NASCAR WCUP: Each Week Brings New Test For Dodge Racing Engine
Posted By Terry CallahanMotorsports Editor, The Auto Channel
May 3, 2001
RICHMOND, Va. - The Dodge Intrepid R/T racing engine endured one of its toughest tests during the past weekend at California Speedway. The engine is about to endure a very different kind of test this coming weekend at Richmond International Raceway. Dodge engine builders say the toughest challenge, though, is to design and build engines for the cars and trucks used by consumers.
"California Speedway is very hard on engines," says Ted Flack, head of engine development for the Dodge NASCAR program. "The engine stays up over 8,000 rpm for more than three-quarters of the way around the track. That's a lot of cycles. It's very tough on the valve train."
A two-mile oval with sweeping, banked turns, California Speedway puts a premium on horsepower. Richmond International Raceway, in contrast, is a three-quarter-mile oval that tests an engine's torque - it's hard on the gas, hard on the brakes, hard on the gas, hard on the brakes, and so on. The engine climbs to more than 9,000 rpms before dropping back to about 5,500 rpms in the corners, only to climb up over 9,000 again in little more than the length of a football field. And so it goes for 400 laps.
The Dodge engine development team is confident their work of the past couple of years is up to the task. That's because they used the same discipline, tools and processes they use to develop and build engines for production cars and trucks.
"The requirements of a production engine are really tough," says John Wehrly, who helped develop many production engines, as well as the racing engines currently used in two NASCAR series - the Winston Cup Series and the Craftsman Truck Series.
"Production vehicles need a reliable engine that can be made in high volumes," continues Wehrly. "We build millions of engines, and they must all be capable of going long distances while performing well and be competitive from a cost standpoint. The requirements of a racing engine are different, but the design and development process is similar."
When Dodge announced its return to Winston Cup racing after an absence of many years, the development team needed to come up with an engine for the series. They started with a clean sheet of paper - or a blank computer screen - but there was a lot of Dodge heritage embedded in the fabric of that paper (or Dodge engine genetic code in the operating system of the computer).
The result was the P7-R4 engine used in NASCAR racing today. The new racing engine was designed and developed using the latest in automotive technology, and its roots go back to the mother of all racing engines - the Hemi.
So-named because its heads have hemispherical-shaped combustion chambers, the Hemi was originally developed in 1951. After several years as a production engine and a powerplant for drag racing, the Hemi gravitated to stock car racing in 1964. Richard Petty used it to win the Daytona 500 that year, his first superspeedway win, and the next two cars across the finish line were also Hemi powered.
"That was the best thing we ever had," says legendary engine builder and car owner Ray Fox. In fact, the Hemi engine was too good for the competition and NASCAR eventually legislated it out of stock car racing by imposing weight penalties that made using the Hemi impractical.
While that setback might have discouraged some people, Dodge engineers went to work on other big block and small block engines. Wehrly thinks the rule change was even a benefit to the company because it forced development to focus on other engines and technology. Advancements provided the basis for the Dodge engine used in racing today.
When the Hemi was no longer practical in stock car racing, Dodge engineers first went to work on the "B" block, or big block engines. Later, they focused on the small-block "A" engine. The first A block was introduced in the 1950s. It had a head with a polysphere shape that was designated the "P" head. The P7 head used today is the seventh generation of that development.
"The original A-block engine provided the basis for our current engine from a heritage standpoint," says Wehrly. "While it is a totally modern and completely new engine, it has what we learned in the early days incorporated in its design."
The new Dodge engine has proved it can run well in a variety of situations. The engine started the season by winning the first three starting spots for the Daytona 500. Bill Elliott won the pole with his No. 9 Dodge Dealers Intrepid R/T. Ward Burton led the race in his No. 22 Caterpillar Dodge Intrepid R/T before an accident took him out. The engine powered Sterling Marlin's No. 40 Coors Light Dodge Intrepid R/T to the front of nine out of the first 10 races. And a Dodge engine powered John Andretti's No. 43 Cheerios Dodge Intrepid R/T when he missed winning the season's first race at Bristol by less than half a second.
"The engine we are using today evolved from the small-block engine Richard Petty used to win the Grand National championship in 1975," echoes Flack. "Many of the dimensions are the same - the bore spacing, the deck height, cam and crank locations, the main bearing bulkheads. They are all carryovers.
"One thing Dodge did differently was save the teams a lot of fabrication work," says Flack. "When we started shipping Dodge engine parts to the teams last fall, they were able to prepare four or five blocks each week, sometimes six. They were able to prepare the blocks quickly because we had designed in a lot of the features that previously had to be fabricated after the block was delivered.
Asked to assess the Dodge engine after the first 10 races and more then 40,000 miles of competitive on-track testing, Flack says it is "a huge success - huge.
"We're now more than one-quarter of the way through the season; we've knocked all the big boulders out of the way and we're looking for little bits and pieces here and there," he says. "Everybody's here and we're competitive. We need to get a little better to win. The cars need to get better and the engines need to get better. We've got a lot of new teams involved. We're just coming together."
"We were much more successful at Daytona than we had any right to expect," adds Wehrly. "Our expectations were immediately increased. We're still doing a tremendous job considering the new people, new products and new teams. We're going to win a race this year, maybe two. And I expect Dodge to be even more competitive next year."
This week in Dodge history:
* 5/5/56 - Speedy Thompson captured his first win of the season in the Arclite 100 at Columbia Speedway in Columbia, S.C. Thompson averaged 56.232 mph in his Carl Kiekhaefer Dodge. Buck Baker won the pole and finished second in another Carl Kiekhaefer Dodge.
* 5/3/68 - Bobby Isaac and his K&K Insurance Dodge won the Dixie 250 at Augusta Speedway in Augusta, Ga. Isaac also won the pole with a speed of 83.877 mph on the half-mile paved track. Buddy Baker finished second in a Ray Fox-prepared Dodge.
* 5/4/69 - Bobby Isaac and the K&K Insurance Dodge started from the pole and led all but 17 laps in winning the Fireball 300 at Asheville-Weaverville Speedway in Weaverville, N.C. The win was Isaac's fifth of the season. Second in the race was James Hylton, who started his Hylton Engineering Dodge at the back of the 25-car field because he was unable to make a qualifying attempt.
* 5/2/71 - Buddy Baker moved his 1971 Petty Enterprises Dodge into the lead with 11 laps to go and went on to win the Rebel 400 at Darlington Raceway in South Carolina. The win was Baker's first of the season and fourth in his Grand National career. Dick Brooks finished second in a 1970 Mario Rossi Dodge, and Dave Marcis was third in a 1969 Marcis-prepared Dodge.
* 5/28/72 - Buddy Baker captured his fifth Winston Cup Grand National career victory in front of his hometown crowd by winning the World 600 at what was then Charlotte Motor Speedway. Baker was driving a Petty Enterprises-prepared Dodge Charger. Charlie Glotzbach was third in a Cotton Owens Dodge.
Text provided by Molly Morter
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