Ric Grassmick; Chandler AZ: I've really loved reading all your Chevelle- and El Camino–related articles over the past few decades, but I can't recall one about your '65 Malibu and the frontend setup for track use. I am retiring my '66 Malibu from drag racing and want to redo it with a bend toward open track and Pro Touring. As always, cost is an issue, so I can't afford an SC&C conversion or some kind of Corvette setup, which appears to be hot now. However, I can fabricate almost anything. For the rear, I plan on removing the ladder bars from the 9-inch and installing a three-link with coilovers and a Watts link. Since the car has a 12-point cage and has been back-halved, there are plenty of options for attachment points, and the tubs will allow any size tire (where a lot of money will have to be spent). I already have a Jeep 12:1 steering-box-conversion setup and a set of B-body spindles with 1LE brakes and a 15⁄16 T/A front sway bar that was on the car 25 years ago. I know nothing about front spring rates or control-arm relocation, like the Guldstrand mod on an early Camaro. Can you do this to a Chevelle? Everyone I've seen on the Pro Touring forums says this stuff is junk and a waste, but I can't afford $4,000 on an AST setup. Can you share any ideas?
Jeff Smith: This is a deep subject that, frankly, I'm not as conversant as some experts on the Pro Touring websites. But beyond expounding on the virtues of zero bumpsteer and minimal scrub radii, as you've discovered, it's easy to quickly become overwhelmed with opinion that is often presented as data. So let's back up a bit. It sounds like what you're asking is if you can come up with a basic, entry-level front suspension that will allow you to compete at Pro Touring events and to not be embarrassed by your car's performance. For many years, I ran my '65 Chevelle with a front suspension configuration that many people now consider to be borderline crude, but it worked very well. So let's first take a look at how you could reproduce that, and then we'll transition to the rear.
My original front suspension consisted of a 1-inch-taller B-car front spindle, Global West tubular upper control arms, stock lower control arms with Global Del-A-Lum bushings, Koni single-adjustable shocks, a 900-pound-per-inch front spring rate, complemented with a 11⁄8-inch front sway bar from a second-generation WS-6 Trans Am Firebird. Along with a fast-ratio steering box like from an '88 Monte Carlo SS, you would have what I would estimate at 75 percent of a full-blown Pro Touring front suspension. I'd place the camber at negative three fourths of a degree, with 5 to 6 degrees of positive caster, and 1⁄32-inch toe-in. There are people who will immediately throw rocks at this setup because they claim the B-car spindles produce horrendous bumpsteer. My response would be “show me.” Basically, they are correct that there is bumpsteer inherent in using the B-body spindles, but it is so negligent as to not be an issue. In 25 years of road racing my Chevelle (including running a top speed of 167 mph in the Pony Express Open Road race in Nevada and averaging just under 150 mph for 90 miles), I have never experienced anything that I could call bumpsteer—and nothing even remotely close to “rip the wheel out of your hand” bumpsteer issues that others want you to believe. I have heard opinions that claim “I can show you massive bump with that combination,” which is true, but only if you measure bumpsteer at the extreme ends of the suspension travel. Their contention is there is significant bumpsteer at full suspension deflection—in other words, when the upper control arm bumpstops contact the frame. In that situation, the tires are barely contacting the pavement, so bumpsteer doesn't matter because the driver has very little control of the vehicle anyway! The opposite situation (where the suspension is fully loaded) can also produce bumpsteer. But if your car has fully compressed the front springs to the point of hitting the fully compressed bumpstops, this means that your front spring rate is way too soft to allow the car to compress that much. So increase the spring rate so the front suspension will no longer hit the bumpstops, and any bumpsteer response will disappear. So what we really should be talking about is roughly 1 to 11⁄2 inches of suspension travel on either side of ride height because that's where the car will spend 90 percent of its time. This will probably elicit a bunch of responses from the experts, but the reality is that there's nothing wrong with running B-car spindles on a Chevelle. Is there a reason to change these spindles and improve the overall front suspension performance? Absolutely, and there are spindles out there to do that job. We're not talking about the ultimate front suspension here. We are talking about a front suspension that you can easily bolt on and go out and have fun with your car.
You also mentioned the Guldstrand upper control arm modification that was popular for the early Camaros. This was done to help compensate for the short Camaro (and Chevelle) spindle by relocating the upper control-arm mounting (pivot) point lower. You don't need to do that when using the Global West tubular upper arms with the taller spindles. One thing you might consider is improving the front suspension's anti-dive. In my experience, the stock Chevelle performs very poorly in this area. Even with 900-pound-per-inch front springs, the nose still takes a serious dive under hard braking. If you look at the front upper control-arm mounting points on a C4 Corvette from the side view, you'll notice that the front mounting point is significantly higher than the rear mounting point. Effectively, the upper control arm points up at the front. This is one way to create what is called anti-dive. If you have an understanding of rear suspensions and how 100 percent anti-squat works, then this is a similar situation except under braking. We don't want to achieve more than 100 percent anti-dive because then the front suspension will rise under hard braking, and there are many reasons why this isn't a good idea. But improving upon the stock Chevelle's bad habits is a good thing. The trick is to not overachieve. I would suggest calling Global West and talking with Doug Norrdin about this, if you are serious about moving in this direction. He has developed a new product that will help with this, but I had to promise not to talk about it in print because Doug says he's tired of educating his competition. The solution is incredibly elegant and is bolt-on simple.