Hard start question

[dave`12]

Here you go:


all cranks are for 5 seconds.
unhooked power to HEI

beginning btty volts 12.67
btty post to post cranking drops about 1 volt

leads of multimeter: + btty to starter main line 000
" " cranking .25 (so 1/4 volt loss)

leads btty - to starter case .2 loss
" " cranking .25 loss

This was done cold.

These tests were done with my old battery, a cheap one at that. I've since upgraded to a new optima red top and upgraded the 4 guage wires to 2 gauge, so the numbers could well be better now. I also moved my ground from the alternator bracket to the engine block.

I've got some other stuff apart now, so I haven't tried running it hot and trying to start. Hopefully I can get to that in a couple of days.

I really think the issue is headers that are no more than an inch from my starter. I bought some header tape, but want to see what happens after my latest changes before breaking open the package, I'm hoping I can return the stuff, it was not cheap.

These are the headers: https://www.summitracing.com/parts/s...del/c10-pickup

If it's still bad, I may well return the header tape and just get ramhorns. I live in south florida, and the summers will be hot.