Here is a quote from the article, it is from the "AEM Ford Focus Dealer Package" article, written by Dave Coleman, found at http://www.sportcompactcarweb.com/


"The 16-inch Enkei wheels were a source of confusion at the drag strip. Paired with 205/45-16 Toyo T1-S tires, they weighed only 2 lbs more than the stock wheels and tires, but somehow, putting them on added 0.3 seconds to the Focus' already long quarter-mile time. Eight lbs isn't enough to account for that difference, and even if rotational inertia was considered, the total weight was less than 20 lbs. Coastdown tests on the dyno showed the Toyos didn't have any more rolling resistance than the stock tires either, so we really don't know what to attribute the difference to. The Focus is full of mysteries."


This is weird in that it was the EXACT same thing that hapened to my car! 2 lbs more per wheel, but 3/10ths slower 1/4 mile times!

Why are they so confused? They don't have a clue! 8 lbs. at the VERY OUTER DIAMETER of the tire IS enough to cause a significant difference in rotational inertia, especially in a car with even less HP than our cars, they simply don't know what they are talking about (no suprise there). The tires may not have more rolling resistance, but that doesn't mean anything if the rotational inertia is higher.

Todd Scungio
98 RS
15.803 @ 86.48 MPH