Question Regarding VBP Springs
Thread Starter
Instructor
Joined: Feb 2007
Posts: 114
Likes: 18
From: McKinney TX
Question Regarding VBP Springs
I decided to replace the nine leaf metal spring with a VBP composite so I ordered a 360 pound spring complete with hardware for my '74. I discovered to my surprise that my differential cover is from a '78-79. Sure enough, the metal spring was 2 1/2 inches wide while the new composite was 2 1/4.
I ordered a new VBP spring for the '78-79 cover, again with hardware. To my surprise this time, I found the spring to be identical to the one I already had; only the hardware was different. (Smaller bolts.) I called VBP and they confirmed that all springs are the same width, only the hardware changes.
VBP states that the mounting plate should be torqued to 40-45 ft-lb. I found that the plate they provided became severely distorted even at 32 ft-lb.
My question to you who have done this install: Is this plate distortion normal on the earlier 2 1/4 wide differential cover? Have you seen it on the 2 1/2 inch cover? Finally, if you did experience plate distortion, did you torque the plate all the way to 40-45 ft-lb or did you leave it at a lesser value?
I ordered a new VBP spring for the '78-79 cover, again with hardware. To my surprise this time, I found the spring to be identical to the one I already had; only the hardware was different. (Smaller bolts.) I called VBP and they confirmed that all springs are the same width, only the hardware changes.
VBP states that the mounting plate should be torqued to 40-45 ft-lb. I found that the plate they provided became severely distorted even at 32 ft-lb.
My question to you who have done this install: Is this plate distortion normal on the earlier 2 1/4 wide differential cover? Have you seen it on the 2 1/2 inch cover? Finally, if you did experience plate distortion, did you torque the plate all the way to 40-45 ft-lb or did you leave it at a lesser value?
Thread Starter
Instructor
Joined: Feb 2007
Posts: 114
Likes: 18
From: McKinney TX
I've read various threads on this forum regarding broken composite springs so I was very careful to center the spring correctly and to torque it only after the car was placed on the ground.
The fact that I'm putting a 2 1/4 wide spring in a 2 1/2 wide 'slot' bothers me. (I use the word 'slot' to represent the distance between the mounting bolts.) There's nothing to prevent the spring from being slightly off from the exact perpendicular to the direction of the car. I don't know if that could introduce stresses that led to the many broken springs written in various posts on this forum.
The fact that I'm putting a 2 1/4 wide spring in a 2 1/2 wide 'slot' bothers me. (I use the word 'slot' to represent the distance between the mounting bolts.) There's nothing to prevent the spring from being slightly off from the exact perpendicular to the direction of the car. I don't know if that could introduce stresses that led to the many broken springs written in various posts on this forum.
Drifting
Joined: Oct 2004
Posts: 1,259
Likes: 7
From: Ontario
also agree! I did not like the extra space in mine. I used some 1/8" aluminum and made a spacer plate for each side of the spring. I recall that you can buy spacer plates for this issue from other major vette suppliers(Ecklers 36914). I am surprised that VBP would not be recomending this and including the spacers with 78+ springs. I do not feel that the spring gap along with the possibility of it being off center would change the alignment or performance of the rear suspension...but I did not like the idea that it could move around under there.
Last edited by Retro78; Jul 15, 2007 at 10:30 AM.
