Well it is about time! Lexus finally released the official Japanese domestic market specifications for the much heralded but statistically challenged warrior from the land of the rising sun. Now finally all of the arm chair racers of the world can speculate just how good the IS-F really may be. We can already hear those dismissing the IS-F as underpowered and too heavy, and on paper is may actually seem so.
Until you piece together the fine print that is.
While we might just be a few months away from an actual side by side comparison of the established Uber sedans and the new kid on the block. You need to be aware the IS-F may be coming to this shootout with an ace in the hole.
Several years of racing have taught me to never underestimate the competition, because when you do, you will get beat. I also learned that while many of the finer points of racing are skill and finesse, most of it can be scientifically calculated with a reasonable degree of accuracy. You can easily surf the web and find simple a calculator that promises to magically perform these tasks just using horsepower and curb weight to estimate a 0-60 or ¼ mile time. But my experience shows it is quite a bit more complicated than that. You have to compensate for torque, tire grip, and gear ratios and other factors.
After searching through my endless archive of software I whipped out one of my racing tools I have used in the past that estimates and analyzes performance and considers the following:
Horsepower @ what rpm , Torque @ what rpm, Tire Size and Profile, Final Drive Ratio, Transmission Ratios, Redline, Curb Weight, Wheelbase, and even Aerodynamic Drag,
Taking this data and other factors in to consideration it is possible to optimize launch point shift points and obtain a theoretical best effort. Using these results we can potentially obtain a theoretical comparison. Most car tests are now measured using computerized in car accelerometers instead of a fifth wheel device, but since we don’t have an example IS-F to test we can use the math. After all Newtonian physics really haven’t changed the formulas, technology just allows us to measure them more accurately.
Now all of this sounds great on paper, but does this really work? Pretty darn well as I found out and the results made me go back over the scenarios over and over again.
After obtaining all of the required data from the manufactures websites I entered in two benchmarks, to test the results. The 2007 RS4 and the 2008 BMW M3 both had recent tests published, and these gave me an idea if I was going to be accurate. As expected, I found the results were extremely close, and nothing was way out of the realm of reality.
The M3 was recently tested by Car and Driver in September and was found to perform 0-60 and ¼ mile times of 4.8 and 13.2 seconds. My program calculated 4.85 seconds and 13.2 respectively. Pretty scary, but was it a fluke? The RS4 also proved to be equally accurate, with the car testing at 4.9 and 13.2 seconds, and the calculated results indicating 4.9 and 13.2 seconds as well. This was pretty dead on, and about as good of a benchmark as we can expect.
So then I tossed in the upcoming 457hp 2008 Mercedes Benz C63 AMG as a wild card. What a beast. The advertised 0-60 is quoted at 4.5 seconds, and my calculations indicated 4.4 seconds and went on to predict a ¼ mile of 12.70 seconds as well. Very impressive and again confirming a degree of accuracy. I also threw the rumored 450 hp Audi RS4 just for giggles.
Now for the moment of truth. In went the Lexus IS-F data, more weight than the M3 and even less horsepower, a forgone conclusion right? You might think so, until you look at the gear ratios and the spread. It seems two more gears can make a heck of a difference.
Expecting the quoted 0-60 time of “less than 4.9 seconds” I was absolutely floored to see the program kicked out a 0-60 time of only 4.4 seconds. This was faster than the quoted time for the C63! Looking over to the ¼ miles I found I got 13.0 seconds flat. Only in the final few feet did the IS-F get beat by the C63 .
Well my friends, I have to admit, that me, the biggest Lexus pessimist in the world just learned on paper that Lexus had an ace in the hole those extra two gears. The lower first two gears allowed the torque to multiplied better and be applied in a more linear fashion to the pavement. Torque as most of us know, governs just how hard you accelerate and only further down the line horsepower takes over. The higher torque of the Lexus 5 liter and better gearing combined translated into one of the fastest 0-60 times and the second fastest ¼ mile in the calculations.
We will only know what the real life results will be when the cars are actually tested over the next few months. But in this scenario, using factory supplied specifications the results are pretty conclusive. Lexus may have placed a notch in the belt at the expense of a few our more pedigreed marques.
Below are the results of the software calculations:
Calculated 0-60 Times
4.4 secs. – 2008 Lexus IS-F
4.4 secs. – 2008 Mercedes Benz C63 AMG
4.7 secs. - 2008 BMW M3
4.8 secs. – 2008 Audi RS4 (450hp est)
4.9 secs. – 2007 Audi RS4
Calculated 0-100 Times
10.3 secs. – 2008 Mercedes Benz C63 AMG
10.5 secs. - 2008 Lexus IS-F
10.8 secs - 2008 Audi RS4 (450hp est)
11.1 secs. - 2008 BMW M3
11.3 secs. - 2007 Audi RS4
Calculated ¼ Mile Times
12.7 secs. @ 112.60 mph - 2008 Mercedes Benz C63 AMG
13.0 secs. @ 110.10 mph - 2008 Lexus IS-F
13.2 secs. @ 110.60 mph - 2008 BMW M3
13.2 secs. @ 108.20 mph - 2008 Audi RS4 (450hp est)
13.4 secs. @ 106.70 mph - 2007 Audi RS4