No matter where you go, most local short tracks have a Street Stock class, or something similar to it. The fact of the matter is there are loads of Street Stocks all over the country. Although there are many different kinds of cars racing in these classes, and the suspension configurations vary greatly, the goal is the same. Everyone wants to win, and that starts with a solid setup.
John Chance is a former Super Late Model racer in Florida, who, after taking a few years away from the sport, jumped back into the Street Stock ranks. John picked up a super-clean late '70s Camaro, put his drivetrain combo in it, and went racing.
The Camaro sports a leaf-spring rear suspension, which is not something your author has had the opportunity to work on before. Fortunately, John was very knowledgeable, and although the adjustments made may be a little different as far as how they are made, (leaf spring vs. coil springs) the desired results are the same. John tells us more.
"Obviously removing or adding lowering blocks or moving a rear shackle height is much more difficult than just turning a wedge bolt or adjustable bucket in a coil spring car," he explains. "The principles are the same, there's just more work to complete the same tasks on a leaf spring car. Leaf spring cars generally require more pinion angle because of the ‘wrap' effect the leaf spring has under acceleration. The important thing to remember, I believe, is that just because you bolt everything into its place, that doesn't mean the rearend in a leaf spring car is square. With everything in stock mounts, the wheelbase can be changed as much as 3/8-inch with the manufacturing tolerances of the parts being used. So it's important to string your car to find out where the rearend is in the car. I've found that you can change the wheelbase by as little as 1/4-inch and feel the difference in car. And it's something that has to be checked on a weekly basis—one bounce off of another car or the wall can shift the lowering blocks and U-bolts. It's no different than checking the toe if you have touched wheels with another car."
Applying the basics to your car, combined with the right parts, and that can be the difference between running up front and mid/rear pack
On the scales, leaf spring cars are a little different than coil spring cars. John sheds some light on the differences. "Leaf spring cars usually don't need the amount of crossweight or wedge that a coil spring car requires—52 to 55 percent is a great starting point. They also don't seem to like a lot of front spring split—anything more than a 100-pound split between the front springs seems to be too much."
Sometimes "tricks" can be mistaken for attention to details. Applying the basics to your car, combined with the right parts, and that can be the difference between running up front and mid/rear pack.
"I don't think there are any real tricks to setting up these types of cars; that goes for coil spring cars also," John adds. "I think it's all about attention to detail. Make sure your car is bind-free, the upper and lower arms move freely. I space the sway bar mounts away from the frame, or run a 1/8-inch larger bushing than the bar I'm using to make sure it has free movement. I think a good quick steering box is also important in these cars—often the stock boxes are several turns lock to lock, which can make if difficult to run consistent lap times because your hands are all over the place in the car. I use a steering box off of an '86 IROC Camaro that is only 21/2 turns lock-to-lock, which means I never have to ‘shuffle' or reposition my hands on entry or exit. I also prefer manual brakes. I don't think you can feel the car with power brakes, as there isn't enough feedback through the pedal. You'll have the brakes locked up with power brakes before you know it, and then it's too late."
Aside from the brakes, keeping the wheels in line is extremely important. "Wheel spacers are a must with these cars because of the excessive amounts of camber you run on the right front," John tells us. "Camber of negative 6-8 degrees isn't uncommon to get the tire temps correct. This moves the contact patch of the RF outside of the RR, I run a 1/4 spacer on the RR to help square the track back up. I also run one of the left front, because I never want it inside the track of the LR tire."
Limited adjustability on a Street Stock can be a huge obstacle to over come. Sometimes it takes some out-of-the-box thinking. "The biggest obstacle with these classes are the limited adjustment you have to stay within the rules," John explains. "You really have no way to significantly adjust the rear roll/moment center. The Camaro front clip can be optimized to work pretty efficiently, but you can never get the rearend to catch up with the front to have a balanced car. After reading Bob's advanced chassis book, I came to the conclusion I was going to have to limit the front roll of the car. I tried it first with bigger sway bars, and that never made the car consistent for more than a few laps. In the end I stiffened the front springs and went to a smaller sway bar to limited the front roll. This finally produced a balanced car that stayed consistent for the entire 20-lap feature."
After reading Bob's advanced chassis book, I came to the conclusion I was going to have to limit the front roll of the car
John wanted to go over the setup in preparation for the 2013 racing season, and we took advantage of the opportunity to follow along and see how he does things. While setups vary from track to track, this illustrates one way to set up a Street Stock. What works here may not work for you and your car.
11 John’s car’s setup was very close when it rolled into our shop. This is partly because John has his hands on his car on a regular basis, and it shows with his record. In 10 races, John has won two races and finished in the top 3 four times. With this much success, we’re sure more feature wins are on the way!
