NHRA rules want a battery shut-off at the back, in case of an accident, a track official can cut the motor, if driver is injured......
I believe the thought is that now you will have a long hot cable from the trunk to the selonoid, that wouldn't be there with an underhood battery. Look at the Clutch blowup pictures and think about what might happen to that cable.
First off, the battery cut-off is for rescue worker use, in case of a crash, not the driver. That said, I believe the reason for the rule is the assumption is that anyone that is modifying a car to the extent that they are relocating the battery is performing other performance modifications, and thus potentially going fast enough that the car could crash and require rescue workers to respond to it. The track workers need to expect where to find the shut off on any car, thus the rule that it be in the rear (usually towards the right), and a push-off motion. It is also supposed to interrupt the positive cable, not the negative, so it could more easily disconnect any dead shorts that result from a crash.
Never said it was for the driver, but if driver is injured......ie: meaning he(driver) can't shut it off, track crew can...... It's all good I Drag!...
No, no, not meant for you, Sin...the question in the original post was unclear on the intent there. No harm, no foul, bro? (smile)
Safety is the reason. My buddy hit the wall at Thunder Valley at about 140 mph a couple of years back and the track officials wer there almost instantly killing power to the car. Thsi saved the engine which was reving out of control and my buddy from a possible electrical fire. The chassis was a loss but the engine and a lot of other pieces were reusable on the new car. 1600 horsepower engines aren't cheap and neither is the 14/71 blower on top of it. The switch is a pretty good idea in my mind...
I had a short on the amp guage on my 53 Buick and the cut off switch was along side my drivers seat, all cables covered in garden hose. The cable got hot enough to drop out of the cut off switch and kill the juice to the amp guage saving a fire situation. Also it alows you to shut it off for winter storage if you want. They are well worth having especially when the battery is in the trunk. Rags
Plus you can claim in on your car insurance as an "Anti-Theft" device! 15% discount. In all reality ...it is.
A few of the newer sportsman cars I've worked on, had a lever and cable that worked the rear mounted battery switch from the cockpit. The road racing cars have the battery kill mounted near the A post, most are driver accessible. Since the driver is usually the first person at the scene of an accident, I think that is a great thing to have! Craig
A HISTORICAL look at the reasons for the rules would be really interesting... most rules came about in reaction to a nasty accident of some sort. Like for instance the Chevy specific rule that required solid lifter Chevies in stock classes to have scattershields. Some accidents, like Garlits' blowup, really led to wholesale rethinking.
Kurt, the NHRA does not go into justifications for rules. Part of the reason is to keep racers from starting debates with the Tech officials every Sunday morning, and rightly so. The rules are there, and a car is either in compliance, or it's not. To their credit, they discuss the reasoning for new rules in National Dragster, their weekly paper. Most of the rules are there for safety, fair competition, and (my favorite) the continuation of the NHRA itself. Good luck and be safe.
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