It never ceases to amaze us just how many people put up with faults on their hot rods that they’d never accept on a daily driver. This is especially true of cars that have been updated with IFS or other modern components. Sure, if you’re running a beam front axle and split ’bones, for instance, there’s a certain degree of acceptance of ancient suspension geometry. On the other hand, it’s amazing how many cars are running around with a transplanted IFS that sits on the bumpstops, doesn’t afford a decent turning circle without the tires rubbing the fenders, or bad geometry. Many of these cars were built years ago, with owners or subsequent owners continually putting up with the shortcomings.
Here’s the all-too-common...
Here’s the all-too-common IFS problem: Control arms at an angle when they should ideally be parallel with the ground; ball joints and steering rack joints already partway through their working angles; shocks bottoming out, putting undue stress on the welds holding the top hat sections of the crossmember to the chassis ‘rails; and suspension hitting the bumpstops regularly.
Leaveil Degree found himself in just such a position with an extremely nice ’36 three-window he’d bought. Already fitted with a Mustang II based IFS crossmember and tubular lower control arms, to achieve the low ride height desired the builder had cut the coil springs so the coupe looked good. Trouble is, it didn’t ride good. Sure, it went down the road well enough, but the control arms were far from level, putting the ball joints at an angle before any suspension movement occurred, the shocks were bottoming out, and it hit the bumpstops with alarming regularity.
We’d been chatting with our buddy Kiwi Steve Davies at Kiwi Steve’s Hot Rod Shop about this problem recently, and he mentioned he rectifies roughly one rod every month with this problem. If that’s just amongst his customers, there must be hundreds of cars out there suffering the same issues, so we arranged to come by his shop the next time such a car came in. Degree kindly allowed us to photograph his ’36 during the transformation.
Same Answer, Different Angle
With the front wheels removed...
With the front wheels removed and the chassis safely supported on jackstands, the strip down could begin. Note this isn’t some pristine show car, but a real-world, regularly driven hot rod.
With the brake caliper unbolted...
With the brake caliper unbolted and supported on a jackstand (meaning the brakes would not have to be bled), Kiwi Steve removed the hub and rotor assembly from the stock Mustang II spindle.
A ball joint splitter was...
A ball joint splitter was used to separate the steering tie-rod ends, thus saving the rubber boot from the damage inflicted by a pickle fork-style splitter, and subsequently fit for reuse.
With a jack placed under the...
With a jack placed under the lower control arm, the upper and lower ball joint nuts were loosened, but the nuts were left in place. Without the jack in place, if either ball joint released, the coil spring could fly out and cause injury. Never underestimate the forces contained within a compressed coil spring!
With the lower arm safely...
With the lower arm safely supported, the splitter was again used to remove the lower ball joint.
The lower arm pivot bolts...
The lower arm pivot bolts were loosened to allow it to swing freely for spring removal, rather than work against the bushings. The same applies to the upper pivots.
Although Heidts 2-inch dropped...
Although Heidts 2-inch dropped spindles are planned, Kiwi Steve removed a single coil from the new springs to sneak up on the desired ride height.
With the cut coil removed...
With the cut coil removed from the stock spring (left), the difference between it and a new version is plain to see. These CPP springs are for a big-block Mustang II application, and are heavier duty. There are a number of variables that make it advisable to use a stiffer spring, which can be cut down to suit, depending on the IFS manufacturer, the relationship between the top hat and the lower control arm, and the weight of the body and running gear.
The coils were installed with...
The coils were installed with the new spindles and the ride height checked, which was still a little too high. Removed once again, another half coil was cut off, which gave the desired ride height. This is time consuming, but necessary to achieve the correct height. Cut too much off in one go and you’ll be buying another set of springs!
Before final installation,...
Before final installation, you can see the new compared to the old. The big-block springs ended up half a coil longer than the stockers, yet will offer more suspension movement as the new spindles offer a 2-inch height drop, meaning the lower arms will now be level.
With the brake caliper moved...
With the brake caliper moved for a clear view, the new spring was installed and the lower control arm jacked into place to apply a little pressure to the spring. Note the lower end of the spring is seated correctly against the stop on the control arm.
With the stock spindles (right)...
With the stock spindles (right) next to the new Heidts 2-inch dropped steel versions, it’s clear to see the difference. Moving the actual spindle (where the hub mounts) up the assembly means the ball joints are 2 inches lower.
Reassembly is literally a...
Reassembly is literally a case of reversing the disassembly process. With no wear in the ball joints, tie-rod ends, or rubber boots, everything was reused.
With the suspension assembled,...
With the suspension assembled, the upper and lower pivot bolt nuts were tightened (arrow).
After the caliper was re-mounted...
After the caliper was re-mounted and new cotter pins installed in the ball joint castle nuts, new shock absorbers were installed.
Here’s a useful tip: The threads...
Here’s a useful tip: The threads of the outer bolt attaching the ball joints to the upper arms (arrow) fouled against the top of the new spindles on full travel, but simply reversing it, putting the nut above the arm, solved the problem.
With everything tightened...
With everything tightened and the ’36 back on its wheels, the difference can clearly be seen. The lower control arm is now parallel with the ground, the ball joints are not at an angle any longer, and there’s more suspension travel before the bumpstops are reached. Now it’s off to the alignment shop.
The coupe sits exactly as...
The coupe sits exactly as it did before, but with less negative camber, and is much nicer to drive now. That’s a lot of improvement for little downtime. Mission accomplished!