Recently Jason Fenske
of Engineering Explained calculated a clever theoretical zero to sixty miles
per hour best-of time using the extreme threshold braking measurement. He used
the sixty miles per hour to zero braking distance to calculate the time from 0
to 60mph. The braking shows the grip threshold of the tires. There are some problems
with this. First the sixty foot should be the launch measurement. Second
0-60mph is only half the picture with too many variables and becoming moot with
all-wheel drive.
Real world results of
drag racing with street cars are obtained with the most participatory
motorsport in the United States. Hundreds of drag strips across the country
host hundreds of racers each on any given weekend or evening weekday. Whether
minivans and Honda Civics, Prius or Porsches, and ever-present Camaros and
Mustangs, they are all raced and the drivers get a timeslip with their results for each pass. And on that timeslip is the sixty foot
time showing how good the launch was. The magazines don’t do this. Dragstrips
don’t measure the 0-60mph time. We have a discrepancy.
The 0-60mph
measurement is becoming essentially moot among all wheel drive vehicles. Add
more power and the time drops. With 8, 9 and now 10 speed transmissions, more aggressive
gearing is even easier to make a vehicle quicker without negating overall mileage.
Imagine hitting redline in first and second gear before hitting 60mph in under
three seconds. So for all those AWD performance cars, does a 2.2 or a 2.4 second
0-60mph time really matter? Only in a stoplight race across the intersection.
And assuming launch control is active, conditions are ideal and if an EV, has a
nearly full charge. But a sixty foot time
tells the launch potential. Tesla now has the production car record 0-60mph. And
the new 911 Twin Turbo S lifts the front wheels at launch per Motor Trend. What is the
60ft for both of these?
Rear wheel drive cars
are not just limited to their street tires and a theoretical traction limit
based on their braking distances. Weight distribution and transfer can vary,
that is always a given. But surface and tire adhesion can be increased with
substances like VHT which as a result decrease potential 60ft times. Also a
very popular upgrade for better traction is street legal drag radials (“DRs”).
Dodge is making history by equipping the upcoming Hellcat based Demon with DRs
for the very purpose of better launch traction and hence a quicker elapsed time
at the track.
Footnote:
An initial appeal was originally published on February 3rd, 2013: http://cartruthblog.blogspot.com/2016/07/what-car-magazines-should-measure-part.html
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