hot rod suspension, street rod suspension,

Suspension Solutions – Proving There’s More Than One Way To Do Everything

It’s been said that there is more than one way to skin a cat, and despite never having cause to test that theory, we have found more than one way to deal with the front suspension of a hot rod as well. For the most part what we’re dealing with here are Ford-based front axles and independent suspension options and while some of what we’re showing are tried-and-true arrangements, others are a little more creative. The intent for showing them all is to provide a little food for thought.

hot rod suspension, street rod suspension, johnsons hot rod shop chassis, goodguys giveaway 1932 ford coupe

The ground scraping-stance of the chassis for the Goodguys Grand Prize Giveaway ’32 Ford Coupe is the result of a deeply dropped tube axle and a custom flat crossmember that raises the spring in the chassis. Built by Johnson’s Hot Rod Shop, this chassis also features JHRS machined wishbones and Ridetech shocks.

ford wishbone, hot rod suspension, street rod suspension

From the factory Ford front suspensions were simple but effective. The alignment of the pivot points at the center of the spring and the end of the wishbone allowed lots of travel with no binding.

In part thanks to stubbornness and also because it was relatively cheap, Henry Ford used the same basic front suspension design under his cars from 1908 to 1948. Simple and effective, it consisted of a solid beam axle, transverse spring, and a wishbone-shaped locating device that was anchored to the chassis in line with the spring’s attachment point. The design worked reasonably well in stock form, but hot rodders found that engine swaps and chassis modifications often required the wishbone to be split and the ends anchored to the frame rails. This necessary evil still located the front axle and provided the room necessary for modern engines and transmissions, but splitting the wishbone causes the suspension to bind in many circumstances. As examples, when the car leans in a corner, or one wheel encounters a bump, the individual radius rods move in different arcs—one moves closer to the frame and the other moves away. That means that the radius rods will try and twist the axle. Oddly enough that isn’t as big a problem as it would seem to be with an I-beam axle, as they will twist to a certain degree. Although some will debate this, the fact is tube axles won’t twist, which creates the bind described. As a result, I-beams tend to be better suited to split wishbones and hairpins while tube axles are better suited to four-bars. Of course, I-beams are compatible with any locating device.

hot rod suspension, street rod suspension, split wishbones speedway motors

Split wishbones obviously alter the basic geometry principles of Ford front ends, but often there is no other choice. The best option is to make them as long as possible with the ends close together if possible. This setup shows aftermarket wishbones from Speedway Motors.

Another interesting issue crops up when using an aftermarket axle with an original Ford wishbone, split or intact. Reproduction axles are either 2 or 2-1/4 inches wide at the perch boss. However, Ford wishbones (depending on the year) measure 2 or 2.300 inches (2-1/4 plus .030 inch). As a result, if a wide wishbone is used with a 2-1/4 inch axle there will be a gap. Rather than trying to overtighten the spring perch bolts (which doesn’t work), the solution is a spacer set from Pete & Jakes.

hot rod suspension, street rod suspension, spilt wishbone spacers

Splitting a Ford front wishbone, spreading the ends apart and attaching them to the frame rails is often necessary with an engine swap. However, using a reproduction axle with stock Ford wishbones, split or otherwise, can result in a gap between the two depending on the combination of parts. Shims are available to make up any difference.

Being the resourceful types they are, hot rodders have tried countless suspension variations over the years. Different means of locating the front axle, types and location of springs and shock absorbers, and different design theories have all been tried with varying degrees of success.

hot rod suspension, street rod suspension, torsion bar suspension, volks rod

Kent Fuller’s Volks Rod had a torsion bar concealed in the front crossmember, something he often did on dragster chassis. The attachment links to the axle also served as friction shocks.

hot rod suspension, street rod suspension, coil spring

Over the years a variety of coil spring applications have been tried. Most met with limited success due to the abbreviated length of the coils – not to mention they looked out of place.

hot rod suspension, street rod suspension, underslung leaf spring

Veteran hot rodder and journalist Neal East collaborated with the late Darrell Zipp to build the Rocky Mountain Low that featured an underslung front suspension. The frame rails were below the Willys axle with the spring above and the shocks are lever-action hydraulics.

hot rod suspension, street rod suspension, coilspring

Of course all bets on practicality were off when it came to show cars in the ’70s, as this mid-mounted single coil spring proves.

And thanks to the introduction of reproduction suspension parts, including new dropped axles, assembling a safe, traditional-style front suspension is easier than ever. But arguably the most impactful development for hot rods was the introduction of easy-to-install independent front suspension systems based on Pinto/Mustang II architecture. Best suited for fat-fendered vehicles due to their design and non-traditional appearance, these IFS kits had much to do with the growth in popularity of cars from that era and later because they worked well, were affordable and easy to install. Of course, it didn’t take long for high tech, custom IFS systems to become available for non-traditionally styled earlier cars.

hot rod suspension, street rod suspension, roadster shop chassis

This beautifully executed pushrod front suspension was designed and fabricated by the Roadster Shop for Jeff Breault’s ’34 Chevy roadster, which was built by Devlin Rod and Customs and won both America’s Most Beautiful Roadster and Goodguys Street Rod of the Year in 2022. Note the coil-overs are mounted horizontally below the Chevy’s frame rails.

hot rod suspension, street rod suspension, coilover IFS

Independent front suspensions come in a variety of configurations. This stylish Heidts Superide on Sonny Freeman’s ’32 Ford uses custom spindles, tubular control arms, and Ridetech coil-over shocks. Note the steering rack is mounted to the rear to make it compatible with most early cars.

hot rod suspension, street rod suspension, Mustang II IFS

Some of the most popular IFS swaps, particularly for fat fendered cars, are the Mustang II variants. This example from Fat Man Fabrications used tubular control arms and factory style coil springs. The steering rack mounts to the front of the crossmember, which works with fat fendered cars.

hot rod suspension, street rod suspension, Mustang II coilover shock

A popular upgrade to a Mustang II installation is the addition of coil-over shocks. Dialing in the ride quality is made easier by replaceable springs and ride height can altered by adjusting the preload on the coils.

hot rod suspension, street rod suspension

Air springs are often considered primarily for their ability to drop the vehicle on the ground when parked. However, when the proper air spring is used at the correct pressure they can be practical too, as they provide a smooth ride with the ability to adjust for varying vehicle loads.

When it comes to choosing front end components and arrangements, there are a wide variety to choose from. To paraphrase the saying concerning cats, there’s more than one way to suspend a hot rod, too.

hot rod suspension, street rod suspension, hairpin radius rods

Another option for locating the front axle are hairpin radius rods. Like split wishbones, they are best used with I-beam axles.

hot rod suspension, street rod suspension, coilover shock

Less frequently seen are coil-overs on solid front axles. However, by eliminating the stock spring and substituting a flat crossmember, the front of the car can be extremely low, even without a deeply dropped axle.

hot rod suspension, street rod suspension, quarter elliptic springs

Another interesting variation is the use of quarter elliptic springs, like these leather-wrapped versions on the old Bo Jones T modified from the ’70s. They’re used in conjunction with split wishbones and friction shocks.

hot rod suspension, street rod suspension, torsion bar suspension, moal coachbuilders

Moal Coachbuilders uses a different approach with torsion bars on its ’32 T-bar chassis, mounting them in a transverse fashion within a special crossmember.

hot rod suspension, street rod suspension

Created by Troy Ladd at Hollywood Hot Rods, this dual quarter elliptic arrangement is reminiscent of the arrangement found on early Miller Indy cars. Along with providing suspension, the springs locate the axle – note the remote control hydraulic/friction shock absorber. This setup is found on Pat Gauntt’s ’32 Ford that won the Al Slonaker Memorial Award and Goodguys Street Rod d’Elegance titles in 2023.

hot rod suspension, street rod suspension, friction shocks, radius rods

This sanitary arrangement on Gerry Kerna’s Model A sedan uses friction shocks that attach to drilled radius rods with original Ford-style links.

hot rod suspension, street rod suspension, kindig, cantilever suspension

Another clever take on a dropped beam axle front suspension is this cantilever coil-over setup designed by Greening Auto for the Shadow Rods ’27 Ford roadster built by Kindig-It Design for the late Ron Meis. This allows the axle, which is located by custom-machined wishbones, to hang out in front of the grille and frame ends.