Line lock and Two step in a clutch car

[Earle Holt]

Thanks guys...I was afraid you'd say that...

With a stick shift car, I don't see what the problem is having the switch on the shifter. It's harder to drive with it there...hooking it up to the clutch pedal looks like a pain! And, everytime you adjust the clutch, it's going to affect the timing of the switch on the pedal?

[Jeff Lee]

Originally Posted by Earle Holt

Thanks guys...I was afraid you'd say that...

With a stick shift car, I don't see what the problem is having the switch on the shifter. It's harder to drive with it there...hooking it up to the clutch pedal looks like a pain! And, everytime you adjust the clutch, it's going to affect the timing of the switch on the pedal?

Exactly. When I ran Stock I had the line-lock & stage RPM on the t-handle. I had a separate button on the reverse lever for the line-lock with a burnout RPM. No toggle switches to arm. The launch was all in my right thumb and left ankle. I'll betcha' one could come up with more funny business with all the wiring on the pedals and behind the dash than out in the open where I had my wires!

[Alan Roehrich]

If you adjust your clutch correctly, you won't have trouble with the switch. And all you have to do to adjust the switch is tweak the "flag" or "arm" a little, which is easily done as well.

Set up your clutch pedal with a stop under it, adjust the switch so that the switch opens as soon as the clutch pedal comes off the stop. When you stage, mash the clutch pedal until it hits the stop. As soon as you start to come off the clutch, the two step will come off instantly.

[james schaechter]

We have an Omron Momentary switch on the pedal. It is the one that everyone sells for about 75 bucks, but can be found on fleabay much cheaper. It is a super heavy duty switch and has an arm with a roller wheel on it. We have it mounted right on the pedal and it deactivates the 2 step when the pedal comes off the floor. You can adjust the switch pretty easily, but I have found that it isn't as picky as I thought it would be. On the racepak, there is no spike of rpm or delay of release off of the 2 step as the clutch engages. You would have to move the clutch pedal a long way to have to readjust it.

I never did understand the concern with a stick car's 2 step. The action that moves the car is the foot release of the clutch pedal. 2 step switch or not, the foot action on the pedal is what moves the car.

[Alan Roehrich]

Originally Posted by james schaechter

I never did understand the concern with a stick car's 2 step. The action that moves the car is the foot release of the clutch pedal. 2 step switch or not, the foot action on the pedal is what moves the car.

An automatic car functions the same. I have no idea where people got the idea that you can release a two step button with your hand and it will launch an automatic car.

If you leave your foot on the brakes in an automatic car and release the two step button, the car won't actually launch, but if it has plenty of HP, it'll blow the tires off. We tried it, just to see if all of the B.S. had any factual basis behind it. No, releasing the two step with your hand won't "launch" the car, and it won't "knock your foot off the brake pedal", either. Even if a car would hook up, and it would launch, the drag on the pedal would be so inconsistent you couldn't get any sort of a consistent launch or 60' time.

Most people know the orange 69 Camaro that Kevin has hooks in a car wash. It may not have the most HP around, but it isn't a complete stone. You can't use a button to turn off the two step and leave your foot on the brake, if you have any hope of the car actually launching. It will sit still and blow the tires off though.

[Sean Marconette]

Per Section 10A Page 11

DELAY BOXES/DEVICES

Two-step permitted. Two-step must be foot activated through brake
pedal, clutch pedal, or pressure switch. Hand release prohibited.

See General Regulations 8:2, 8:8.
ELECTRICAL/CONTROL: 8
8:2 DELAY BOXES/DEVICES

Prohibited in Top Fuel, Funny Car, Pro Stock, Pro Stock Motorcycle,
Top Alcohol Dragster, Top Alcohol Funny Car, Comp, Super Stock,
and Stock; permitted in all other categories (E.T. rules may vary by
division; contact division office). A delay box or delay device is
defined as any device (electric, electronic, pneumatic, hydraulic,
mechanical, etc.) built for the express purpose of creating a delay
between the release of transbrake line-loc, or two-step button, or
release of foot or hand brake, or release of clutch pedal/lever, or
release of any other device and the resultant action of the vehicle,
or as otherwise determined by NHRA.

In categories that prohibit delay devices:

Changeable vehicle
components, legal unto themselves (solenoids, throttle-linkage
components, hoses, springs, etc.), even though the removal and
replacement of that component may affect the reaction time of the
vehicle in relation to the driver action, is not considered a delay
device. Wiring may consist of a single (i.e., “one” or “1”) continuous
wire from a power source to a switch (or button), and a single
continuous wire from the switch to the transbrake or line-loc
solenoid. One splice (no quick-disconnect) is permitted from the
two-step to the solenoid (i.e., between the switch and the solenoid).
All switches, buttons, wiring, solenoids, etc. must be for normal
automotive use; i.e., not intended to create a delay (adjustable or
non-adjustable) between release of the button and the resultant
action of the solenoid. All line-loc/transbrake wiring before and after
the switch must be separate from any other wiring and fully visible.
Computer wiring, sensors, relays, and the like may not be wired to
the solenoid wiring. Two-steps or other rev limiters that are
adjustable by thumbwheel, replaceable chips, and the like may not
be within the driver’s reach and will preferably be located outside

the driver compartment.

Any system that does not fit the above description is prohibited and
must be corrected before the vehicle will be passed through preevent
technical inspection. Further, discovery of a delay device,
adjustable or non-adjustable, at any time following pre-event

technical inspection will be grounds for immediate disqualification


With this rule, the use of the two step became a challenge for stick racers. From a safety standpoint, when depressing the clutch pedal, you could activate the line lock, that would be ugly when shutting down and getting on the brakes, at the finish line! So the way around, is to have micro switches on the shifter, and the clutch pedal. The only time the line lock/two step are activated is when the shifter is in 1st gear, and the clutch pedal depressed. When performing a burnout a separate switch is used to enable the line lock, as typically a burnout in a stick car is performed in 3rd gear. I probably confussed the heck out of this issue!!

Sean

[Earle Holt]

Thanks everyone. I haven't raced in 4 yrs. and when I ran a stick car before, I just had the two step wired to the shifter button...not sure why that's such a big deal now, but I'll just do what the rules tell me and wire it to the clutch. Thanks guys for your input.

Earle