5.0 Mustang & Super FordsHow To Engine
Drag Racing's Basic Strip Strategy - Five By Five
Five Basic Tips And Hardware To Shorten A Quarter-Mile
Drag racing is a precise game where the difference between victory and an early trip to the trailer can often be measured in fractions of inches and thousandths of seconds. While any type of race can be won by a close margin, in how many other forms of motorsport can your car successfully contest a whole weekend's race program by participating in less than a single minute of actual timed competition?
In this intensely time-compressed pressure cooker, we have to make those brief seconds count. With this as a handy excuse, most of us will happily rush out and invest in the latest and greatest go-fast add-ons for the car-even if only to make it a few hundredths quicker. And we at this magazine certainly fill a lot of pages talking about all this e.t.-shortening hardware. But some of the stuff that can improve your dragstrip timeslips doesn't bolt to the car at all, and that's what we're here to look at this time around with the help and advice of modular shoe and chief gearhead of Paul's High Performance, Paul Svinicki.
At first glance, the concept of a drag race is deceptively simple: beat the other guy to a finish line that is only one, straight, quarter of a mile away. Simple as the concept may be, the execution is anything but, and as with any form of racing, it rewards a thinking-man's approach. Naturally, power and traction will play major roles in achieving victory, but driving technique and consistency are at least as important, as is the mental game. Some of the steps to more frequent success can be taken before you even reach the starting line.
No matter whether your contest is a heads-up or bracket class, one of the primary keys to success is consistency-or repeatability-in both car and driver. If your back-to-back e.t.'s are all over the map, the only person you're likely to beat is yourself.
We sat down with Paul Svinicki for some basic strip strategy and a quick look at some of the products he uses to help his own consistency. (By the way, Paul doesn't sell any of the following products but says they're available from Summit Racing and other vendors.)
1. Power Speed Calculator
So you have a $15,000 stroker under your carbon-fiber cowl hood, with a chassis and slicks that are second to none-yet your buddy can still whip your butt with his stock 5.0 winter beater on snow tires. Does your engine builder suck, or is your friend just a real stud behind the wheel? The Moroso Power Speed Calculator ($10) is a slide rule-type device that will give an accurate indication of what kind of elapsed time and miles per hour your combo should be capable of, assuming proper traction and technique. All you need do is line up your ride's weight (including driver) against its flywheel horsepower and read off its e.t. and trap speed potential. Why is this important? It gives a performance target to aim for with any given level of power, and it just might be an indicator that, rather than spending more money on horsepower to go quicker, you might instead spend more time practicing and honing your technique.
The Moroso calculator can also work in reverse as the world's cheapest engine dyno. If your car is consistently running up to its full potential, just slide to its e.t. on the scale and read off its flywheel horsepower opposite driver-included weight. Who knows? That mill you assume is cranking out 500 ponies may only be good for 350-or vice versa. Also capable of various other quick automotive calculations, for less than 10 bucks, this is something that deserves a place in your track toolbox.
2. Weather Stations
Unless you have more pull than we do, there's nothing you can do to control the weather, but your race-weekend strategy can surely benefit from a basic understanding of what effect temperature, relative humidity, and barometric pressure will have on your car's performance. "There can be two- to three-tenths in the weather, especially on naturally aspirated cars," Paul says, referring to the fact that as heat or humidity rise, or as the barometer drops, engine output takes a hit. Considered together, these three environmental factors combine to calculate what's known as density altitude, and the higher the density altitude, the less air molecules that are available for combustion. Blown or turbo'd applications are less affected since these compress air into the hungry cylinders regardless of its density.
The value of having a portable weather station with you at the track is that it lets you know what to expect of your car's performance on any given day. As Paul explains, "All of a sudden you're going two miles an hour faster, but you need to know if it's because of better weather this week, or is it that whiz-bang new chip or part you just installed?"
In knowledgeable hands, the weather station is also a valuable tuning tool, especially on carbureted applications, since the density of air molecules directly affects the amount of fuel needed to maintain an optimal air/fuel ratio.
We can't leave the topic of weather without also suggesting a wind gauge, since it's nice to know in advance which way the wind may be pushing you down at the traps. And after a run, you can hardly judge its success without knowing the direction and velocity of the mass of air the car was running in at the time. Some cars are more aerodynamic than others, but all will be affected by the wind. Sticking a wet finger in the air just doesn't cut it. Which leads us to the next suggestion-remember to log all these conditions so you can review and analyze the car's performance when the weekend is over.
Since consistency is so important, Paul highly recommends you make full use of a logbook for each test, qualifying, and race outing. The more detail you put in it, the more you'll get out of it. Trying a different tire diameter or pressure? Log it. Launching or shifting at a different rpm? Log it. Take all the data from your timeslips and log it. Then analyze it. Racers love to experiment, and a logbook is the perfect place to track the success or failure of that experimentation, while simultaneously keeping track of such uncontrollable variables as weather and track altitude. With everything logged, as the season progresses you can look back and get a clear picture of whether you and your car are likewise progressing. This is all part of the mental game that differentiates good drag racers from recreational wannabes.
4. The Timeslip Is Your Friend
You keep your timeslips, right? You should-at least long enough to log all the data they contain. Unwise racers just glance at this valuable slip of paper for no more than their e.t. and trap speed, which is kind of like buying Playboy and just reading the articles-they're missing some of the best stuff. Think of the timeslip as a free data-logging system that can reveal how both you and the car are performing at various points on the track.
Let's start with reaction time, which is a measurement of how long it takes your front wheels to completely clear the staging beam after the Tree's green light illuminates. "Reaction time," Paul says, "is not only you, but did the car react?" In other words, it times not only your launch reflexes, but the car's as well. If you get reaction times while driving a buddy's similar car that are consistently better than in your own, this would indicate your car is not reacting as well at launch. Common gremlins might be shock/strut combos, tire pressures, torque converter, gear ratio, or clutch slippage. Paul suggests having someone videotape your launches, which often reveals a problem, such as one wheel spinning because of a weak diff or chassis-setup issue.
Next on the slip comes the 60-foot time, which Paul insists is one of the most important indicators of a run's quality. "It starts there and ends there," he says. "If you go from a 1.5- to a 1.6-second 60-foot time, the e.t. difference is going to be even greater than that tenth at the end, 'cause you're multi-plying all that time over and over."
And 60-foot is totally unrelated to reaction time. Remember that though the race starts when the Tree goes green, the e.t. clock doesn't-it starts only when your front tires clear the staging beam. This means the 60-foot clock starts at the point where the reaction timer ends. And where reaction time represents a combination of human and mechanical reflexes, the 60-foot time is the first pure indicator of how the car is coming out of the hole. By the way, Paul believes there's little or no hope of consistent 60-foot times using a stock Traction-Lok diff. He suggests that when swapping to a more aggressive differential, you opt for a 31-spline version and upgrade your axles at the same time. He also considers a line lock essential for consistency.
Moving along to the 330-foot, eighth-mile, and 1,000-foot times, these can be an indicator of how effectively you or the car are shifting. Experiment a bit with shift rpm during test and tune, and examine these times to see how the car reacts. Miss an ideal shift point by, say, 500 rpm, and it will show up in these intermediate times.
The point here is that quarter-mile elapsed time and trap speed are only part of the story a timeslip tells you. Use it for all it's worth.
5. The Burnout
Finally, we can hardly talk drag racing without paying some attention to the burnout. Of course, the term "burnout" elicits images of John Force's half-track crowd chokers, but he doesn't have to buy his tires, does he? In truth, the ferocity of the required burnout depends on whether you run street tires, drag radials, or slicks. Recommended air pressures will also vary greatly between them.
Since they've become so popular, let's start with drag radials. Paul uses the Nitto Extreme Drag, running somewhere between 14 and 18 psi on his Mustang (a heavier vehicle, such as the Lightning, needs more pressure). When it comes to how much burn in the burnout, Paul says, "With a drag radial, you want to heat it until it's absolutely blistering-a good, long burnout."
On the opposite end of the smoke scale, Paul suggests pure street radials essentially need "no burnout-just whip the stones off them." Bypass the water box and dry-spin them a couple revolutions to get down to clean rubber. Paul believes that anything beyond this just brings out a street tire's oils and makes it greasy.
Slicks fall somewhere in between, except in air pressures where Paul favors 8-14 psi, depending on tire manufacturer, size, and vehicle weight. He recommends breaking in a brand-new pair of slicks with one good, long burnout, but after that a slick needs a much briefer burnout than does a drag radial. "Usually, just till the smoke starts to pour off them," he says. "A lot of guys way overburn their slicks-they just need to be cleaned off and warmed up."
And there you have it-just a few of the gadgets and strategies for quarter-mile competition. As with any form of combat, it must be studied to be mastered.