Our '67 Firebird certainly looks dramatic, but its stock suspension was in need of refurbishing. You can see here that the severe body roll caused heavy understeer when pushed into a turn at moderate speed.
Modern technology has vastly improved the ride and handling characteristics of vintage Pontiacs, and the various high-dollar packages we see today often combine coil-over- and/or air-spring-type suspension systems with large aftermarket wheels and tires.
Those who have successfully installed these systems onto vintage Pontiacs enjoy their effects. They might consider vintage suspensions ancient technology and wonder why any hobbyist would attempt to improve upon it. There are, however, a large number of budget-minded hobbyists who much prefer expanding upon the existing design, while maintaining original appearance-and that describes us.
The Assessment
Our '67 Firebird convertible has been the subject of past HPP articles, and much of its suspension remains unmodified since its purchase in 2000. When compared to our Second- and Fourth-Gen Firebirds, our First-Gen's original 0.688-inch front sway bar and front coil springs, aftermarket front and rear shock absorbers, stock multi-leaf rear springs (to replace the mono leaf), and no rear sway bar leave much to be desired.
We never intended for this particular Firebird to be a corner carver, and instead performed a sheetmetal restoration with the hopes of creating a drop-top cruiser boasting predictable road manners. The result, however, was a beautifully-painted Firebird that dipped so severely over normal street imperfections that its near-stock-sized front tires rubbed the top of each inner fender well. Body roll was so severe that it caused erratic understeer when pushed moderately into normal turns, lending to its appetite for front tires.
There was noticeable improvement after installing urethane body bushings, a pair of modified sub-frame connectors, and 15x7-inch Rally II wheels with modern 235/60-sized rubber. It wasn't long after that we realized our Firebird's original suspension simply wasn't suitable for normal street duty. We began considering all available options, but had two major stipulations throughout the process-our choice had to maintain stock-type appearance, and it had to be at an affordable price.
Performance Suspension Technology in Montville, New Jersey, supplied us with a plethora of suspension pieces that were aimed at improving our Firebird's ride and handling qualities. In addition to the hardware, which carries a limited lifetime warranty against defects, PST's Polygraphite bushings are graphite-impregnated and are claimed to be less prone to squeak when cold.
Decisions, Decisions
Our past experience with urethane bushings has shown positive long-term handling improvements when compared to rubber, without compromising stock appearance. We also felt that a larger front sway bar, and the addition of a rear bar, would be an easy way to positively change our Firebird's attitude. We decided to follow our instincts, and started visiting various Web-based forums, searching for present offerings.
One of the companies frequently mentioned was Performance Suspension Technology in Montville, New Jersey, so we contacted its technical department seeking suggestions. We explained our objective, and were told that a 1.125-inch front- and 0.875-inch rear sway bar kit should provide substantial improvement, and that combining these pieces with a host of other components would give our Firebird a significant attitude adjustment.
Following the company's recommendations, we ordered its suggested G-max front and rear sway bar kits with Polygraphite bushings, a Polygraphite control arm bushing set, KYB Gas-A-Just performance shock absorbers with Polygraphite bushings, Ground Zero front coil springs, and a Polygraphite rear traction arm ("radius rod" in Pontiac speak) bushing set. The entire purchase set us back around $825, which included free shipping to the lower 48 states, and everything arrived on our doorstep within a few days.
We started by removing the front sway bar, which was a simple task. After removing its end links and mounting bracket bolts, it easily slid out through the wheel well. | 
While a number of methods for removing front coil springs exist, we used a high-quality hydraulic jack and a series of large jackstands to remove our worn originals. We raised the Firebird's nose several inches off the ground and supported its body with jackstands. We then positioned the jack under the lower control arm's ball joint, allowing it to smoothly roll as we slowly released spring tension, after the upper ball joint was separated from the spindle. We cannot stress enough: Use extreme caution when dealing with front coil springs! The energy stored within can cause serious bodily injury, or even death! | 
We proceeded to remove the upper and lower control arms, but first treated the nuts and bolts of both to heavy doses of penetrating lubricant. (Remember the alignment shims that are sandwiched between the upper control arm and the front subframe. Reinserting them into their original position during reassembly should provide enough wheel alignment to get to a nearby repair garage for professional service.) |
The control arm's original bushings were in poor condition, so we opted for a set of PST's Polygraphite ones. Removing the originals and installing the replacements is accomplished using a large press, so we had Brian Carson at Universal Steering in Omaha, Nebraska, perform the task. | 
PST supplied us with a pair of its Ground Zero front coil springs. After asking us a series of detailed questions that included the option of retaining stock ride height, we received a pair of custom-made units specific to our application. When compared to the stock (320-lb rate) spring on the right, the Ground Zero (365-lb rate) replacement appears taller, suggesting that our originals may be worn. | 
Using a high-quality spring compressor to compress the springs on the bench, we then used a steel pallet strap to preload half the spring, making installation much easier. We remembered to correctly index the spring, so it properly fits the lower control arm pocket. |