| Words and Photos by: Michael “This
is the first time I’ve used Paint in 15 years”
Kent
Where do I start? The past week or so has been
absolutely off the hook! Don’t ask me how
I ended up getting a job that actually pays me to
do this stuff, but believe it or not, Skip Barber
Racing School trusted me with the keys to a 2005
Viper for drifting purposes!. Scratch that, two
Vipers and a Dakota Magnum with slicks. Oh yeah,
and they gave me passes to play with all three on
Sebring International Raceway in Florida. Ohhhh,
times are sweet.
Believe it or not, I went there on business. I
was shooting the last few episodes of Drifting Emergency!
which you will see in the middle of the SCR airing
season. I went down there with one objective; to
learn how to drift a Viper. Well, things didn’t
go so well.
We met up with Erik Jacobs of the DG Trials and
Tony Schulz of Finish Line Racing and jammed the
week up with shooting and drifting on Sebring’s
skid pad and auto cross. Of course, being the producer
of the segment, the heat was on to perform well
with the Snake, but unfortunately, engineering wasn’t
on my side.
Plain and simple, my driving skill was just not
good enough to generate the proper drifting slip
angles with a 3400 lb V10. As I got into the new
Viper, Conrad Grunwald, a Skippy instructor says,
“I know you’re used to a Silvia, and
I have one too, so I know how easy they are to drift.
If you were to put it on a scale of ease from one
to ten, the Silvia would be a one, and this Viper
would be nine and a half.” Yeah, whatever
tough guy. You’re probably into muscle cars
anyways. What do you know about drifting?
Sometimes I should just shut my mouth. I spun that
Viper nearly every run, and to put that into perspective,
we went through about 4 sets of rears… so
I spun a lot. Of course, Conrad The King had no
problem getting the thing sideways, and honestly,
he offered the best drifting instruction that I’ve
ever received. And I’ve sat in with Chunky
Bai, so that says a lot. Ah, who am I kidding? Chunky
tried to teach me how to drift in Japanese, so I
called him a sushi and he kicked my Canadian ass
out of my own drift car. True story.
So why did I keep spinning? Conrad told me some
words of wisdom: Steering Angle and Spring Energy.
The latter, I’m familiar with, as every drifter
should be. The Viper was set up stock with a specific
pound rating of spring compression, to ensure equality
between road and track days. I’m used to this
number being variable in a drift car, and when it’s
set up right, pound ratings can be quite high to
avoid having a ridiculous amount of spring energy
whip you into a spin when you get too hot on one
side. That was only part of the problem, and that
only really affected me when I was doing Feint drifts
(pitching hard to one side and then hard to the
other).
Steering angle on the other hand is a totally different
ball game. I’m used to a 240sx that has an
absolutely ridiculous steering angle; making it
much easier to control. Take a look at any professional
drift car and watch the front wheels. They look
like they’re about to snap off. Reason being,
that such a long turning radius allows for greater
countersteer. I tried looking this info up on the
web, and I found nothing, so I’ll have to
hone my math skills to make this explanation work.
I may be wrong about all of this, but the way I’m
explaining it makes sense to me, so screw it, I’m
publishing it. At 0 degrees (figure 1), the wheel
is perfectly straight and the vehicle is at a standstill.
Now, if one was to turn the wheel to complete opposite
lock, and center of the hub hit a 65 degree angle
(figure 2), it would be fair to say that this car
has 65 degrees of steering angle.
This number can be altered by many things. For instance,
a different offset of the wheel would clearly change
the angle of the wheel, if the measurement point
is the center of the tire. Check the pictures below
to see what I’m talking about (figures 3,
4). A negative offset would push the center line
of the tire over, depending on the offset. Where
our old marking from the center line of the hub
was at 65 degrees, that same center line is now
at 63 degrees, allowing for 2 more degrees of movement
before the knuckle hits its bump stop. So in a nutshell,
negative offset could marginally increase steering
angle, therefore make a car easier to drift. There
are tons of other ways to do this that are specific
per vehicle. For instance, both Tein and JIC make
Tie Rods for the 240sx that have spacers at the
ends of them, again, changing the stock maximum
degree rating by allowing more travel at the same
line of measurement.
Now finally let’s get back to the Viper. It
has 30 degrees of steering angle in stock form.
No, I’m serious. As seen in the Terence Jenkins/Lateral
G interview on www.drifting.com, the Mopar Viper
received extensive modifications to increase that
angle by 19 degrees, however even at 49 degrees,
the Viper was still difficult to control when slip
angle made up the score.
A 240sx on the other hand has about 70 degrees of
steering angle, allowing for greater slip angles,
and easier drift ability. And in a nutshell, this
means a lot less spin out sessions on the track.
But how can steering angle affect your spin ratio?
A spin is induced when the weight of the vehicle
passes over the farthest point of the front tire,
so at 30 degrees in a Viper, you would have a lot
less slip angle than in a 240, which would allow
you to place much more pressure on the outside front,
before the back end wraps around.
Dat’s all me got dis monff. Next month, we’ll
check deeper into the steering hole and look at
the effects of camber, caster and toe on steering
angle.
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