If you blew a 10 on a highway pull, then your fuel pump *circuit* is probably just a hair over 10A, so that the accumulation of heat from extended loading at that current causes the fuse to "slow blow". Even if the fuel pump would pull 16A with a full 13.8 bolts, the resistive losses in the fuel pump wiring at that current level will reduce the voltage across the pump. If you're pulling close to 15A through a 16ga wire, then you likely have pretty high resistive losses, at least for a nominal 12V circuit. If the pump wants 16A, then bumping the wire up to 14ga, or even 12ga if you're feeling extra sporting, would help.Shaun41178(2) wrote: ↑Fri Aug 19, 2022 8:07 am Walbro claims I am pulling around 16 amps or so at the fuel pressure I am running. I believe I have a 20 amp fuse for the pump. I was running a 10, when I first installed it, but it blew that fuse under a 5th gear pull on the highway but was fine for months before that and even Dyno time was fine with a 10 amp.
Regulator is supposed to hold 13.8-14.3 or so, depending on temperature... higher voltage when cold, dropping as it warms up.Shaun41178(2) wrote: ↑Fri Aug 19, 2022 8:07 am But obviously if my voltage is not at 13 volts, then that means I am probably pulling more amps.
As noted, the high current through small wires will reduce the voltage the fuel pump sees.
That's not Ohm's law at all. A constant power load like an AC motor can do that. I'm sure if a DC motor does that. Motors are non-Ohmic devices anyway.Shaun41178(2) wrote: ↑Fri Aug 19, 2022 8:07 am When voltage goes down amps go up right? Ohms law right?
Yeah, you have a bunch of the worst factory wiring still in place. If you're going to upgrade to 14ga or 12ga, you definitely want 280 pins rather than 150. Since the kit Eric posted already uses 14ga, that's a great place to start.Shaun41178(2) wrote: ↑Fri Aug 19, 2022 8:07 am I am using all the stock wiring from the c203. So I have a 30 amp relay keyed off the ignition with a 14 gauge running to the battery terminal c500 location. The relay is behind my driver's seat, and the wire to the pump is spliced into just before the c203, where the aldl connector was at to hotwire test the pump for diagnosis.
So I am running through the c203, running through the bulkhead, going through the pump connector just inside the engine compartment, and then all the factory wiring to the pump hat, and factory wiring inside the tank itself.