How do NHRA crew chiefs manage the unmanageable, unimaginable horsepower generated by nitro-burning Top Fuel dragsters and Funny Cars?

Brian Corradi, one of drag racing’s fastest-rising crew chiefs, is probably as qualified as anyone to answer that question. He left Funny Car racing following the 2008 season with the still-standing Funny Car speed record of 334.32 mph, set in 2007 by driver Mike Ashley. Less than halfway through his first season in Top Fuel, he already holds the fastest 1,000-foot speed ever in that class, 319.75 mph, set in the last race by driver Antron Brown.

“There’s no trick to it,” Corradi says. “They run fast when the motor’s happy – not running backwards [detonating] – and the air-fuel ratio is perfect, the clutch application’s just right, and you’re getting everything possible out of the back half of the track. I just applied what we were doing with the power, timing, and clutch in the last few hundred feet of the quarter-mile with the Funny Car to the last few hundred feet of this new 1,000-foot track in Top Fuel.”

Corradi has won or at least reached a final with every driver for whom he’s ever tuned: in order, Funny Car racers Dean Skuza, Frank Pedregon, Whit Bazemore, Mike Ashley, and Melanie Troxel, and, now, Brown. The Matco Tools team finished second at the 2009 Winternationals in Corradi’s Top Fuel debut and won the next time out in Phoenix. Since then, Brown has won again, set track records, and exchanged the Full Throttle points lead with perennial champ Tony Schumacher.

“Everything I knew about Funny Cars seems to be applying to Top Fuel,” Corradi said. “Funny Cars have a smaller ‘window,’ obviously, but we’re treating the dragster like it’s just as unforgiving, and I think that’s why it’s been so consistent. In reality, this is a Funny Car tuneup. With a dragster, you can just get away with more.”

Making power certainly isn’t a problem – anybody can do that. Controlling it is the problem. Having the exact same cc’s in every combustion chamber, consistent boost from the supercharger, and identical clutch wear because every disc and floater is perfectly flat – that’s what separates one team from another. The parts themselves haven’t changed much in years. Everyone runs supercharged, billet aluminum 500-cubic-inch engines with two magnetos, two fuel pumps, and a five-disc centrifugal clutch (a few diehards still run four-discs).

Setting the overall power level for a run is accomplished primarily through supercharger overdrive and compression.

“Some tracks – Denver, Bristol, Vegas – require a much more aggressive tuneup,” Corradi said. “You know it before you get there because you know the what the altitude is and you know that the conditions will be horrible. Topeka can be like that, too. The barometer’s the first thing you look at – that’s what determines static compression. A million things are always going through your mind, but I usually have a pretty good idea of what I want before I leave the pits.”

A simple nozzle change generally corrects hot or cold cylinders. In addition to the fuel introduced through the injector and supercharger, separate circuits feed the manifold and are plumbed directly into the intake ports, making individual cylinder tuning more precise. If more drastic measures are called for, crew chiefs can raise the compression in any hole by going to a taller piston, a slightly longer connecting rod, or a valve with thicker a margin.

Changing compression obviously isn’t a last-second, in-the-lanes fix. As fast as they are, crews can’t get the cylinder heads off quickly enough to swap in some thicker or thinner head gaskets. But even in the lanes, there’s still time to raise or lower the spoiler height on Funny Cars, bump the nitro percentage, or vary the blower overdrive, among other things.

Countless other adjustments are still available to tuners, minute but critical changes that can be made even after the previous pair has cleared the track and they’re on the pad, starter plugged in, awaiting the fire-up call. It’s a simple matter of popping the lid off the carbon-fiber computer box and turning knobs to reset clutch and fuel-flow timers.

“If you want to take the edge off or you see people ahead of you having trouble and you’re worried about smoking the tires or getting on the rev-limiter, you can take a little timing out of it,” Corradi said. “And you can always do something to the fuel system or the clutch right there on the spot. If there’s a particular point on the racetrack that you’re worried about, the ignition is the first thing you look at – that, and the clutch.”

Fortunately, those are exactly the things that can be monitored and adjusted right up to the last second. And, when everything’s going right and, more important, the conditions aren’t varying much, cars head for the lanes with only minor adjustments from the previous run.

“Why go making some big change?” Corradi asks. “That’s why your crew works so hard to make the blowers and all the other parts exactly the same. The crew is everything on a fuel car. Those guys make you or break you. The car will never be consistent from run to run – you’ll never know what’s really happening or if the changes you’re making are even having any effect – if the crew can’t have every single part like it was for the last run. I’ll run the same blower all day if it keeps measuring [to the thousandth of an inch between the rotors] the same. We did that in St. Louis and Phoenix [and won both]. Sometimes, you can run all weekend on one blower and sometimes you can’t make two runs in a row with the same one.”

After the run data and the all information logged from previous years has been taken into account and every component has been gone over, a single variable remains that can, in an instant, wipe out everything a crew chief and his team have done to prepare. It’s not the track conditions, which can be monitored, but the track prep itself, the last-minute spraying, scraping and grooming of the surface by NHRA officials.

“You know all your numbers, know your repeatability, know your tires, and know your clutch and fuel system are perfect, and you can even compensate for the weather because you’re tracking it,” Corradi said. “But you can’t do anything about how the track is prepared. You’ve got everything where you want it to be, but is the track going to be the same as it was last round or not?”

Trying to harness 7,000 horsepower, you never really know for sure.

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