81 - why monospring or leaf spring?
Team Owner
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From: Southbound
Cruise-In II Veteran
IIRC, in his book, Dave McLellan says they wanted to test the fiberglass spring in a real world situation in prep for the C4. They considered there would be more 81 AT cars than there would be 4 spds. They expanded the test group for 82: all of those have the fiberglass spring.
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Drifting
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From: Chardon Ohio
Drifting
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From: Southlake Texas
St. Jude Donor '16,'24
Melting Slicks
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From: Great Plains Iowa
Le Mans Master
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Burning Brakes
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From: McDonough Georgia
I stand corrected.
Apparently of the 40,000 cars made in 81, 5000 or so were 4 speeds with steel springs.
Seems it might have something to do with the two different assembly plants that year.
In California, however, the 4 speed was illegal and in that state all cars were automatic.
Sorry if i confused anyone.
Apparently of the 40,000 cars made in 81, 5000 or so were 4 speeds with steel springs.
Seems it might have something to do with the two different assembly plants that year.
In California, however, the 4 speed was illegal and in that state all cars were automatic.
Sorry if i confused anyone.
Le Mans Master
Joined: Jul 2004
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Likes: 6
From: Saraland Alabama
St. Jude Donor '11-'12-'13-'14-'15-'16
I have an '81 with automatic and the composite spring. My rear wheels have been squatting and it seems like the suspension bottoms out when I hit a bump so I took it to a tire shop for an alignment this morning.
As soon as they lifted my car they noted that the rear spring was split and said that was causing the bottoming out effect.
I now need to buy a new rear spring for the '81 so I have a few questions as my car is NCRS Top Flight and I want to keep it original as much as possible. The car only has 46k original miles.
Where should I buy one?
What is a fair price?
Are there other parts I should replace while replacing the rear spring?
How difficult is the replacement of the rear spring? I consider myself a fair to decent mechanic but would not attempt an engine or transmission rebuild. I have a heated basement garage and most kinds of tools.
What would be a fair charge if I hire a garage to replace the spring?
As soon as they lifted my car they noted that the rear spring was split and said that was causing the bottoming out effect.
I now need to buy a new rear spring for the '81 so I have a few questions as my car is NCRS Top Flight and I want to keep it original as much as possible. The car only has 46k original miles.
Where should I buy one?
What is a fair price?
Are there other parts I should replace while replacing the rear spring?
How difficult is the replacement of the rear spring? I consider myself a fair to decent mechanic but would not attempt an engine or transmission rebuild. I have a heated basement garage and most kinds of tools.
What would be a fair charge if I hire a garage to replace the spring?
Last edited by FLACHUSNRET; Jan 29, 2016 at 01:50 PM.
Drifting
Joined: Jan 2012
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From: Fredericksburg Virginia
If you have ANY mechanical inclination, a few sockets, a floor jack, and 2 (preferably 4) jackstands, then replacing the rear leaf spring is easy.
We're talking about 4 bolts in the middle and 1 bolt at each end. That's it.
I would replace the rubber at the ends of the spring when replacing.
The new spring SHOULD come with new rubber for the center. If it doesn't, then get that kit too.
Be sure not to over-tighten the center when reinstalling. Really, you're just talking about holding the spring in place...to keep it from flopping around. The weight of the car will do 90% of the work.
For me, this is a 1 hour job. More time is spent getting the car up and the wheels off than the actual act of tinkering with the spring.
We're talking about 4 bolts in the middle and 1 bolt at each end. That's it.
I would replace the rubber at the ends of the spring when replacing.
The new spring SHOULD come with new rubber for the center. If it doesn't, then get that kit too.
Be sure not to over-tighten the center when reinstalling. Really, you're just talking about holding the spring in place...to keep it from flopping around. The weight of the car will do 90% of the work.
For me, this is a 1 hour job. More time is spent getting the car up and the wheels off than the actual act of tinkering with the spring.
Le Mans Master
Joined: Jul 2004
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From: Saraland Alabama
St. Jude Donor '11-'12-'13-'14-'15-'16
Thanks for the great info.
I looked at Mid-America's website and the cost of a fiberglass spring is $319.99--Just a wee bit pricey!
Any other sources I should check?
I looked at Mid-America's website and the cost of a fiberglass spring is $319.99--Just a wee bit pricey!
Any other sources I should check?
Drifting
Joined: Jan 2016
Posts: 1,589
Likes: 4
From: Southlake Texas
St. Jude Donor '16,'24
I stand corrected.
Apparently of the 40,000 cars made in 81, 5000 or so were 4 speeds with steel springs.
Seems it might have something to do with the two different assembly plants that year.
In California, however, the 4 speed was illegal and in that state all cars were automatic.
Sorry if i confused anyone.
Apparently of the 40,000 cars made in 81, 5000 or so were 4 speeds with steel springs.
Seems it might have something to do with the two different assembly plants that year.
In California, however, the 4 speed was illegal and in that state all cars were automatic.
Sorry if i confused anyone.
One other bit a trivia, '81s ordered with autos and Gymkhana suspension got the steel spring. (At least that's how I interpret the Black Book) Mine was a 4-speed, with Gymkhana, so I know it had a steel spring.
Drifting
Joined: Jan 2012
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From: Fredericksburg Virginia
This may be one of those situations where NRCS-type parts get you the points, but aftermarket components are considerably 'better' than stock.
Gonna have to make a choice, it seems.
Gonna have to make a choice, it seems.
Le Mans Master
Joined: Jul 2004
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From: Saraland Alabama
St. Jude Donor '11-'12-'13-'14-'15-'16
I see the 192 Lb. and 300 Lb. and the various other ratings on the springs.
What exactly or how is this rating determined? Obviously the higher the rating the stiffer the spring will be, but how do they determine those numbers?
What exactly or how is this rating determined? Obviously the higher the rating the stiffer the spring will be, but how do they determine those numbers?
Le Mans Master
Joined: Jul 2004
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From: Saraland Alabama
St. Jude Donor '11-'12-'13-'14-'15-'16
Can anyone tell me for sure that they are interchangeable without cutting/welding? I am a fairly good mechanic when replacing bolt-on items but do not do cutting and welding.
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Drifting
Joined: Dec 2011
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From: Chardon Ohio
This is the first I have heard that the stock composite springs are 'soft' and it might be better to look at either a stiffer composite spring or going with a leaf spring. Is this generally true?
Drifting
Joined: Jan 2012
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From: Fredericksburg Virginia
I do not believe there are any modifications required to go between fiberglass and steel springs. At worst you'll need longer bolts if there isn't a 'make up block' in the current fiberglass spring stack where it is held onto the center section.