Drag racing tips for your street car

Many amateur drag racers already know the tricks, tips and techniques to help their car go faster and more quickly at the dragstrip. However, there could be a few you're not aware of. Additionally, there is one potential major misconception and a technique for automatic and perhaps manual transmission cars that could be key as well. Listed are some obvious old-school and some not so obvious tips due to rampant electronics in modern cars.

Weight reduction - easily established by racing with a low tank of fuel. Modern fuel injected cars won't run lean with less fuel - don't worry. Remove the spare tire, etc. Removing rear seats (if equipped) is not uncommon. However, a totally stripped interior, if a daily driver or even weekend car, just really looks cheap and junky unless the interior is purpose built and finished for racing. Edit: Extra weight in the rear may allow for a lower 60-foot time and hence lower ET while making only a minor difference in trap speed. Experimentation is the key. 

Run cooler - icing the intake manifold. Cold air is denser air which translates to more horsepower. A hot engine will heat incoming air. There isn't much that can be done with the ambient air temperature, but running extra hot doesn't help. Without going deeply into modifications, a lower temperature thermostat is used for this reason. Push your car if feasible instead of the stop-n-go in the staging lanes. There are handheld tuning tools and even fusebox modifications that allow the cooling fans to start and run at lower than factory-set temperatures. Being the only guy pushing your nearly 2-ton car gets old real fast.

Something you may not know regarding running cooler. Some cars actually make more horsepower due to fuel programming when coolant temperatures are below 180 degrees vs. the normal operating temperatures of 200 degrees or higher. The balance of engine temperature, fuel economy and emissions is altered when seeking maximum power at wide open throttle.

Tires - lower tire pressure may very well be worse for two reasons. Losing traction from lack of grip means sitting and spinning while your opponent is accelerating. Also, if there is an increase in the rolling resistance of the tires, that is a parasitic drag. Every little bit counts when counting in tenths of a second or miles per hour.

When equipped with high performance low-profile tires which have stiff sidewalls, a common misconception is that if you lower the tire pressure significantly, you'll have more traction. This is because racing slicks use lower tire pressure to soften the sidewalls and increase the size of the contact patch. If the modern low-profile tires have structurally stiff sidewalls, less air will mean less contact patch in the center of the tire while the sidewalls maintain their stiffness. What is very important here is knowing how your tires respond to air pressure. Unless there is an established technique that is getting 60ft times below 2.0 seconds, try starting with pressure in the high 30s and work your way down. You may find a range that your car performs the best is far higher than those that are running 22psi in their low-profile 35 or 45 series high performance tires.

One last point regarding tires. The smoky burnouts look and sound fun, but do it for too long and a street tire can become slippery rather than sticky. A general rule used for non-drag radial street tires is do it just long enough to see smoke, then stop.

Fold your mirrors inward. Minor I know, it sounds silly, but trapping at 109.9mph vs. 110 can be frustrating. The competitors at the Bonneville Salt Flats who use duct tape to seal body gaps wouldn't laugh. Do you think that's allowed at the Texas Mile?

If equipped with adaptive shock absorbers, the "comfort" mode may allow for more weight transfer to the rear, facilitating better traction and a better launch. Conversely, "comfort" mode may also trigger a slower shift from the transmission with more slippage and even at a lower rpm. Who the heck drag races a car with a "comfort mode" anyway? Well, Mercedes Benz E55 owners with smaller-than-stock supercharger pulleys have been known to run 10-second quarter mile times. Crazy but it really pays to know how the various electronics influence the behavior of the vehicle.

Use a toilet brush to scrape debris off the tires. Buy a new one at the grocery store (please) and before you get in the staging lanes, a quick scrub will remove some of the larger debris. Does it work? Well I'd say it doesn't hurt. Pebbles in the tread can cause voids in the contact patch.

Related to the toilet brush, VHT track bite traction compound helps immensely for traction off the line. Spray after taking off the debris and preferably by crew member after doing a brief burnout on your street tires. Granted, if track prep is fresh, this probably isn't necessary. At some tracks, it's essential for street tire cars. I wouldn't be surprised if some of the street tire equipped cars that run fantastic times do this during track rental days.

Adaptive transmissions and electronics can be the most confusing and impactful of the various necessary steps to run the best times. It's important understand your car and how it reacts. Read up on the forums from other owners for their techniques. Others may do certain routines not even realizing why they seem to work. I'll list examples of how some cars respond to various inputs.

A slow diagnostic transmission shift may occur after start-up. Not noticed during daily driving, but at full-throttle, it could be painfully apparent, hurting trap speeds. One resolution I'm aware of is to drive over 20mph before lining up at the lights so the initial 2nd to 3rd gear shift is done. Even a single or dual clutch automated manual might do this. At some dragstrips like Infineon Raceway at Sears Point, the staging lanes are so close to the "christmas tree" this occurs.

Manually shifting the automatic transmission, while not as consistent, may make for firmer shifts. On the other hand, another car may shift better if simply left in "Drive". Further complicating things nowadays some mechanical tachometers actually can't keep up with the engine speed which means easily "banging" off the rev limiter when manually shifting while trying to judge the optimum shift rpm. Hitting the rev limiter means blowing your run and maybe losing. Lexus actually has a digitally simulated tachometer for this very reason in the new LF-A. Remember, this can apply to automatics, dual clutch and single clutch automated manual transmissions.

Lastly, when you sometimes pull the fuse to the transmission, it resets the "adaptives". What this means is some types transmissions will "learn" how you were driving previously and mimic that. For example, if you're idling at the stoplight waiting to enter the track, slowly driving to tech inspection and finally in the pits, your transmission could possibly store this and repeat this in the form of sluggish yet smooth shifts. Pulling the fuse will reset it to the default setting and the wide-open throttle will signal faster and firmer shifts. This can really make for a literal checklist.

Modern cars with all the electronics that make our lives easier and safer also are a pain in the butt to extract the maximum performance they are capable of. Keep in mind the basics - keep it cool, learn how your tires react to air pressure changes and finally learn how the electronic nannies hurt or help your car.
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