Aerodynamic Forces

Drafting: Regular and Bump

I looked through the blog and realized that I haven’t really blogged about drafting. I’ve blogged about all the rules NASCAR’s enacted in the last couple of years to try to control drafting, but not drafting […]

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Aerodynamic Forces

Does Less Downforce Mean More Lift?

Last Tuesday, NASCAR announced aerodynamic modifications to be implemented for the Kentucky Speedway Sprint Cup race on July 11th. While the changes are (right now) only for that race, there’s every expectation that if they help […]

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Aerodynamic Forces

Firewalls and Aerodynamics

My friend at the Milwaukee Journal Sentinal, Dave Kallman (whose online column should be a regular read for race fans) asked about the confiscated firewalls from the Number 11 car at Indy. That reminded me of the first NASCAR race I was supposed to attend as research for my book The Physics of NASCAR. That was California in 2007. I was to follow around the number 19 car, at that time driven by Elliott Sadler and crew chiefed by Josh Browne. […]

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Aerodynamic Forces

How Fast Would NASCAR Cars Go at Daytona without Restrictor Plates?

Doug Yates was guest on Dave Moody’s SiriusXM Speedway last week. He brought up a conversion you hear a lot in the week before Daytona and Talladega. Every 25 horsepower in the engine translates to about a 1 second decrease in lap times. Dave did the math: Removing the plates would increase the engine by 450 horsepower. Four hundred and fifty more horsepower equates to 18 seconds off the lap time, assuming all other things equal. That last part was a very important qualification. It will come back to haunt us in a moment. […]

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What’s a NACA Duct?

The words “NACA Duct” usually go by so fast that they sound like “Nackaduck”, but a NACA duct is really just a specialized type of duct. Ducts are hoses or other devices used to move air from one place to another. brings air into (in our case) a racecar in a very special way. Clear NACA ducts can be seen in the rear windows of NASCAR cars – there are usually two or three in the window. Carbon-fiber NACA ducts sit in the front of the car. […]