Shortened Rear Monospring

I'm about to order a rear monospring (360 pounds/inch). I have off set trailing arms. I know the spindle linkage attach point geometry is unaffected by offset trailing arms, however with offset trailing arms you can install wider tires that get close to were the spring attachs to the spindle fork. So if I ask for the spring to be shortened, should I ask for 1/2 inch or 1 inch (per sied), or what? Any experience? Thanks

There is a "double offset" trailing arm for C3's where the arm and the spring mount are moved to the inside. These require a shortened spring. I believe the springs are shortened 1" per side.

I've wondered about this as well. Shortening it an inch would cut the hole in half (for the bolt).... so can you drill a new hole in the spring? I suspect it's possible, but I wonder if anyone else has done it (before I ruin a relatively expensive spring)...

SuperBuickGuy said:

I've wondered about this as well. Shortening it an inch would cut the hole in half (for the bolt).... so can you drill a new hole in the spring? I suspect it's possible, but I wonder if anyone else has done it (before I ruin a relatively expensive spring)...

Click to expand...

FROM what I have READ, they say the spring will delaminate and split lengthwise,


BUT, in all those comments, no one ever said anything about using some glue like maybe JB weld.....it's a surmise on my part, nothing more....

I dunno jack shit about the dual mount springs, mine is a 360 single/center mount, and I use the supplied 8" bolts, no sweat on my 17x9.5" wheels which kept the same centerline as stock/close as possible...I never altered the spring, I have 275/50/17 in rear now....

:drink:

I just ordered a 360 lb/inch spring from VBP. I ordered a spring reduced in length by 1/2 inch from each end. I assume they have springs in inventory that are still "blank" on the ends, so they can be cut for reduction and then drilled for the mounting bolt. I've heard that some people order them reduced in length by 1 inch at each end. I looked at the geometry of the spring on my 68, it's been reduced in length by 1/2 inch also, and I think 1 inch would not be a good idea. With a 1/2 inch reduction in spring length, you can see that the spring to trailing attach bolt is not exactly vertical to the ground, since it has to be tilted slightly to match up with the spring hole. I kinda think it wasn't necessary to have the spring shortened. The spring end on the 68 nearest approach to the wheel has it facing the metal of the wheel. No chance of spearing the tire. I think where you really need to shorten the spring is if you are using long spring to trailing arm bolts so that the spring end approaches the tire sidewall....then there's a danger of the sidewall balloooning out on a bump and then being speared by the spring end.

......Just for curiosity, I installed 10 inch bolts to attach the trailing arm to the spring on my 68. It dropped the rear end down really low, but the spring end was dangerously close to the road and the sidewall. I went back to a shorter bolt, I think it was 8 inches....I could easyily check. The stock length bolt is 6 inches I think.