 Likes on 170 Posts
Default

Put one in my 63 was a lot better
rtruman is offline  
Old 02-21-2017, 07:03 PM
  #3  
DUB
CF Senior Member
 
Member Since: Apr 2009
Location: Charlotte NC
Posts: 19,674
Received 2,521 Likes on 2,187 Posts
Default

YES...they can ride much better....depending on the spring rate.

And keep in mind any excessive radiant heat from exhaust pipes can effect the composition of the spring material....so possibly wrapping up the pipe slightly before the spring area and after can aid in its life expectancy.

You can contact Gary at Vette Brakes and Products and he can explain it if you need a second source of validation.

DUB
DUB is offline  
Old 02-21-2017, 07:03 PM
  #4  
Bluestripe67
CF Senior Member
Support Corvetteforum!
 
Bluestripe67's Avatar
 
Member Since: Jan 2002
Location: Close to DC
Posts: 11,504
Received 583 Likes on 535 Posts
Default

A combination of good gas shocks that are designed to work with the composite spring can result in a better ride. Dennis
Bluestripe67 is online now  
The following users liked this post:
jerry gollnick (02-22-2017)
Old 02-21-2017, 08:25 PM
  #5  
pewter-FRC
CF Senior Member
Thread Starter
 
pewter-FRC's Avatar
 
Member Since: Sep 2009
Location: Pittsburgh PA
Posts: 4,726
Received 10 Likes on 10 Posts
Default

thanks guys. it has a good set of gas shocks all the way around. i already have a slightly used fiberglass spring. i will have to give it a try

Last edited by pewter-FRC; 02-21-2017 at 08:26 PM.
pewter-FRC is offline  
Old 02-22-2017, 04:01 AM
  #6  
alexandervdr
CF Senior Member
 
Member Since: Jul 2011
Location: Bornem
Posts: 1,965
Received 92 Likes on 68 Posts
Default

Define 'better'? A new leaf spring is better than an old and tired one too A correct balance between spring and dampers and car has probably more impact on 'better' than just looking for the best composite spring
alexandervdr is offline  
Old 02-23-2017, 10:16 AM
  #7  
66BlkBB
CF Senior Member
 
66BlkBB's Avatar
 
Member Since: Oct 2004
Location: Northern MN
Posts: 3,285
Received 44 Likes on 35 Posts
St. Jude Donor '13-'14-'15-'16-'17
Default

I had one on a 72 coupe that I owned. Did not like it. I believe it was the 300 lb unit and it rode stiff. My 66 with the 9 leaf spring rides great. I wouldn't even think about installing a composite unit in it. JMO
66BlkBB is offline  
Old 02-23-2017, 10:34 AM
  #8  
vettebuyer6369
Moderator
 
vettebuyer6369's Avatar
 
Member Since: Jul 2000
Location: About 1100 miles from where I call home. Blue lives matter.
Posts: 38,946
Received 1,806 Likes on 1,102 Posts
Default

Originally Posted by rtruman View Post
Put one in my 63 was a lot better


I put one in my 63 and my 69.

Clear improvement.
vettebuyer6369 is offline  
Old 02-23-2017, 12:28 PM
  #9  
DSR
CF Senior Member
 
Member Since: Jun 2006
Location: Durham ON
Posts: 980
Received 34 Likes on 30 Posts
Default

Originally Posted by 66BlkBB View Post
I had one on a 72 coupe that I owned. Did not like it. I believe it was the 300 lb unit and it rode stiff. My 66 with the 9 leaf spring rides great. I wouldn't even think about installing a composite unit in it. JMO
I had the same thing. Very stiff ride. I took it out 5000 miles later and put a new stock spring in. Much better! The stiffer springs maybe good for racing, not so good for street use. I went for stock a spring, large sway bars, good shocks and tires. Makes for a comfortable riding street car.
DSR is offline  
Old 02-23-2017, 12:39 PM
  #10  
Mike67nv
CF Senior Member
 
Mike67nv's Avatar
 
Member Since: Apr 2010
Location: Northern Nevada
Posts: 2,029
Received 217 Likes on 160 Posts
2018 C2 of Year Finalist
2015 C2 of the Year Finalist
Default

I posted this is a similar thread six months ago or so, but it's still my opinion.

A monoleaf composite spring has no interleaf friction, like a multi-leaf steel spring, and requires shocks with a much higher level of damping (rebound and compression). Stock type shocks won’t do the job and you’ll have a “bounce” problem. So, without getting into spring rates and ride quality, unless you can get shocks “engineered” for a specific composite spring, I would stay away from one.

In my opinion, Chevrolet did a pretty good job engineering the 2 stage (6/3) spring in the midyear Corvette. If you’re serious about replacing a steel spring, I would give Eaton Detroit Spring a call – their springs are about as close to original as you will find.

Last edited by Mike67nv; 02-23-2017 at 12:39 PM.
Mike67nv is offline  
Old 02-23-2017, 05:01 PM
  #11  
Frankie the Fink
CF Senior Member
Support Corvetteforum!
 
Frankie the Fink's Avatar
 
Member Since: Aug 2007
Location: Orlando Metro Area Florida
Posts: 49,977
Received 4,017 Likes on 3,086 Posts
Default

Originally Posted by Mike67nv View Post
I posted this is a similar thread six months ago or so, but it's still my opinion.

A monoleaf composite spring has no interleaf friction, like a multi-leaf steel spring, and requires shocks with a much higher level of damping (rebound and compression). Stock type shocks won’t do the job and you’ll have a “bounce” problem. So, without getting into spring rates and ride quality, unless you can get shocks “engineered” for a specific composite spring, I would stay away from one.

In my opinion, Chevrolet did a pretty good job engineering the 2 stage (6/3) spring in the midyear Corvette. If you’re serious about replacing a steel spring, I would give Eaton Detroit Spring a call – their springs are about as close to original as you will find.
I also wonder how much "improvement" you get with this sort of thing. I put AC Delco shocks on my 63 with the original springs and it rides wonderfully.
Frankie the Fink is offline  
Old 02-23-2017, 07:23 PM
  #12  
rtruman
CF Senior Member
 
rtruman's Avatar
 
Member Since: Dec 2009
Posts: 3,922
Received 197 Likes on 170 Posts
Default

Originally Posted by Mike67nv View Post
I posted this is a similar thread six months ago or so, but it's still my opinion.

A monoleaf composite spring has no interleaf friction, like a multi-leaf steel spring, and requires shocks with a much higher level of damping (rebound and compression). Stock type shocks won’t do the job and you’ll have a “bounce” problem. So, without getting into spring rates and ride quality, unless you can get shocks “engineered” for a specific composite spring, I would stay away from one.

In my opinion, Chevrolet did a pretty good job engineering the 2 stage (6/3) spring in the midyear Corvette. If you’re serious about replacing a steel spring, I would give Eaton Detroit Spring a call – their springs are about as close to original as you will find.
They didn't have the fiber glass spring back then just my opinion
my 63 handled better maybe my shocks were bad .
It felt better maybe the original was fatigued
rtruman is offline  
Old 02-23-2017, 10:13 PM
  #13  
63split63
CF Senior Member
 
63split63's Avatar
 
Member Since: Mar 2005
Location: Ontario
Posts: 1,222
Received 27 Likes on 25 Posts
Default I like Fiberglass

I have fiberglass rear springs on my 66 BB and 71 LT1 . I like them .
63split63 is offline  
Old 02-24-2017, 07:57 AM
  #14  
bluestreak63
CF Senior Member
 
bluestreak63's Avatar
 
Member Since: Mar 2003
Location: Philadelphia PA
Posts: 3,847
Received 94 Likes on 58 Posts
Default

Originally Posted by Frankie the Fink View Post
I also wonder how much "improvement" you get with this sort of thing. I put AC Delco shocks on my 63 with the original springs and it rides wonderfully.
FTF, what ac delco shocks did you use? Do you have a part number? While working on the brakes, there's gonna be some scope creep. The shocks that are on now have seen better days and the bushings are shot.

What was oem on these back in the day, ac delco?
bluestreak63 is offline  
Old 02-24-2017, 12:07 PM
  #15  
johngandersonjr
CF Senior Member
 
johngandersonjr's Avatar
 
Member Since: Jan 2007
Location: Hilbert WI
Posts: 447
Received 14 Likes on 13 Posts
Default

Yes. I replaced my sagging spring with a fiberglass mono leaf along with more stout shocks. I used the stock shocks at first and it bounced all over.

Mono leaf is not supposed to sag over time either.
johngandersonjr is offline  
Old 02-24-2017, 12:29 PM
  #16  
Frankie the Fink
CF Senior Member
Support Corvetteforum!
 
Frankie the Fink's Avatar
 
Member Since: Aug 2007
Location: Orlando Metro Area Florida
Posts: 49,977
Received 4,017 Likes on 3,086 Posts
Default

Originally Posted by bluestreak63 View Post
FTF, what ac delco shocks did you use? Do you have a part number? While working on the brakes, there's gonna be some scope creep. The shocks that are on now have seen better days and the bushings are shot.

What was oem on these back in the day, ac delco?
Yes AC-Delco were originally from the factory, I replaced my Monroe Gas-Ajust with AC-Delco modern equivalents to get some judging points for having at least the correct brand and they turned out to be nice shocks... I'd have to dig through my receipts to find the actual part numbers....I think I might have just gone to NAPA and had them look them up for the 63.
Frankie the Fink is offline  
The following users liked this post:
bluestreak63 (03-03-2017)
Old 02-24-2017, 12:56 PM
  #17  
MelWff
CF Senior Member
 
MelWff's Avatar
 
Member Since: May 2006
Location: Danbury CT
Posts: 10,702
Received 668 Likes on 641 Posts
Default Spring

Originally Posted by pewter-FRC View Post
does the car ride any better with one of these? my 66 rides like a bucket of poop with the steel leaf
Just to make sure you dont have other issues:
1. What cold tire pressure are you running?
2. Are your tires more than 10 years old?
MelWff is offline  
Old 02-24-2017, 01:37 PM
  #18  
ganshert
CF Senior Member
 
ganshert's Avatar
 
Member Since: Nov 2013
Location: Colorado
Posts: 343
Received 67 Likes on 46 Posts
Default

Some interesting info on the subject from an online vendor that sells both steel and composite springs.

"Composite vs. Steel Rear Leaf Springs

A couple of times a week we are asked to give the plusses and minuses of composite vs. steel rear leaf springs. This is how we see it:

The TRW spring is the OEM replacement spring for the 81 and 82 Corvette. From 1963-1980, Corvettes came with steel rear leaf springs. In an effort to shave weight off the car to help with fuel economy, for the 1981 model year Chevrolet went with magnesium valve covers, a composite rear spring and a number of other weight saving substitutions. The spring change saved about 20 lbs; a huge savings for comparatively little money. To the end user, the twenty pounds is equivalent to about two and a half gallons of gas; not exactly earth shaking for the average Corvette driver.

Unfortunately the composite spring weight savings was right where the Corvette least needed to lose weight; low and behind the rear axle. The steel spring is like ballast in a racecar, right where it needs to be; low and behind the rear axle.

Composite springs don’t lose their spring rate over time. A 315 lb spring will stay 315 lbs until it breaks. Yes, that’s what sends composite springs to the dumpster; a rock in just the right place. Hit on edge by a road hazard, a composite spring will often de-laminate. It will turn a milky white at the point of injury and its service life is over. A steel spring will slowly lose its spring rate over time, but it will never break.

The softest TRW composite spring is 315 lbs. Most C2 and C3 Corvettes came with 196 lb. steel rear springs. After 20 years or so, when they are ready for replacement, their effective spring rate has eroded by as much as 40%. Replacing the original spring with a new stock steel spring makes a big difference; a 40% difference. Changing to a 315 lb spring would be a change of 270%, and you would have a completely different automobile.

The spring rate of the 78-80 OEM factory steel rear spring was 260 lbs. You can order a 315 lb spring for a 78-79, but for anything newer than that, you have to chose between 345 and 355 lbs. That’s a heavier spring rate than we run on our racecars, so you can imagine it’s not the softest ride on the planet.

One more thing that may or may not be a big deal to a street driven Corvette: The steel spring is at least somewhat progressive in its spring rate. In our custom steel springs that we use for our racecars, we individually arch every leaf to achieve an almost linier rate progression. This helps handling a lot, and we see it in our lap times. Obviously that’s not possible with a composite spring.

In summary:

Composite spring Advantages:

• Light weight
• Permanent spring rate

Disadvantages:

• Cost
• Durability
• Limited spring rate options
• Often much stiffer than stock"
ganshert is offline  
The following 2 users liked this post by ganshert:
colo63sw (03-03-2017), Frankie the Fink (02-25-2017)
Old 02-24-2017, 04:37 PM
  #19  
65 vette dude
CF Senior Member
 
65 vette dude's Avatar
 
Member Since: May 2007
Location: cooper city florida
Posts: 3,461
Received 12 Likes on 12 Posts
Default

Originally Posted by bluestreak63 View Post
FTF, what ac delco shocks did you use? Do you have a part number? While working on the brakes, there's gonna be some scope creep. The shocks that are on now have seen better days and the bushings are shot.

What was oem on these back in the day, ac delco?
Last I heard, Gabriel makes Delco shocks. I have Delco Professional on my 65, and I like them very much. Gabriel Ultra gas shocks are suppose to be the same as the Delco Professionals. Rock Auto sells both brands for a C2 at about 20 dollars a piece.
65 vette dude is offline  
Old 03-02-2017, 09:37 PM
  #20  
Garette
Junior Member
 
Garette's Avatar
 
Member Since: Mar 2017
Posts: 8
Likes: 0
Received 0 Likes on 0 Posts
Default

In a few days i will be replacing my steel with composite, how would i know what shocks to get?
Garette is offline  

Thread Tools
Search this Thread
Quick Reply: fiberglass rear leaf spring


Contact Us - About Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: