NASCAR taking at least 10 cars to dyno after Michigan race

UPDATE Last weekend's NASCAR chassis-dyno tests — the first of the season — and this week's NASCAR engine-dyno tests of those same motors have been somewhat inconclusive, although Roush continues to say that Toyota has a significant technical edge in engine design.

#2-Kurt Busch's Penske-Dodge showed the most horsepower at the rear wheels in Sunday's Cup testing at Michigan, by a fairly good margin, particularly against Jimmie Johnson's Hendrick-Chevy — maybe 20 to 21 horsepower. But then Jeff Burton's Childress-Chevy apparently won the pure engine tests two days later at NASCAR's Concord shop. The Michigan engine testing was the first major chassis-dyno test of the season. #2-Kurt Busch's car weighed in with 839 horsepower at the rear wheels, best of Sunday.

Now the rule of thumb is that numbers from a chassis-dyno run are about seven percent lower than actual engine horsepower (because the chassis dyno measures output after the horsepower runs through the entire drivetrain). That would mean Busch's true engine horsepower would be nearly 900 horsepower.

Other key Sunday chassis dyno results (unofficial since NASCAR doesn't publicly release the figures, despite a push by several top crew chiefs for NASCAR to release the numbers):

#31-Jeff Burton (11th at Michigan), 830 horsepower.
#8-Mark Martin (sixth), 827 horsepower.
#18-Kyle Busch (race runner-up) 825 horsepower.
#99-Carl Edwards (race winner) 819 horsepower.
#48-Jimmie Johnson (17th), 819 horsepower.
#83-Brian Vickers (seventh), 818 horsepower.
That's a range of 21 horsepower. Winston Salem Journal

08/17/08 NASCAR planned to test horsepower on at least 10 cars after Sunday’s 3M Performance 400 Sprint Cup race at Michigan International Speedway. NASCAR took the Fords of Carl Edwards and Travis Kvapil, the Chevrolets of Mark Martin, Jeff Burton and Jimmie Johnson, the Toyotas of Brian Vickers and David Reutimann and the Dodges of Elliott Sadler, Juan Pablo Montoya and Kurt Busch. NASCAR planned to conduct tests on its chassis dynamometer at the track.