Wiring Orig. Fuel Pump to 350 Carb motor! Help!?!?
Wiring Orig. Fuel Pump to 350 Carb motor! Help!?!?
Im trying to figure the wiring and the fuel lines to regulate the psi to 6-8psi using the original fuel pump in the car going to a Carbed engine. Curious if anyone has messed with the similar situation. Im just confused with the fueses and the relays. Powering the pump and all.. please help! Thanks guys!
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From: Mattoon Il.
Car: 1989 IROC-Z / T-Top -1987 GTA
Engine: 305 (LO3) _350 (L98)
Transmission: 700R4 _ 700R4
Axle/Gears: 2.73 L.S. - ???
Re: Wiring Orig. Fuel Pump to 350 Carb motor! Help!?!?
the oil pressure switch is part of the system, make sure that is hooked up ... i know everyone says you need a regulator, but when i did my tbi to carb swap i just used a filter with a 2nd outlet and routed it to the return line ... never had a problem with it
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From: Ohio
Car: 1987 Trans Am
Engine: 305 TPI
Re: Wiring Orig. Fuel Pump to 350 Carb motor! Help!?!?
You may be able to get away without a regulator if your car was a tbi because of the relatively low pressure but the tpi fuel pump puts out a much higher pressure and will not work without the regulator and return
Re: Wiring Orig. Fuel Pump to 350 Carb motor! Help!?!?
*And about that fuel pump, I know the TBI fuel pumps run about 12psi - straight from the pump- so I figured I would send it down to about 6-8psi. Not sure if its bad for it to be a little high? Who knows, but i'm just going off of old hot rod notes from back in the day haha.
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From: Western NY
Car: 88 convertible
Engine: 5.7L
Transmission: 4+3 maual
Axle/Gears: 3.07
Re: Wiring Orig. Fuel Pump to 350 Carb motor! Help!?!?
Look at this diagram. You need to jump the orange wire to the tan/wht wire at the fuel pump relay. This will run your pump whenever your key is in the run or start positions. As far as the fuel pressure regulator, use one. You don't want over 6 psi going to the carb as the needle and seat is not designed for that high of a pressure. You may get away with it for a while but as the needle and seat wear, you will start pushing fuel past and flood/wash down your engine.
Re: Wiring Orig. Fuel Pump to 350 Carb motor! Help!?!?
^ Thats great if you want to test the pump function or drain the tank. It is NOT useful for continued use ie driving
Lets keep it simple. The relay is computer controlled and since the computer is removed, just replicate what the computer would do to command the relay. In this case, add 12v IGN to the DK GRN/WHT wire and you're done
Lets keep it simple. The relay is computer controlled and since the computer is removed, just replicate what the computer would do to command the relay. In this case, add 12v IGN to the DK GRN/WHT wire and you're done
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iTrader: (1)
Joined: Dec 2012
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From: Western NY
Car: 88 convertible
Engine: 5.7L
Transmission: 4+3 maual
Axle/Gears: 3.07
Re: Wiring Orig. Fuel Pump to 350 Carb motor! Help!?!?
Yep, your right. I saw the hot in run and start and figured that was ignition but didn't give the bulb test a thought. oooops!
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Re: Wiring Orig. Fuel Pump to 350 Carb motor! Help!?!?
Look at this diagram. You need to jump the orange wire to the tan/wht wire at the fuel pump relay. This will run your pump whenever your key is in the run or start positions. As far as the fuel pressure regulator, use one. You don't want over 6 psi going to the carb as the needle and seat is not designed for that high of a pressure. You may get away with it for a while but as the needle and seat wear, you will start pushing fuel past and flood/wash down your engine.
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Joined: Oct 2015
Posts: 9
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From: Missouri
Car: 1989 Camaro IROC-Z28
Engine: Built 5.7l
Transmission: 700r4
Axle/Gears: 2.77 posi
Re: Wiring Orig. Fuel Pump to 350 Carb motor! Help!?!?
my relay has no green/white wire please HELP!! 89 iroc 5.7 tpi converted to carb and ECM removed. Sorry for hijacking thread btw
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RAYS87TURBO
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