better to run an independent wire from alternator to a 30 amp automotive relay to fuel pump and use the stock fuel pump wire or similar to trigger the relay.

Was going to run it to the battery....is there a difference? Was going to go to the battery so I wouldn't have to tear apart the wire job I did to alt/dizzy/coolant sensor...:)

hook it up to the engine fuse box @ 80amp terminal

What's to stop the fuel pump from running in the event of an engine stall? Or worse, an accident. I never did understand carbs or older cars... :dunno: On a car with an ECU, if there is no RPM, the pump does not run.

you can always install an oil pressure switch between the ignition and relays trigger. IIRC its made by holley... no pressure no fuel pump

80AMP terminal it is!

So I hooked up relay to fuel pump....to get direct power to pump....same issue. No fuel pressure once car starts. I've done the search....to no avail. Anyone know which two wires (positive/negative) to pump? There is the pigtail with four wires....I haven't been able to find which two I need and I don't want to lose the gauge if the other wires operate sending unit.

are you saying fuel pump turns on but looses pressure when engine is running?

It looses voltage once it fires....thought it might be due to eliminating some of the fuel injection wiring. Was thinking of just wiring it straight and putting it on a toggle switch.

just run a toggle switch to control the relay for now. ignition wire so it will be off without the key. what brand/psi pump are you using?

Factory pump...Mallory 4309 regulator....I was planning on the relay....but through the factory wiring...it does the same thing as before I ran the direct power wire...so I was thinking just power and ground to pump..

PSI I am setting at 4...

Anyone have the designation of the wires on pigtail for pump? I think they are Red, Black, Black/white, black/?.....just looking for some help with direct wiring to pump to get this thing fired up....Diagram I found said to do this:

Cut white/red wire on harness to splice in the relay (30 side), splice a ground wire from black wire, to ground for opposite ends of the relay of course....but no on power...still quits. Assuming I just need to eliminate the factory wiring to the pump pigtail. Correct me if I'm wrong on any of this please.

when you ported the exhaust, did your motor heave the exhaust flow channels?

and if so how far did you take them down?

The motor was already built...but they were removed...nice huge opening...:)

Can't get no love on the forum? No one has ever put a toggle switch on factory pump without using a relay? Four wires on pigtail....should only need two...

alternator-fuse-#30 relay
87 or 87a-fuel pump
86-ignition 12v
85-ground

Got the right info thanks to Siraniko....big props! Hope tonight is the night to finally break in new motor and go for a spin!! Any quick tips on how to post vids from phone?

Got it figured out!!! FIRED UP!!! This thing sounds nasty!! One more hour of break in and need to get a better throttle set up....want to try and figure out how to load a video too.

For anyone looking for wiring straight to pump....looks like its the SOLID black for ground....and black/white for power. Thanks for all the help Siraniko!!

Good to hear its running now :icon_tup: As for uploading a video, you can use Youtube's app for your phone. You can upload the recorded video straight that way. You can also just plug your phone into a pc and upload from there as well.

Would love to see some close up of throttle linkages. Found the Systec, the Weber over carb/under carb....anything custom out there to get to WOT successfully? SHOW ME WHAT YOU GOT!

i made this simple but effective throttle cable bracket for my sons fb with 48dco which is similar to yours. goes on top of the inspection plate

as a temp fix use an alternator or smog pump bracket

Does the hole location need to be parallel to the elbow on the carb? Seems like to get to WOT it would need to be below?...