Installing Offset Hangers & Shackles - Move It, Buddy

We swapped to polyurethane bushings, which are firmer and give a harder hit off the line than the stock rubber bushings. The poly bushings are an easy hand install. Just lube 'em and slide the two halves in place. A steel tube slides in the center for the bolt.

Since the front hanger bracket will be hard against the framerail, clearance must be made for the spring-eye nut on the backside. There are several ways to cut the clearance. We carved this slot using an aggressive carbide burr in a die grinder. The slotted shape (or a really big hole) is required to allow the bracket's mounting studs to slide into place.

Tucked away in the shop was a fresh A-Body, 8 3/4 rear assembly. We had rebuilt the unit, thinking it may come in handy one day. Inside are new 4.10:1 gears, a new Auburn Sure Grip, Moser hardened big bolt-pattern axles offset for B-Body brakes, and 11x2 1/2-inch drum brakes rebuilt with all new parts.

With the springs prepped and the new offset pieces installed, we bolted them in place. Notice how the front hanger is right against the rail. Visible is the front of the slot cut to clear the pivot nut.

The spring perches on the rear needed to be relocated to match the new spring position. The rear was supported securely with jackstands under the tubes, and adjusted until level with a screw jack at the pinion nose.

We moved the perches about 11/16 inch per side from the stock location. Measure carefully, keeping the perches at the correct angle and the same distance from each housing end. As a consideration for drag racing, we changed the pinion angle about two degrees further downward.

Next the angle of the original perches was measured so the replacements could be installed at the same relative angle to the pinion.

We did notice that the perches had a larger center hole than the pilot size at the leaf springs' center bolts. We whittled up these little tube adapters to make up the size difference and positively locate the rear to the springs. We tack-welded them in place over the center bolt.

With the springs dropped at the back, the prepped rear was rolled into position. The nicely painted rearend looked too good to go into this grubby old B'Cuda's chassis.

The 8 3/4's axle tubes measure 3 inches, while the 7 1/4's are a puny 2 1/2 inches. This necessitates changing the shock plates and U-bolts. We pulled a used set out of a box of miscellaneous rear-end brackets.

The 8 3/4 rear is 2.26 inches longer from the U-joint flange to the axle centerline, requiring a shorter driveshaft. Normally this would require a trip to the driveline shop, but luckily we had the old shaft from our 8 3/4-equipped Duster, which was just the correct length. It even had the 7260/7279 adapter U-joint we needed to adapt our small U-joint driveshaft to the new rear's large U-joint yoke.

Even with 10-inch slicks, we had plenty of room to go bigger on our Barracuda. The combination of our rear's wide B-Body brakes and the springs moved inboard will allow for a substantial increase in backspacing.