For those who have forgotten to attach their hoodpins and had the hood fly up.

Mike Puckett

SCCoA Member
I just put a fiberglass hood on my drag racer and I know there have been several, myself included, who have had their hood fly open before. So, I decided that I didn't want to have to worry about that anymore. When I attached the lanyards to the pin hoops I skinned the plastic coating off of the wire so they would make electrical contact. I soldered a wire to the other end of each lanyard making sure the wires are insulated from the metal chassis. I fed this wire back to the inside of the dash and connected it to my little circuit.
I used a 4001 dual input NOR gate IC and pulled the input on pin 1 high with a 10K ohm resistor and attached the end of the lanyard wire to this input on pin 1. The other input, pin 2, I connected to ground. The output on pin 3 I connected to the - leg on an LED and the + leg to 12 volts along with 12 volts at ignition on only to operate the IC at pin 14. The ground pin is pin 7. No dropping resistor for the LED is needed. With the hood open the hood pins are dangling and when the key is on the LED lights up. When I slide either hood pin into the hole on the post it completes the circuit and turns off the LED. The pin can't accidentally short to the chassis because it's all plastic up front, no bare metal.
The 4001 is a CMOS chip meaning it can be damaged by static eletricity so care must used in handling it. I would have preferred an old fashioned TTL type chip, a 7400 series, but since I already had plenty of 4001's, I used it. It was also helpful to use an IC socket rather than directly soldering it to my little pc board. It works beautifully. If I start having problems with the chip failing I'll add some bypass capacitors but I don't think that'll be an issue. I can make these pc board circuits pretty easily so if anybody is interested, for $20 I can build them one.
 
Mike,

That is a great solution. Simple, effective....it falls under the "why didn't I think of that" category. :D Good work.

-Rod
 
Just connecting the pins to the lanyard would be a good start. All the times I drove off without the hoodpins they were in my pocket or lying on the workbench.:rolleyes:
 
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