Check my thinking

So, one of the last things to do on the duster is finish up the slider mounts. I figure that springs probably ought to be mounted before driving it.

Anyway, I'm using speedway sliders, and 4x4 1/4 wall square tubing. Looks like this.

[URL=http://s54.photobucket.com/user/dusterbd13/media/Mobile%20Uploads/2016-08/20160829_072249_zpsb8gasibr.jpg.html][/URL]

I'm debating how to finish it. Easiest way would be to use 3/8 bolts through the trunk floor to square tube, and 1/4 through the slider and tube.

This would leave the last inch of the slider unsupported and hanging in space.

Other part of me wants to bolt through the trunk floor and slider, but notch the tube to fit against the frame and bolts to the original shackle location as well.

I'm pretty sure either way will work just fine, but want yall's opinions and experience. This is primarily a street car, with autocross or hpde as a lark on occasion.

So, by the lack of discussion, I'm either good either way I go, or on the lunatic fringe. And I know this crowd, and this is nowhere near the lunatic fringe.

I know nothing about spring sliders!

dculberson wrote: I know nothing about spring sliders!

I thought we were talking seat-rail sliders at first. Is this some kind of old-school hotrod sorcery?

More Circle track sorcery. Replaces the rear shackle with a slider to free up movement and reduce leaf spring rate changes due to geometry changes.

I'm more worried about structural integrity than anything else at this point. With the 4x4 in there, I can easily go back to stock if needed. But only if I don't do any welding.

I've only ever seen them attached to a frame rail. What's the chunk of 4x4 attached to? Just sitting under the trunk floor?

Currently it's only held in by gravity and friction.

Plan was to mount to trunk floor, or mount to factory shackle location on rail and trunk floor.

When the slider reaches that point way back the springs will be under max load so yes I'd want the support to avoid bending the slider. I'd have some 1/8 plate bent up to fit over the stock frame rail and go 1-2 inches from the slider drill two 3/4 hole straight thru the frame rails then weld in some 3/4 x 1/2 tubing (AA-mfg.com) in the holes so you can cross bolt without crushing the frame. This would be removable and leave the stock shackle mounts there. If you have a local race shop they might have the 3/4 x1/2 tubing in stock as well cause most use it for steering collums.

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