The dirt street stock may be considered an entry level class at many tracks. However taming a street stock set up takes more than entry-level knowledge. Many sanctioning bodies and tracks do not allow any modifications to the suspensions of the car. Chassis builders have come up with ways to get around some of these restrictions, but drivers are left with few choices when it comes to race night. Feature winners and track champions have figured out the tricks-keep reading if you want to learn some of them!
We will focus on the typical General Motors metric chassis as they are the most common. If you are racing a leaf spring car your setups may vary. Our street stock is fitted with racing tires but does not benefit from screw jacks. Those who follow the street stocks in the WISSOTA Amsoil Racing Series (one of the Nation’s largest sanctioning bodies with over 400 licensed drivers) are familiar with these rules. You should consult your chassis builder on your initial scaling numbers as each chassis is different. One of my previous chassis builders suggested scaling the car with 55% for cross, left and rear weight! Unless you normally take your scales to the track, you will more than likely have to make other types of adjustments.
When you get to the track one of your first priorities should be to get a look at the track condition. I prefer to get a look before the water truck takes its last few laps. This will give you a better idea of what the track will be like after a few laps. The muck left on top by the water truck will probably get blown off within a few heat races. It is important to check the track out each night. Many tracks utilize volunteers and the track preparation may be inconsistent. Maybe the weather was poor during the week or maybe the track prep crew had a busy week at their personal jobs and couldn’t get out to work the track.
Lee Christjohn of Antigo, WI knows what it takes to win street stock races. Christjohn has been racing street stocks for 13 years and has amassed 74 feature wins and 4 track championships. Christjohn likes to get to the track early and get his car set up so he can watch the races. Heck, if you are paying 20 bucks to get into the pits you might as well enjoy the show! There is a little more to watching the races than checking out a buddy. Watching others could give you a clue as to what kind of changes the track is going through and what lines the fast cars are using. It is also important to pay attention to your tracks preparation between races. Do they water every three races or just before the first race of the night? These could all substantially change the way you set your car up for your race.
Typically you will run more stagger during your heat race. If your track likes the early races to be wet you may find yourself running around 3” of stagger. If you only have one size of tire available you can try “ballooning” your tire to increase its size. Ballooning is accomplished by filling the tire with an excessive amount of air and letting it sit in the hot sun for a while. You will want to consult with your tire supplier as to what a safe amount of air will be for your tire to avoid serious injury. Hopefully you have different tire sizes available and won’t have to go through the extra effort. To help get the car to turn into the corner you will want to create less stagger in the front end and less cross weight overall. This can be done by simply increasing the left front tire pressure. If you have the capability of moving some lead around, get it over to the right side. Depending on how wet the track is you may want to move your rear tires to the right as well. You can accomplish this by using a 2” offset rim on the right side and a 4” offset on the left side. If you don’t have different offset rims wheel spacers are an option. If you have the opportunity to run a softer compound tire, a wet track is the time to use it. I like to use them on both rear tires. The shorter race will probably not burn it them off (if it is wet enough). I also use the softer compound on the left front tire at all times.
Hopefully your setup has landed you in the feature and not on the flatbed! If you have an intermission use it to get a closer look at the track instead of filling up on cheese curds. Pay attention to if the water truck is back out or if the grader is out. Check out the corners and see if there is any tacky real estate left. The straights may even surprise you and you’ll find a better line a lane or so off the wall where few others have been. Find out where you start your feature and who is in front of you. This may help you develop a game plan as to where you want to run on the track and how you want to set the car up.
By feature time most tracks will have become dry slick. Those of you that have dry slick tracks from the minute the first car takes the track can forget the last couple of paragraphs! The later you run in the program the more of these changes you may want to make. When it gets a little dry, Christjohn likes to take some of the stagger out of the rear end. Some guys even run a larger left rear than right rear (reverse stagger). Take the rear wheels and get them moved to the left side of the car. You may want to reverse the offsets and use a 4” on the right side and a 2” on the left side. If you need to get the car a little tighter, move the weight back to the left side. Christjohn also likes to add some shims (or spacers) to the left rear spring to increase the cross weight. This can also be accomplished by dropping the tire pressure on the left front a couple of pounds.
Hopefully you have invested in a tire pyrometer by now. They are invaluable and inexpensive. Even after many years of racing I still take tire temperatures after every race to ensure peak tire performance. Since heat races are a little shorter, your tires will probably not build as much temperature and pressure. Christjohn agrees that you will usually start with higher temperatures in the heat races than features. You may also want to run more pressure on higher banked tracks, especially on the right rear as the load is dramatically increased by the quicker corner speeds.
Remember not to get fixed on one setup for your home track. Weather, car count, and what order in the show you race could change weekly. Differences in each will affect the track and how your car should be setup. You may need to try some of the changes listed above or all of them, but be flexible! Even a one pound difference in tire pressure in the right rear could mean the difference between a feature win and a middle pack run.