Tech Q&A: Jimmy Elledge

March 5, 2001
6:35 PM EST (2335 GMT)

ASHEVILLE, N.C. -- Jimmy Elledge joined Andy Petree Racing in 1999, its first full year of operation. Elledge has grown up around racing and his father, Terry, is a highly respected Winston Cup Series engine builder.

Elledge's driver Bobby Hamilton (left) and Petree teammate Joe Nemechek.

His career includes experience as a driver in the NASCAR Winston Racing Series, and this experience has helped Elledge become a better crew chief; in addition to his mechanical and technical knowledge, he has the ability to relate to what his driver is saying about the race car.

A crew member for Mark Martin's No. 6 Ford in 1998, Elledge previously worked at Richard Childress Racing for six years, performing various duties for the No. 3 Chevrolet team. He and Andy Petree worked together during that time, when Petree and driver Dale Earnhardt combined to win a pair of championships.

Elledge has been a crew chief in the NASCAR Busch Series as well.

QUESTION: What kind of differential in the rear end of stock cars do NASCAR teams use? How many races is one good for, and what do you do with old differentials? -- Chuck Deitz, Orange, Calif.

ELLEDGE: We use a Detroit Locker and we run a 9-inch Ford rear end. We use a nodular iron case for the gears to be built in and a standard Detroit Locker. We'll change the springs in them and maybe de-burr and polish all the internal parts on the ratchet, but that's it.

QUESTION: When fabricating a stock car frame and chassis, what do your body and frame technicians use to pull square and measure? What are some of the other tools they commonly use? How are the NASCAR garage body and frame technicians paid? -- M. Spalinger, Molalla, Ore.

ELLEDGE: Our body and frame technicians build a chassis in three different sections -- the roll cage, the front clip and the rear clip -- and they're each built on jigs. All the centerline data is determined from the jigs, plus there are reference marks we put on the front and rear clips after we build them. Then we have a main jig with one big plate where we put the frame rail section in and everything is already squared up on the plate.

There is one scribe line right down the middle of that plate. We take the front section and we've got a fixture that it bolts into. The front section locates by some dowel pins that go into the two-inch thick ground plate. We line the reference marks up from the build jig to the finish fixture.

Basically, that centerline that is scribed in the plate and we use just common old string to pull centerlines from. Other tools we use to measure with when building the chassis include a Faro Arm that is a digital computer layout tool and we actually use it to reference cars once they're built to make sure they're all the same.

The rest of what we use is just common old stuff -- tape measures, some precision squares, but mainly most of it is all fixtured so you don't have to do a whole lot except put the pieces of the puzzle together.

The technicians are paid by salary, from $30,000 for entry-level skills on up to $70,000-80,000 for an experienced body person.

QUESTION: In the NASCAR Winston Cup Series, all the teams run carburetion and I was wondering why they don't run fuel injection? What modifications are made to race carburetors to meet the needs of NASCAR racing? -- Jeff Weiner, Phoenix

ELLEDGE: We don't use fuel injection because it's not legal. You've got to have fuel management systems if you're going to do electronic fuel injection. NASCAR tries to keep onboard computer systems and electronics off of these cars to keep them simpler. With carburetion, we have certain specifications and guidelines we have to follow.

There are gauges we must have that fit in the venturis, the boosters and the throttle plates -- NASCAR officials check those diameters with go/no-go gauges. We've had some new carburetor rules recently, including requiring us to attach the boosters because we've seen throttle hangs with boosters breaking out of the carburetor and falling down into the butterflies and holding it wide open.

We do some differential float modifications to keep from spilling the fuel over in the corners with the G-forces we have.