| If the reaction time related to when he pushed the pedal to metal when
the
| light turns green? Then if this is so, his true correction for the 1/4
mile
| is 15.3.
Reaction time is a separate clocking. There is no effect on ET.
The reaction timer is keyed to the last amber light (.000).
On a Pro-Tree all ambers light at once and the green lights .400 sec later.
Thus, .400 is a perfect light on a Pro-Tree. A.399 or lower would be a
redlight. A lot of tracks run Pro-trees for their brackets because it
virtually eliminates redlights. However for street vehicles it is very
difficult to cut a decent Pro-Tree light because the vehicle reacts too
slowly to your stomping the gas.
On a Sportsman tree there are generally three ambers that light in sequence
one half second apart. The last amber lights at time .000. The green
lights at time +.500 second. Thus, a perfect light on a Sportsman tree is
.500. A .499 or lower would be a redlight.
When your car leaves the staging beams the reaction timer is stopped and
the track timer is started. There is no connection between the track timer
and the green light. This allows a holeshot win. Lets say Warren Johnson
is racing Allen Johnson's Dodge in Pro Stock. WJ cuts a .495 light and
runs 6.80 in the 1/4. If Allen runs 6.85 (.050 slower) in the 1/4, he can
still win if his reaction time is .444 (.051 quicker reaction). So in the
race both times are in effect added together to determine a winner, but the
two numbers do not affect each other.
There is one additional area that gets confusing. This is advanced stuff
for people running brackets and such. When you stage, there is a certain
amount of distance that your car can go before it actually trips the
clocks. This is called rollout, and is a function of tire diameter. When
staging, drivers talk about being staged shallow or deep. If you are
staged shallow you have driven into the beams just barely activating the
staged bulb. I typically come into the lights with and automatic trans veh
icle with some stall. That is to say my foot is on the brake and the gas
and I have the rpm's raised. I am normally so shallow in the beams that I
can flicker the bulb by raising and lowering the rpms. As I do so the car
pushes forward or falls back just a fraction of an inch and that is enough
to trigger or not trigger the staged beam.
Now if I am shallow staged, I will in effect have a running start on the
1/4 mile. It may be only a couple of inches but that will lower my times!
It will increase my reaction time however. If I'm on a Sportsman light I
have to leave slightly earlier. If I was mashing the gas as the last amber
lights now I may have to go to leaving between the 2nd and third (last)
amber. If I deep stage (still with both staging bulbs lit) I will have the
opposite problem.
Now sometimes you're are forced to run your street car on a Pro-Tree which
I think is really stupid, but they didn't ask me! If you're racing against
somebody in brackets, you need to find out if they allow Deep Staging. In
this context, Deep Staging means you drive so deep into the staging beams
that the pre-stage bulb turns off. If you do this, they will ask to write
with shoe polish "DEEP" under your dial-in. That way the starter will know
when to activate the tree. When you are this deep, the slightest movement
forward will stop the reaction clock and start the track timer. You ET
will be slower by a tenth or more, but your Pro-Tree reaction times will
improve by a tenth or more.
In any case, with a Pro-Tree you see any light at all, you hammer it! It
is a pure reaction to firing of the amber lights. In no case do you ever
wait for Green. I never see the green. I'm leaving on ambers and then its
all a blur!
On a Sportsman light, it's a little different, because you can anticipate
the tree. Since there is a sequence of three ambers a half second apart,
it is possible to red light now regardless of how slow your vehicle is (yes
even if its a Chevy!).
You have to pick a "spot" on the tree to leave and that's based on
practice. Usually on a 15 second vehicle its going to be in the .500
second gap between the second and last ambers. Thats pretty hard to judge
without a lot of practice. Sportsman drivers refer to the lights like they
were flowers blossoming. They will leave at the first "budding" of the
light or at full blossom. A lot of the faster bracket cars have electronic
delay boxes so they can leave on the precise firing of say the first or
second amber and then the electronics "delay" the release of the transbrake
until the proper time to get a near perfect light. You have to set this
delay based on lots and lots of practice.
In categories like Stock and Super Stock where most of my experience is,
electronics of this sort are strictly banned. Still, the performances some
of these drivers turn in are astounding. I once watched my dad run 3
consecutive .501 Sportsman lights during elimination's. Across 7 rounds
that day his reaction times ranged from .501 to .511. On another occasion
he ran 4 consecutive .507's. Almost scary to think about.
Steve Ekstrand, Pasadena, CA Driver: '00 Dakota CC SLT+ 4.7L 3.92SG 255's
Stacey's Driver: '00 Inferno Red Intrepid ES-3.2L-24V Autostick w/Leather
Race Car: 69 1/2 Road Runner 440-6 (ex-NHRA SS/GA future B or C/SA???)
Project Car: 69 Barracuda Notchback (Orig. 318, now 360w/Edelbrock Heads)
Homepage: http://sites.netscape.net/professormopar/homepage
This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 11:48:35 EDT