Allmendinger, A.J.

Drug Testing FAQ

Some clarifications to clean up the incorrect information circulating around in the wake of A.J. Allmendinger’s failed drugs test. More questions – send them to admin(at)buildingspeed(dot)org and I’ll add them […]

Engines

Pocono: The Shifty Triangle

NASCAR engines like to run at about 8000-9500 rpm (revolutions per minute); however, the tires on the car rotate around 2400 rpm at 200 mph. The gearing in the transmission and the rear end gear reduce the rotational engine speed, with different gears providing different reductions. When you talk about the size of a gear, you’re actually talking about the relative sizes of a pair of gears. The gear on the left in the diagram has 20 teeth, while the gear on the right has 10 teeth, so this gear would be a 2:1, meaning that the smaller gear rotates twice every time the larger gear rotates once. […]

Aerodynamic Forces

Aerodynamic Downforce: A Passing Fad?

The question of why it is so difficult for cars to pass each other at 1.5 mile and 2 mile tracks is getting more and more attention. Carl Edwards put it succinctly:

“I firmly believe, and NASCAR hates it when I say this, that we should not be racing with downforce, sideforce and all these aerodynamic devices. We do not need splitters on the race cars and giant spoilers. I have not been around long enough to say something definitely, but it is pretty common sense: if all the cars are very similar and all the drivers are within a tenth of a second of each other but are relying on clean air and downforce, then by definition if the guy in front of you is disturbing the air then your car is not going to be able to go as fast as it could in clean air.” […]

Cooling

Plate Racing Rules: Getting Ready for Talladega

Most of the issues we were talking about at the start of the year regarding the measures NASCAR has taken to eliminate or reduce the two-car draft are still in play, so I thought I’d put the most important in one place as you start getting ready for Talladega this weekend. […]

Andy Randolph

Kansas Wrap Up: What Caused all the Engine Failures?

The defining characteristic of the Kansas race was the surprising number of engine problems. Many of those problems can be attributed to the change in rear gear from a 3.89 to a 4.00. At 190 mph at a track like Kansas, your wheels make 2270 revolutions per minute (rpm). If you watch the telemetry on the television broadcast, you know that the engine is rotating around 9500-9900 rpm. Since the engine is attached to the wheels, there has to be something to change the rotation rate between the engine and the gears. […]

Cautions

Cautions: A Historical Downward Trend Over the Last Six Years

Being the data geek that I am, I was really curious if the decreasing number of cautions was specific to this year. It’s not: Cautions have been decreasing since 2005,as the graph below shows. The squares are the cumulative number of cautions per 100 miles, obtained by adding up all the cautions in a season and dividing by the total number of miles in the races. (This is a more accurate number than total cautions, given rainouts, shortening races and different venues from year to year.) […]

Cautions

Are Cautions Really Going Down?

I honestly cannot help it – scientists are naturally skeptical. If you make an assertion, I will have to question you on what data you have that supports it. This is second nature to the people I work with, but I realize it is damned irritating to non-scientists (aka “normal”) people.

So when I started reading everywhere that “cautions were down 35%”, I had to go look into it. This is a preliminary post – more detailed analysis will follow as soon as I’ve read my students’ final projects and gotten comments back to them. […]

Browne, Josh

Is Tire Fall-Off the Way to Fix “Broken” Tracks?

There’s been an awful lot of talk recently about changing the layout at various track to make racing more exciting. Bristol is the most-talked-about track, with Bruton Smith planning a $1M revamp of the track to take it back to the way it was before he changed it in 2007. […]

Fancy Gadgets and Short Attention Spans: Is Motorsports Doomed?

Straddling the fields of science and motorsports as I do, members of one community often email me articles about the other community. It’s interesting to see what ‘outsiders’ think is interesting about the other world. Last week, it was a series of articles about how NASCAR’s popularity is waning because kids are too busy playing video games. […]