Gas Struts on The trunk lid? Here you go.
About to embark on a gas strut conversion on my 67 Dart convertible. Been a long time coming. Had been hoping to find someone that can recondition the torsion rods but no luck there. The last straw was buying a set of used rods that also turned out to be mushy then finding I had some torn metal on the mounts as well. I'm kind of over torsion rods at this point!
So here we go. Maybe you guys can check me for sanity on this. I haven't done it yet but I just put in the order for the struts - 15"/67lbs each side so 134lbs total. Came to this by doing a little math. Trunk weight at the outer edge where the key is comes in at about 35 pounds which is about 38" from the pivot point. Looks like I'll have the rod mount at about 8" off the pivot point so it looks like that's about 160lbs. The plan is to have the strut rods assisted by the mushy torsion bars so I'm going to try this out. Worst case weight-wise is that I'll waste the $14 on the set of struts I just ordered.
The rods I ordered:
https://www.amazon.com/gp/product/B01M9FWIV6/?tag=fabo03-20
So with the top folded down and some obstructions the first this I was concerned about is the routing and extension needed to have the rods as out of the way as possible. So I made a little jig with some magnets and a coat hanger. Marked the coat hanger off at the 14.96" extended and 9.06 compressed points then put the one magnet on the hopeful hinge mount point and set the other one down by the wheel tub right at the extended point on the rod. Then close the trunk and see if the hanger pushes past the compressed point. It didn't. Maybe an eighth of an inch to spare!
Not a lot of room with the top lowered, the gas fill tube and there is a triangle of space cause by the support bracket.
Anchor point on the hing just under the original rod.
Man that is close. The white marks are extended and compressed lengths in relation to the hinge mount point. This is the trunk in the closed position as seen from the seat area with seats removed.
Had also considered going from the trunk lid to the hinge bracket. Would have been a no-brainer extension-wise and could have used lighter struts but this is a daily driver and I do put my bicycle in trunk hidden away fairly often so I thought I'd try the more hidden method.
So the plan is to have the hinge mount point just under where the original rod and slider meet. Want to make sure that they don't interfere with each other but can't afford to come too far off the hinge without getting a rod with more extension. So far it looks like it will work.
Going to make some 1/8" flat bar steel brackets that bolt on to the hinge with a hole for the strut. Make one, re-test the extension then make another bracket for the lower end that will mount to the floor just next to the wheel tub with holes drilled in the floor and stainless steel hardware. Floor seems like much thicker gauge steel than the wheel tub so I'm going to trust that to the 67 pounds of force that's coming. Will connect the rod to that bracket, mark off the hole positioning on the floor, drill that and attach bracket to the floor. Going to make the floor bracket a little long in case I need to get a longer strut and drill a new hole in it rather than a whole new bracket. Next do a little trunk close and open test to make sure nothing unexpected is happening then do the other side. Once they are in and working I'll maybe add the original torsion rods back to help, leave it as-is or buy some different weight shocks depending on how it goes weight-wise. Seems like there are several weights available in the 15" struts that have the same extended and compressed lengths.
Am I missing anything?