Ask the Best & the Brightest: How to Measure Bang For The Buck?

For budget minded leadfoots Forbes came up with a list of the ten quickest cars that cost less than $30,000, based on performance data measured by Edmund’s InsideLine. You can go over to Ray’s place to check out the list in greater detail or Forbes for the original version, but the list got me thinking. Can you derive a metric from performance and price information that measures “bang for the buck”? When cost is not much of an issue, performance is a given. High performance at a lower price point, though, is as worthy of note as high buck supercars. I’ve always been partial to products that provide a large fraction of state of the art performance at a small fraction of state of the art prices. The question that I have when it comes to fast cars is: is there a way to come up with a statistic that realistically models performance per dollar?

I decided to multiply the 0-60 time by the MSRP, take its inverse and multiply by 100,000 to get a decimal fraction like a batting average. Like a batting average, a higher score is better and I decided to call that stat BFTB, Bang For The Buck. I think it accomplishes what I’m trying to do: a more expensive car with the same speed has a lower BFTB but a cheaper car that isn’t quite as fast, might have an equal or better score. A hypothetical $30,000 four second car would have a BTFB of 0.833, the same as a $24K car capable of a 5 second run. The BFTB stat also would reward a more expensive car, if that expense translates into a significant increase in speed. To a point. As cars approach six figures, BFTB nosedives even though there’s some very serious speed involved. You might say that the BFTB disfavors some of the fastest cars on the planet. I say that it shows just how expensive incremental improvements in speed can be. Of course, the people who buy those very fast cars are the folks who aren’t exactly looking for bang for the buck.

I asked TTAC’s house statistician, Michael Karesh what he thought, and he suggested that BFTB might need a log function in there somewhere. I’m guessing that because in real life a low time is preferred, and also because when you plot out 0-60 times the curve starts approaching an asymptote somewhere south of 4 seconds, there’s already a logarithmic or exponential function involved.

Above is a table with the cars ranked from highest BFTB to lowest. I added the Chevy Camaro that Jalopnik noticed was missing from Forbes’ original list. For comparison’s sake, I also ran the figures on the ZR1 Corvette and the Bugatti Veyron. By that standard, the V6 Mustang is the BFTB champion. The Subaru Impreza WRX comes in second. The Mustang GT may be faster than the V6 version of the pony car, but you end up paying $7,000 more to go 0.8 seconds faster to 60 mph. If you want to calculate BFTB yourself, I posted a spreadsheet that you can download here.

I suppose you So I’m throwing it open to the B&B: how would you measure the most efficient expenditure of performance dollars?