I have an 88 iroc we did a motor swap in. what do i have to use or how do i go about using the fuel pump in the tank. the car used to be a tpi car now we will have a carb. I have searched and read but have not come up with an answer please chime in on what you have done thanks to all on this sight you have all helped me so much.

 

One way is to do nothing and let the oil pressure switch power the pump. That might have you cranking a lot when the bowls are dry, though.

 

i used a 5 psi hobs switch for mine. put it in the same place as the old switch and installed my own relay. looks cleaner.

 

timed relay wired to ign switched, this will give you x- secs (depending on relay or setting if adjustable) pump priming, after engine starts oil press switch will take over. Easiest way!

 

as long as the car never runs out of gas the pump doesnt need to come on till there is oil pressure. the fuel in the bowls will run the car for a while.

 

its been so long I dont remember where it was located, what color are the wires for the pump we stareted this in sept. of 09. we labeled most everything but the pump wires and oil pressure wires

 

Wire the fuel pump to an ignition hot wire.

 

I wired a 12v source (key on) to the fuel pump relay. I think it was a green/white stripe wire. This does bypass the oil sending unit and the pump will run while the key is on. Maybe not the best idea in case of a wreck.

 

Ive got my feed line plumbed to a holley pressure regulator mounted beside my driver's side strut mount. From there the fuel is adjusted to 5 psi going to carb and the other outlet is plumbed to the original return line. When you do this you have to restrict the flow through the return or you wont get enough flow to the carb and the motor will starve at high rpms. I used a small piece of round stock with a small hole drilled through it. Works great.

As far as wiring, Im using an oil pressure switch with a monetary toggle wired up for starting.

 

The oil pressure switch wouldn't save you anyway.

 

So the the oil pressure switch/fuel pump connection only works during start up? So if the oil pressure dropped going down the highway, I would have to wire in a different system to shut the engine off automaticlly correct?

 

Yes, the oil pressure switch was there so that the car wouldn't die if the fuel pump relay failed. It's not an oil pressure safety switch, and it wouldn't even make sense to have one in a fuel-injected car.

 

only reason i installed the hobbs switch is just in case. as soon as no oil pressure no power. plus i can turn the key on after shut off and dont worry about the pump running. like before stated. the fuel in the bowls will get the car started. actually mine will idle for a while with just the fuel in the bowls.

 

I used the wiring from the OPSU, ran it to the old fuel pump relay, added a ground and a hot-in-run - this makes the pump run as long as the key is on.

When I first swapped to carb, I let it run off the OPSU by itself. But - I was stuck for an hour one day when the OPSU went bad and wouldn't run the pump. As a temp fix, I cut the OPSU wires and connected together, making the pump run constantly - until I got it permanently repaired, I would pull the fuse out at the battery to shut the pump off without disconnecting the battery everytime.

 

why not run it off a toggle switch? kinda' like if you were running NOS? This is how I'm going to run my fuel pump when I convert to FI... will use ign as trigger and the toggle switch to control the fuel pump relay... .. this will work right?

 

on my 91 rs i just put in an oil pressure switch for the 3.1 that was in the car and pluged in the haarness wich gave me an accurate reading for oil pressure and makes my fuel pump run when i have oil pressure

 

saving

 

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