Live axle doesn't quite light your fire? Buggy spring got you all banged up? As bulletproof and simple as they may be, there are a few times when Henry's old standby leaf-sprung wishbone/axle setup just won't cut the mustard.
Seeking better riding and handling alternatives, inventive builders have adapted everything from Corvair, Corvette, Jaguar, and Mustang II suspension systems to hot rod chassis. Over the past few years, we've seen serious improvements on the adaptation theme. Ultimately, independent suspension assemblies evolved from OEM donor parts to specialty parts engineered specifically for the application. One of the forerunners of this movement: Heidt's Hot Rod Shop.
Heidt's has built an entire company based on independent suspensions and they've recently incorporated some very desirable elements into a highly engineered rear suspension package. Their SUPERIDE IRS boasts the strength, durability, and parts availability of the Ford 9-inch third member, inboard disc brakes, and Corvette-style outer uprights with OEM bearing assemblies. The SUPERIDE uses all Heidt's castings, Wilwood discs, and Aldan coilovers. The result is a unique suspension system.
The same goes for their frontend. While Heidt's offers a Mustang II-based frontend for many applications, they also offer a SUPERIDE IFS system they've engineered from a clean sheet of paper. Heidt's designed their SUPERIDE IFS systems for applications where the Mustang II design simply doesn't fit. The differences include rear-mount rack-and-pinion rear steering (a must on pre-'35 cars) and a crossmember/control arm design that clears front fenders on these early cars. In other words, Heidt's SUPERIDE frontends, whether Mustang II-based, SUPERIDE, or SUPERIDE II, are a far cry from their IFS ancestors.
We visited Elgin, Illinois' Roadster Shop just as they happened to take on a Heidt's IFS/IRS job on a '32 Ford highboy frame. You may remember our Apr. '03 issue, in which we chronicled a '34 Chevy frame's construction at The Roadster Shop. While this frame differs in shape, The Roadster Shop's construction process doesn't deviate. They still use hot-rolled pickled and oiled steel; they still back-weld all frame faces (except the boxing plate); they still outfit their chassis with their signature tubular crossmembers.
Like we mentioned in the April article, The Roadster Shop's fabricated-frame method allows them great design latitude. They can stretch, kick, notch, pinch, or bob just by altering the templates' shapes. They form the '32 Ford's frame sweep reveal a little differently than standard. Instead of stamping the reveal, they shape each exterior frame panel by hand from two individual pieces. They then weld the two pieces together for an external face that mimics Ford's shape to a tee.
By back-welding the exterior frame panels they build material into the frame, which in turn allows them to radius the frame edges just as Ford did. In this case, a fabricated frame doesn't mean a tell-all fabricated-frame sharp edge. Nor does it mean the overly soft break formed by some aftermarket stamped frames.
Of course they still do this in their signature rotating frame fixtures that permit proper welds from all angles. Due to construction similarities and space constraints, we'll refer you to the Apr. '03 article for The Roadster Shop's general frame fabrication basics, but for now stick around and see what it takes for The Roadster Shop to whip up a Deuce frame with Heidt's components.
Like the Chevy frame we chronicled...
Like the Chevy frame we chronicled a few months back, Chad Glasshagel nibbled the frame panels from 10-gauge pickled and oiled steel. Note how the panel stops at the frame sweep. After trimming the piece he...
...loaded the panel into a...
...loaded the panel into a vise-like jig. The jig leaves the bottom inch or so open, whereupon Chad formed the lower edge with hammer blows.
He regularly checks progress...
He regularly checks progress with this gauge. This folded edge constitutes the lower radius for the fender reveal.
Then the frame panels go into...
Then the frame panels go into the frame jig. While this isn't the framerail we used, we showed this heavily kicked (4 inches) and stretched (3 inches) framerail to illustrate the flexibility that The Roadster Shop boasts.
Dream it up, and they can...
Dream it up, and they can do it to a frame (provided Bill O'Rourke agrees, that is).
After bending the two panels...
After bending the two panels for the reveal, Chad welds the two together. Once he welded the two, he ground everything smooth.
The latter photo shows the...
The latter photo shows the radius gauge Chad uses to check his progress.
After welding and grinding...
After welding and grinding the framerails smooth, the rails went into a rotational fixture. At this point, Doug Leetzow heliarc welded one of The Roadster Shop's proprietary crossmembers in place. The Roadster Shop's crossmembers provide ample exhaust clearance and incorporate a transmission crossmember pad.
With the crossmember in place,...
With the crossmember in place, Steve Vaughn located the Heidt's SUPERIDE crossmember and welded it in place.
With the crossmember in place,...
With the crossmember in place, Doug installed the chromed and polished stainless components, including coilovers and a rear-mount manual steering rack. (Note: We illustrated this assembly out of sequence for continuity's sake; The Roadster Shop leaves the chassis in jigs until the chassis assembly is complete.)
We thought we'd take time...
We thought we'd take time out to illustrate one of the SUPERIDE's features. Instead of slotted mounts for upper control arm cross bars and fixed control arms, the SUPERIDE uses tubular control arms with bushed and adjustable stainless rod ends. That one feature keeps control arms in their place permanently. Simply lengthen or shorten each arm's leg to adjust camber and caster.
Last but not least, Doug bolted...
Last but not least, Doug bolted the polished disc...
...brake setup to the suspension...
...brake setup to the suspension assembly.
For the rear suspension, Doug...
For the rear suspension, Doug welded in the brackets for the urethane-bushed crossmember. Then, after installing the crossmember, he hung the third member components, starting with the cast-aluminum center housing.
Doug then bolted a mock-up...
Doug then bolted a mock-up pumpkin and pinion plate in place. Two struts bridge the pinion plate to the forward crossmember to suppress the center housing's rotational torque. Doug trimmed the forward crossmember for perfect fit and...
...welded it in place.
Chad and Doug then bolted...
Chad and Doug then bolted the lower arms to the third member. Heidt's Gary Heidt emphasizes the beefy arms' ability to take tons of torque. Based on their heft, we tend to take his word.
Doug positioned the forward...
Doug positioned the forward struts' ends to the chassis center crossmember. These provide the rear hubs' lateral stability.
The caliper brackets not only...
The caliper brackets not only mount the calipers, but capture the stub axles as well. If installing parking brakes, these front brackets replace the small, front bearing plate. Heidt's uses Wilwood brake calipers for the application.
The halfshafts' inner flanges...
The halfshafts' inner flanges sandwich the rotor assemblies between the shafts and the stub axles. At this point Doug and Chad installed the coilovers to support the lower arms.
Chad bolted the uprights to...
Chad bolted the uprights to the lower arms. With the uprights finished, he installed the outer hub bearing assemblies to the uprights.
Chad and Doug then slipped...
Chad and Doug then slipped the splined halfshaft yokes into the bearing assemblies. They finished the axle assemblies by tightening the Heidt's-supplied yoke nuts to torque specification and locking them in place with the supplied cotter pins.
With everything installed,...
With everything installed, the polished Wilwood calipers finally mount to the rearend assembly with more Heidt's-supplied fasteners.
Doug then fabricated slick...
Doug then fabricated slick tubular engine mounts and welded the brackets in place with a dummy engine. The brackets use captive urethane bushings for mounts, so torn mounts are a thing of the past. At this point, the chassis only needs plumbing, paint, and wheels for full roller status. We can think of a car or two we'd like to shoehorn this under!