DRIVING A POWERFUL DRAG RACECAR – part 2 – The Burnout
by Bob Szabo
IHRA DRM - 2007 Issue #7
Continuing from the previous article, our racecar is all checked out, warmed up, and ready. We towed up to the staging lanes, and I am all strapped in for the race. Now we are given the go ahead to start up.
THE STARTUP: The crew chief squirts some fuel into the injector from a bottle in his hand. He takes one last look at the throttle to make sure it is closed. The removable starter motor is latched on to the front of the blower drive, and he flips a starter switch to spin the engine. I watch the oil pressure gage for pressure. It jumps up to about 50 psi from the starter motor speed. Then I flip the magneto kill switch ON, and the engine fires up in a loud roar! The oil pressure jumps to about 140 psi. I glance at the tachometer to confirm an idle speed of about 2,300 RPM. I am also looking around for anything unexpected such as smoke, fire, or a crew person reaction to shut it off. The crew chief keeps the engine running on primer until the mechanical fuel injection system is filled with fuel, pressurized, and feeding the engine. At that moment, the engine gets blubbery, and the experienced crew chief stops squirting primer fuel into the injector above the blower. The crew is jittery and excitable. Tow car doors get slammed. The primer bottle may get tossed. The starter motor cables get pulled off and may get tossed. The starter motor is disconnected and put in the tow vehicle. The Funnycar body is lifted. The support strut is removed, and the body is lowered down and latched. FOOTNOTE for evening races: the crew takes a careful look at the windshield to see if it is fogged. If so, they have a rag to wipe it down. Some teams have good luck keeping a cover over the windshield until it is lowered, then removing it at the last minute. That seems to keep the windshield from fogging up on a humid cool night.
DRIVER IN CONTROL: In this daylight race, now it is all mine. The engine is still roaring at about 2,300 RPM idle. All that time that the crew was close to the front of the car starting it, I was concerned about holding the car still. Now they are away from danger. The front is clear. I look towards the starting line to make sure I have an unobstructed pathway. I establish that in my mind before I move the racecar. It is important because something can go wrong and you may need an escape pathway as you pull forward. I blip the throttle to make sure everything sounds right. Even a slight blip jerks the car and leaves a sensation of pure power in a thrill seeking driver’s mind. I look out the windshield, around my blower and injector. They protrude out of the hood, blocking my forward view. My view is to either side and to the extent of the window forward pillars. My tunnel vision that began with putting on the full-faced helmet is completed. You just do not see much out of a Funnycar. Other than limited visibility, the remainder of the driver seat experience is an absolute thrill. At idle, the racecar body and frame jump around a bit. The body and engine do not move in perfect harmony. There is flex between the two. The first time I saw that, I wondered if the engine or body was secured. Subsequent checking confirmed it. Now I am used to it.
TIME TO MOVE: Before I move forward, I put the transmission in high gear in preparation for the burn out. I glance at the oil pressure gage. It has dropped to 120 psi as the oil gets warm. I look for the crew chief. We have a pattern. He always stays about 20 feet to the front and to the side of the racecar. He stays on the side opposite the center of the racetrack. I always watch the crew chief when I am behind the starting line. A Funnycar driver cannot see to either side or behind. I rely on him (or her on occasion) to be my eyes as I approach the burnout box. If I do not see the crew chief, I stay in place until I do. On more than one occasion, I sat there when a new crewperson forgot and ran to the starting line or walked behind the racecar after it was started. In those cases, they usually caught on and returned to be within my eyesight. My crew chief often holds his hand up as a signal not to move. Then from nowhere the other tow vehicle, a track official, or photographer crosses in front. None of those are good practice, but some of it happens from time to time. Then, with the approach clear, my crew chief motions me to pull forward.
BURNOUT BEGINS: I glance at the oil pressure. I ease out the clutch pedal a bit. Not all the way. I release the brake handle but keep my hand firmly on it with the other hand firmly on the steering wheel. I just let the clutch drag and the racecar moves slowly forward. Then as the front of the car goes over the water box, it dips slightly. I am also lining up the car for the burnout. I roll through the water box, and the rear tires dip and come out. This time I keep rolling forward about two car lengths from the water box. The crew chief drops his arm, and I release the clutch pedal and hit the accelerator to about 3/4-pedal for a moment, then back to about 1/4 pedal. The engine goes into a scream. The rear tires fry at close to 160 MPH even though the racecar is barely rolling forward. At this rotational speed, the tires grow in diameter, and the entire racecar lifts up giving you a kick in the seat of the pants. The rear of the racecar also jerks to the right from engine centrifugal force. All of this occurs in a fraction of a second. Driver experience is in response to all of these forces. The driver aims the racecar over the starting line with steering wheel movement, often unconscious of the actions and reactions. The racecar starts to lunge forward as the water under the rear tires thins out. I am turning the steering wheel a bit to the right to keep the front end in front of the rear end as the rear end tries to come around on the right side. There is a unique feel with every racecar to steer it on the center of the track during the burn out with that rear end trying to come around. With experience, I do not even think about it, but it was a learning task. Just a couple weeks ago, an experienced driver in a front engine dragster spun completely around by mistake on the burn out. The dragster did not hit the guardrail or leave the lane. It was a unique unintended event with no damage that reminded me of the risk. In the burn out, the racecar is gaining speed: 40 MPH, 50, 60, 70, … I am now seeing my own tire smoke.
I fly past the starting line and approach the 60 foot sensors, then past them. The racecar is a bit crooked, and oh darn it is time to lift. When I lift, I hit the brake handle at the same time. This practice grabs the rear tires from continuing to spin and keeps them from suddenly hooking up and jolting the racecar to one side or the other. Now I am continuing to apply the brakes, straighten the racecar out, and slowing down gradually to a halt. My heart is racing.
HAULT AFTER THE BURNOUT: The fuel injected engine lopes a few times as it approaches idle. I glance at the oil pressure gage to see if the engine has survived. The racecar is no longer moving. I down shift back to first gear. I engage reverse. Often the forward reverse cog will not engage. So I have to creep the car forward a small amount with clutch pedal drag to engage reverse. My adrenalin is way up there now as I back up to the starting line. To be continued …
As a courtesy from IHRA to our readers, previous Tech Stop articles can be viewed or downloaded from our website www.racecarbook.com click on Articles.
About the Author
Bob Szabo is an owner / driver of a blown alcohol drag racecar and one of the few technical racing book authors. His new book: “5,000 Horsepower on Methanol, with Nitro, Racing Gas, Nitrous, & Ethanol Technology” covers fuel injection, carburetors, normally aspirated, supercharged, and turbocharged setups. His current book, “Fuel Injection Racing Secrets” provides added tuning info for methanol. Both are becoming popular gifts for birthday and anniversaries such as that first 9 or 8 or 7 second ET! Check the DRM Yellow Pages for Szabo Publishing or look on the Internet at https://www.racecarbook.com or call (916) 419 6649.