You see a lot of suspension stories in CLASSIC TRUCKS magazine, and for good reason: we're all a bunch of wusses! Well, maybe not wusses, but our standards of comfort have certainly been raised in the decades since our favorite fat-fendered pickups rolled down the assembly line. These days we want it all when we construct our classic cruisers--vintage looks, modern ride quality, and enough power to scare the heck out of the hapless person in the passenger seat.This story will help address two of those desires: comfort and power. We'll be following along as the crew at D&P Classic Chevy installs a No Limit Engineering Fatbar rear suspension on a '56 Chevy pickup (Don't fret Ford folks--installation will be nearly identical on most '48-66 Blue Oval applications.). The Fatbar is a setup that's designed to provide a better ride in the rear (more cush for your truck's tush, if you will), while also planting your pickup's power where it belongs--on the pavement.
Let's start with the comfort factor. Pickups start out with a ride quality disadvantage compared to cars because there's very little weight in the rear to help keep things stable. Couple that with the fact that many early trucks had stiff rear leaf springs to handle heavy loads and you can see why these old rigs were known for bouncing all over the road. There are a number of ways to improve the ride while retaining the leaf springs, but many rodders prefer to convert to four-link (or four-bar) style rear suspensions because they're more adjustable and, quite frankly, look trick. But it's not all about vanity--any drag racer will tell you that four-links transfer power more efficiently than leaf springs. And if done right, four-links can provide a smoother ride to boot.
According to No Limit's literature, the Fatbar system incorporates several unique design features to capitalize on that last asset. First are the bars themselves, which, at 30 inches, are longer than most to help achieve smoother weight transfer. They're also larger in diameter--hence the "Fatbar" moniker. The Panhard rod also measures in at 30 inches, and it mounts low and to the rear to provide a low roll center and less radial deflection. And finally, the Fatbar setup is designed to use coilover shocks with long (5-inch) strokes and soft (around 200 pounds) springs to really smooth out the ride.
Speaking of shocks, we used Ultra Ride coilovers (PN UR5855P) from QA1 Precision Products. These particular shocks provide soft compression and adjustable rebound rates, which allows the spring to handle most of the compression work and lets you dial in the rebound valving by choosing from 12 different settings on a knob at the base of the shock. The coilovers look trick, too, with a bright anodized aluminum body and a powdercoated "chrome-appearing" spring providing adequate eye candy without being overly flashy.
All in all, installation of the Fatbar setup was pretty straightforward, only taking D&P's Craig Peterson and Brandon Tabares a few hours' (that includes stalling for photos). That means a typical hobbyist could probably tackle the task in about a day, depending on his or her experience and the pickup's state of assembly (or disassembly). Adding to the ease of installation is the fact that all of the frame brackets are designed to bolt on, although the guys at D&P opted to weld them for optimum strength and a cleaner appearance. The only parts that actually require welding are the five brackets that attach to the axle housing itself. With that said, let's get on with the show.
Sources:
D&P Classic Chevy
18392 Enterprise Ln., #1, Dept. CT
Huntington Beach, CA 92648
(800) 647-1957
www.dpchevy.com
No Limit Engineering
455 South D St., Unit 4, Dept. CT
San Bernardino, CA 92401
(888) 297-6032
www.nolimit.net
QA1 Precision Products
21730 Hanover Ave., Dept. CT
Lakeville, MN 55044
(800) 721-7761
www.qa1.net
 Suspended and loving it! This...  Suspended and loving it! This '56 Chevy frame is in fat city thanks to its new Fatbar rear suspension from No Limit Engineering. |
 The Fatbar kit comes with...  The Fatbar kit comes with everything you'll need for installation, including a big bag of the necessary Grade 8 hardware (not shown here). The links and Panhard bar are already powdercoated, while most of the brackets are left raw so you can match them to your frame or axle housing. No Limit can also supply you with coilover shocks or air springs if you'd like. |
 We opted to order our own...  We opted to order our own coilovers from QA1 Precision Products. These not only look trick with their aluminum shock bodies and powdercoated coils, but can also be tailored to your needs with various coil spring rates and shock rebound valving that's adjustable with the turn of a knob. |
 The first step is a critical...  The first step is a critical one--getting the wheels where you want them. In this case all of the old suspension was already off the truck, so Craig set the bed in place temporarily, centered a tire in the fender opening, then marked the appropriate axle centerline on the frame. Make sure the centerlines are consistent from side to side by measuring to several fixed reference points on the frame. |
 |
 On '55-59 Chevys like this...  On '55-59 Chevys like this one, the old shock crossmember may have to be removed or relocated--a simple chore that typically involves just knocking out the stock rivets. Craig had already boxed this crossmember, so he sliced out his handiwork with a plasma cutter. |
 Assembling the links is easy,...  Assembling the links is easy, with polyurethane shells and steel sleeves in one end and forged adjuster bushings on the other. Screw the adjusters in until the four-link bars' eye-to-eye lengths are 30 1/4 inches, and the Panhard bar's is 30 1/2 inches. |
 A level, vertical line is...  A level, vertical line is marked 36 inches ahead of the axle centerline. This line will locate the four-bar frame brackets. |
 Craig then clamped the mounts...  Craig then clamped the mounts to the frame and loosely bolted the bars to them using the supplied hardware. |
 He did the same at the rear,...  He did the same at the rear, holding the rearend housing (a GM 10 bolt) in place with a floor jack at the approximate ride height. The axle housing should also be centered side-to-side at this point, and you'll want to make sure the four-bars are parallel to the side of the framerail from front to rear. |
 Before doing any welding you'll...  Before doing any welding you'll want to rotate the axle housing to achieve an appropriate pinion angle. The instructions provide the necessary information for doing this. |
 After all dimensions and measurements...  After all dimensions and measurements are checked and double-checked, the brackets can be tack-welded to the axle housing. It's best to hold off on final welding until all parts have been properly fit and measurements double-checked yet again. |
 Craig also tack-welded the...  Craig also tack-welded the frame mounts at this point, although these can also be bolted in place using the provided holes and hardware. |
 There's some assembly required...  There's some assembly required on the coilover shocks, but it's just a matter of putting the coil spring and a couple of collars on the shock body. Simple stuff. |
 With the four-bars secure,...  With the four-bars secure, Craig assembled the shocks and mounts and put them in place to see how they fit. The lower mounts should be fitted as far to the edge of the axle housing as possible. You may also want to trial fit your wheels and tires to make sure there are no clearance issues before final welding. |
 Once again the frame brackets...  Once again the frame brackets can be bolted in place, but Craig opted to weld them. |
 Next Craig assembled the Panhard...  Next Craig assembled the Panhard bar and brackets and put them in place for a trial fit. The frame mount is fitted to the bottom of the framerail 6 1/2- inches behind the axle centerline. The axle-housing mount should be
positioned so that the top of the bracket is parallel with the frame. |
 Again, Craig opted to weld...  Again, Craig opted to weld the frame bracket in place, though it can be bolted on. |
 The axle housing bracket was...  The axle housing bracket was then tack welded as well. |
 And here's the finished product...  And here's the finished product prior to final welding. Simple and attractive, the suspension should work as well as it looks. You'll notice that the frame rails have been boxed for extra strength in the area around the rear suspension. This is always a good idea. A C-notch above the axle housing is also a plus if you're planning on a low ride height. No Limit offers kits for doing both. |