Re: Stewart's 1955 Packard 400

Posted by HH56 On 2015/11/25 10:45:11

I'll throw in a wire size calculator I've used on a few occasions so you can have an even 16 opinions.http://www.gtsparkplugs.com/WireSizeCalc.html

If the motor does as Packard says then 14ga for a 5' run would be marginal but adequate in delivering full current and voltage. The 55 TL was fused at 20 amps and Packard mentioned in an early bulletin the motor would pull approx 17 amps at load. No mention of how much if any voltage drop. I believe in some cases that 17amps was found to be optimistic and reasons for reports of fuses blowing were listed. In 56 they went to a 30amp fuse (brake lights were added to that fuse which accounts for some of the extra) but I believe there were no further fuse issues after changing to 30 amps.

Even though max capacity is needed in very short duration I think I would use 12ga in that particular red feed wire just to have a margin over. 16ga is fine for the others because the runs are short and current is low on two of the wires. 16ga in the 18" or so distance between the solenoids and motor can easily handle 20 amps and still deliver full voltage.