In this installment of Project Unfair, we get down to one of the truly unfair aspects of our build, the dual-mode suspension system designed by Art Morrison Enterprises (AME). In case you missed it in one of the previous articles, the performance goal for the Project Unfair '69 Camaro is to be the fastest all-around Pro Touring car on the planet. All-around means a car that will handle with the best Pro Touring cars on the autocross and road course and cruise to the grocery store. That's the easy part. But to be "all-around fastest," we also want to be able to run 8.99 quarter-mile times and 200-plus mph in the standing mile-which has never happened in a g-machine.
To achieve our 8.99 quarter-mile times with a high-level handling g-machine suspension is difficult, if not impossible. The suspension geometry, the anti-squat, instant center, and preload of a good-handling suspension simply does not work well at the dragstrip. Sure, someone could put an outrageous amount of horsepower in a g-machine and make a Hail Mary white-knuckle pass through the traps simply overpowering the track. But we want to drag race consistently and as safely as possible. We also do not want to be in a position where we are forced to make so much crazy horsepower that we lose the streetability of the package.
So, in the planning and scheming phase of Project Unfair, the absolute most time was spent on figuring out a way to make a suspension system adjustable enough to have great handling and drag race great. One of the caveats early in the planning was that we don't mind making changes to transform the car from g-machine to drag racer, but did not want to totally dismantle and reassemble the car to do it.
There are multiple suspension designs available and one could argue for hours and hours (and they do) on which system is best. The reality is there are five suspension designs that can all work great for handling. We spent hours and hours researching all the best suspension systems available. We reviewed the anti-squat and preload capabilities of each system. We looked at adding some adjustability to currently available systems. Yes, we could add some adjustability and improve some of these systems, but no matter what we did, we found compromises in either handling or drag racing. We explored every possibility but ran into issues with each design.
Let's look at the different types of rear suspensions available and my feelings about their pros and cons for this custom application.
Leaf Springs: This was part of the original F-body suspension design. There are leaf springs made for fine handling, and there are leaf springs made for great dragstrip performance, but they are hugely different from one another. Performance handling leaf springs are multileaf design and are very firm and can handle very well. Drag race leaf springs are often a monoleaf design and are very soft and springy and do not handle well. Each spring designed to do one thing performs rather poorly at the other function.
Torque Arms: There are a few torque arm conversions for g-machines that handle very well. But the problem with a torque arm is that when set up for handling, it is not a good drag race setup (especially at our power level). Yes, there are plenty of fourth-gen Camaros that will drag the rear bumper, but you should try to turn a corner in one of those cars set up for the strip. And it is not a matter of simply changing adjustments to make it do one or the other.