On MANY of the stangs, and other cars, I've seen a manual switch for the fuel pump, no relay, nothing, I will never really understand why? Is there any reason for not wiring into the existing stock harness? It's right there? I have to wire in my external pump, is there any reason I should not use the existing set up? Wire gauge is the same, actually pretty beefy.
If your going carbed .... the pump won't work with out the factory computer when using the factory wiring. Plus even if you left the computer in ... the pump would prime on initail turn of the key ..but the computer will look for an ignition signal from the distributor to keep the pump running which you won't have with the carb set up . My advice ... for what it's worth... is to run a 10 gauge wire from the battery( with a 30 amp fuse ) to a relay and then on to the fuel pump . Then use a keyed ignition source to activate the relay . This is my and probably all it's worth ....... good luck !!
my buddy baisicly did that but w. no relay...he wired it to the fuse box to a 12volt switched source and made shure it stayed on while the key was on..ran it like that for 8months no problems, personaly id do a switch..cuz switches are sweet haha
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and probably all it's worth ....... good luck !!
Looks like I'll be wiring in a relay.
