Leaf-spring suspensions have been around forever, and there are tweaks you can do to make one spring work differently than another. You can taper the ends, use smaller leaves, use overloads, make bigger arches, relocate spring eyes, and so on. All of these things make leaf springs ride differently. But what about using longer leaves to absorb the vehicle's suspension force over a longer leverage arm? What is entailed in this sort of modification? Obviously, one spring hanger has to be moved. But what else? Remember that nothing is ever as easy as it sounds, and we definitely ran across that old clich again with this suspension build.
As far as custom suspensions go, this was a fairly simple project that you too could build at home with a welder. We used a '75 Blazer with a bolt-on 6-inch lift, a block-lifted rear, and some blown-out shocks as a test dummy and recipient of a new, much more supple suspension.
The plan was to make a slinky suspension that we could crawl and twist the K5 with, while still being able to jam down a stretch of dirt road or through the dunes at high speeds. We started the buildup with a set of 7-inch-longer Deaver front leaf packs, 14-inch-travel Bilstein 7100-series remote-reservoir shocks, Energy Suspension bumpstops, 11-pack rear leaves, and an Off-Road Design shackle flip. By the end of the project, we had also added new centerpins, a driveshaft, bronze shims, and Off-Road Design's 1-inch zero-rate add-a-leaf to the list. Follow along as we start the buildup and address any issues as they arise.
The front axle had been moved 1 1/2 inches forward with the new suspension setup. That, plus the fact that we had a lot more travel, required us to purchase a new driveshaft. We turned to the Driveshaft Superstore in Phoenix to get us out a new driveshaft that was the correct length and could deal with the more extreme angles this new CV 'shaft will see. They set us up with a 7-inch working travel yoke and 40-degree high-angle hybrid CV made from a combination of 1/2-ton and 3/4-ton parts.