that page was from 1989 back when installing engines was the norm for many dealers. Notice it still reports NO WING NUT CONNECTIONS even for carb engines. More info --- for EFI engines that is one of the worst things one can do for battery connection is use wing nuts.

the guide lists solder for the battery terminal / connection --- we do not use solder anymore period or I should say I do not nor will.

I'm putting ends on them myself so ordered proper 3/8 and 5/16 lugs for switches, batteries, and starter.

so 9 1/2 to 12 ft requires 2/0 or 00. I get that 2 and 2/0 are VERY different. I'm way past considering using 2. I was told by a cable manufacturer that the length has to consider both the postive and negative round trip. So, if you have 6' from your battery to your starter (including the trip to the switch) and 6' from your block back to your battery, you are at 12'. I'm no electrical engineer but that is what I was told.

I'm re-rigging completely so no real restrictions. Just weight and ease of managing the big wires. 4/0, which was suggested on this forum (not this thread) is HUGE! I guess I'm going with 2/0 and I should be quite safe. I'll minimize the lengths as much as possible.

Appreciate all of the insights.

2 or 2/0? Wow, if a 35 fountain can get away with 2AWG and I'm running 2/0, I'm WAYYYY overkill.

All mine were 2 . I had to use use both batteries to start one engine. It would struggle just using one. But cig put a parallel switch in there to temporarily connect the 2 batteries while cranking so it worked fine for years.
I`ve always had started issues thou, my flywheels are now stripped in a couple places .hoping the wire upgrade will help .

I got all the stuff and went with 2/0. Yes, quite big. If I was ordering again after seeing these I'd go with 1/0. Hey, these cables match everying else I have done the the boat -overkill. Go big or go home. Now I need some more horsepower to make up for the 50 lbs of battery cable!

Thanks to all for input.

Ive been custom making my own for yrs.

You will love the looks of the finished product. Crimp tools are too cheap to not do it.
Will now match the quality of the rest of your project.
I use good heat shrink too. It is thick tubing w/sealer in it that flows once heated.

Im thinking Im going to end up w/my batteries in the cabin which I dont like.
W/all the extra fuel Ill now be carrying, and that addition being aft, and the garage Ill now have where the motor used to be........., and all the crap that will find its way in there......., yikes : )
I think our folding bikes are 30+ lbs a piece.

i would still go with tin plated on anything,when you see older cable that the brass has turned dark/green even up into the wire where you wouldn't think that oxygen would get to, also don't skimp in the heat shrink, prowire on ebay sels the buttery quality stuff in smaller quantities

https://cimg1.ibsrv.net/gimg/www.off...7417ed731d.jpg

ck out seawire in alibams the Tefzel m22769