I've got a '93 fullsize blazer that I'm starting to do a low-dollar rear end build on. I'm pretty comfortable with designing my own hangers for a home brew shackle flip in the rear, but as far as locating where to install it for proper shackle angle at ride height, I'm lost. Is there a way to determine loaded leaf length without doing something too shady involving lowering the vehicle weight onto the springs with a floor jack, wood, etc. etc? I'm not trying to die underneath this thing, and it's on an angled driveway. I can do the math to get the angles right even on a non-level driveway, but I'm considering using different springs from the stockers (2500 take off springs with a leaf removed, different length and rate), which is why I'd need a loaded length from eye to eye to get the angle right on the shackle. If it was just a question of the stock length, I'd go put a tape measure under a local stock 2dr tahoe or blazer. I think, even though it may make it a bit bouncier, the 2500 springs are longer, and with the helper spring removed, would prolly ride decently under the ass end of this heavy pig. Oh, and the springs would def work with my 2500hd 14bff :flipoff2:. Found a local set for cheap, that's why I'm asking about this.



thanks...

edit... I recall seeing something in some post somewhere (=P) where dude said he lowered the vehicle weight on to the leaf and measured... This is kind out of my capability in my current situation, seeing as I need my limbs intact to continue earning funds for this project, no matter how low dollar it is. =P

I would run a set of 64"s....in the rear....plenty flexy, and found in 88-98 GM 1/2 and 3/4 tons.


But on to your question:

Install the front end of the springs. Bolt the springs to the axle.

Assemble your shackle flip brackets, shackle hangers to the rear end of the springs. A frame lift works the best for this IMHO....

And get yourself a magnetic angle finder if you don't have one.

Now, you are going to want to achieve (these angles worked best for me) a 30* shackle angle with the weight of the truck resting on the springs.

At full droop, (tires hanging), you should get about 5-6* forward angle on the shackle.

Use some large, heavy duty C clamps to position and hold your shackle flip brackets to the frame, which will allow you to fine tune the angle and get each shackle to match. It took about 4 tries to finally achieve the desired angle. And once you get angle set, make sure your clamps are holding tight, double check angles once more, and then burn them in or bolt them in.

I went from a 52 to a 64 inch leaf, so I just drilled new mounting holes when I found the spot I wanted.

Thanks for the info. I checked out yer 63" install, I think i've pretty much figured out what to do.