Hi guys,
I am hooking up an electric fuel pump to my 72 Cutlass S. It has two wires, one positive, one for ground. My question: where is a good place to hook up the positive wire so that the pump is on when key is turned on?
Thanks ahead of time.

 

You need to find 12V ignition. The best place to find that is the fuse box. However, you can also find 12V ignition on the wiper motor.

 

I would not recommend using the wiper motor as a high current feed for a fuel pump. I would run a fused wire directly from the battery through a relay that is controlled by switched power. I would also install either an oil pressure switch or an inertia switch as a safety measure to prevent continuing to pump fuel in the event of a crash. The inertia switch from a Ford Windstar minivan is common in wrecking yards and works well.

 

I alway's take a normal 12v ignition wire like those of the radio.
If it goes on of with ignition key. it doesn't need much of power and you can alway's use or mount a second switch as emergency switch ( as we use it with 4x4 challenge also)

it's the same if you mount a hei (needs also 1 12v ignition wire)
mostly i take a wire that is secured with a 10 amps fuse for safety

We also mount a T (splitter) before the pump so that gas can return in the tank if the carb don't ask for more feul. So the in and return is mounted before it goes true the pump. And it can never overflow the carb.

 

That depends on the pump. Some pumps can't use a return line.

 

That's the RIGHT way to do it.
Although I did not think of the oil pres. sw. or the inertia switch. I guess I'll be adding it soon to my system. THANKS JOE.

You're also better off running a return style system. You will have a constant flow of cool fuel and more stable pressures.

 

This is what I did. On my car atleast there are spare spots on the fuse block that and can slip a connector in for the swtiched power.

 

We also use low presure pumps, high presure for injection type.
Dont know how it works with a 350 or higher but i use it on a 1600 16v and in a 4.2l jeep that runs on liquide gas and petrol. The jeep has a switch to turn between liquide gas or petrol thats the reasen it running with a electric pump.

liquide gas is aboute 40 eurocents and petrol like 95 1,45 euro

do not know if i mount that system on the olds yet

did'nt know there are pumps with return on it, stupid but i never asked for it.

 

I always use the tank vent line (when doing a car w/ a "factory" vent line) f/ the fuel return and get an appropriate vented tank cap. Hook up the pump w/ a regulator and it works well. It really does make a difference when you feed the carb w/ cooler fuel. And if you're going w/ an electric pump anyway, it's not that much extra work. I did this w/ my '81 'Vette only because the stock mechanical pump is hell to get to. W/ the electric pump, it's a breeze, very convenient and left alittle space where the original pump was-any extra space in that engine compartment is welcomed.

 

Gearhead1218 I love the pix of your fuel system set up... I'd love to see more.