Hi everyone, I'm Bob and I'm new to this forum. 

71 base convertible without A/C 

My issue is a #12 black wire with a red tracer on my 71 Convertible. It appears to come from the back side of the fuse block. It has no connector on it. The previous owner had done a LOT of Jankey stuff to the wiring on this car so I am pretty sure its something he added somewhere along the way but before I remove it permenently I thought it wise to ask around.

Thanks in advance for any help in this one. 

Adam's Apple probably has a wiring diagram pdf for your year car.

Welcome to the group. A couple of options for the wiring diagram are the factory service manual which has one and one or more of the aftermarket Corvette suppliers offers one. I don't remember which one though.

I did look on my '72 wiring diagram and I did not see a black w/red coming off the fuse block, or anywhere else for that matter.

Doesn't mean it's not supposed to be there.  Not sure why someone would use a black with red stripe wire to add something to the car.  Usually just use a solid color wire.

Good luck.

Test the wire to see if it is powered, either with the key off, or key on. Since it has no connector, I'd have to agree it is something someone added to the wiring for something, possibly a stereo, or alarm....who the heck knows? I can say with almost 100% certainty it is NOT factory. If it is hot at any time, cut it short, and tape the end up really well, then forget about it.