leaf spring info.
Thread Starter
Heel & Toe
Joined: Nov 2013
Posts: 20
Likes: 0
From: Northern Minnesota
leaf spring info.
I am looking for some help with c4 leaf springs.
They have 3 letters engraved on them (BMB,HMJ,HKX,ect.)
My question is the spring rate of these are all different.
Are the larger numbered spring rates stiffer springs or softer.
Thanks for your help.
They have 3 letters engraved on them (BMB,HMJ,HKX,ect.)
My question is the spring rate of these are all different.
Are the larger numbered spring rates stiffer springs or softer.
Thanks for your help.
Safety Car
Joined: Jan 2004
Posts: 3,556
Likes: 12
Yes , in most cases
No relevance.
the rate varies by year and what suspension pkg it was installed with
Put up what you have and someone will tell you the rate
the rate varies by year and what suspension pkg it was installed with
Put up what you have and someone will tell you the rate
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Here's a chart with the spring rates for various years. Unfortunately it doesn't have the "secret code" letters for the springs. My recollection is that mine has a small metal tag with the letters stamped on it.:
http://corvetteactioncenter.com/tech...l#.Uos_aqX5Frc
http://corvetteactioncenter.com/tech...l#.Uos_aqX5Frc
Team Owner
Joined: Sep 2003
Posts: 25,330
Likes: 2,722
Safety Car
Joined: Jan 2004
Posts: 3,556
Likes: 12
Instructor
Joined: Sep 2012
Posts: 204
Likes: 3
From: Bristol Rhode Island
aligned/w this thread,would there be negative consequences to installing a stiffer front spring than the FE1 softride spring originally installed on the front of an '89?
Or is there a benefit to the consumer hoping for a better sporting ride? In conjunction/w new Bilsteins,bushes,and ball joints?
Or is there a benefit to the consumer hoping for a better sporting ride? In conjunction/w new Bilsteins,bushes,and ball joints?
Thread Starter
Heel & Toe
Joined: Nov 2013
Posts: 20
Likes: 0
From: Northern Minnesota
Thanks to all that replied.
My problem is the 86-87 FE1 suspension that came with the kit
did not come with leaf springs, so i am trying to find some that
will not be real stiff like some vette's i have been in.
The car will weigh about 1800 lbs and be mostly street driven.
(a little road course driving)
Thanks for the help.
My problem is the 86-87 FE1 suspension that came with the kit
did not come with leaf springs, so i am trying to find some that
will not be real stiff like some vette's i have been in.
The car will weigh about 1800 lbs and be mostly street driven.
(a little road course driving)
Thanks for the help.
Team Owner
Joined: Sep 2003
Posts: 25,330
Likes: 2,722
aligned/w this thread,would there be negative consequences to installing a stiffer front spring than the FE1 softride spring originally installed on the front of an '89?
Or is there a benefit to the consumer hoping for a better sporting ride? In conjunction/w new Bilsteins,bushes,and ball joints?
Or is there a benefit to the consumer hoping for a better sporting ride? In conjunction/w new Bilsteins,bushes,and ball joints?
You really need to check the spring code of what you have. In '89 I believe the only thing that changed the front spring was FX3, FE1 & FE7 were the same. Quite sure. Now an after-market "sport" option could be considered and the game changes. There's even an adjustable one for the front.
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Team Owner
Joined: Sep 2003
Posts: 25,330
Likes: 2,722
Thanks to all that replied.
My problem is the 86-87 FE1 suspension that came with the kit
did not come with leaf springs, so i am trying to find some that
will not be real stiff like some vette's i have been in.
The car will weigh about 1800 lbs and be mostly street driven.
(a little road course driving)
Thanks for the help.
My problem is the 86-87 FE1 suspension that came with the kit
did not come with leaf springs, so i am trying to find some that
will not be real stiff like some vette's i have been in.
The car will weigh about 1800 lbs and be mostly street driven.
(a little road course driving)
Thanks for the help.
What is the build? Many times the C4 control arms, rack etc are used but there's no provision for using the C4 leaf. The '87 and earlier requires more parts than the later to use the leaf. What exactly I guess do you have?
Thread Starter
Heel & Toe
Joined: Nov 2013
Posts: 20
Likes: 0
From: Northern Minnesota
As I said, I do not have the springs so i can not measure them.
I have the front suspension (minus the springs) Welded to a tube chassis(jig built)
and a rear end(minus springs) that mounts to the chassis.
I have the front suspension (minus the springs) Welded to a tube chassis(jig built)
and a rear end(minus springs) that mounts to the chassis.
Team Owner
Joined: Sep 2003
Posts: 25,330
Likes: 2,722
On the rear of the build you can use any year C4 spring - '84 - '96!
Instructor
Joined: Apr 2007
Posts: 225
Likes: 1
From: Highland Village texas
Since your looking for the lowest matched spring rates front and rear. you will want to get as close to the 96 non z51 coupe c4 spring rate specs as possible as they are known for their good ride with 26mm front sway bar and 24mm rear sway bar. the 96 spring rate is 60nm front and 26nm rear. Since you have a 87 and earlier front suspension what you will need to go for is the 54.4nm HMN code front spring available on 86,87 convertibles. If this spring cant be found the 54.0 nm HKX used on some 85 base suspension coupes. Next is the lightest spring rate its 51.8nm HMP used on 85-87 base suspension coupes. In the rear you will want the 26nm RHZ used from 94-96. If your running the lowest spring front rate listed maybe run a larger front swaybar and you will be very close to how a 96 drives.
Team Owner
Joined: Sep 2003
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