It this a direct swap? Will the in-tank fuel pump fit in an 84'?. what elst besides a pressure regulator is involved?

 

TPI requires 40-47psi, a carb fuel psi can be as low as 6psi so no you can't use a TPI fuel pump, but you can replace the TPI with a TBI (15psi) they are physically the same, you'll have to use an adjustable fuel pressure regulator to dial the pressure down to 6-10psi depending on the 350 carb requirements.

 

I ran a Waldron 255 with adjustable fpr and a carb for nearly 4 years. You can do it but requires some work that may be more difficult for you then changing your fuel pump




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I am pretty sure that the sending unit will directly swap. I plan on using a fuel pressure regulator to limit my pressure. So an aftermarket fuel pressure regulator wont be able to limit the pressure to 5-7 psi? I am sure that the wiring will be the fun part.

 

TPI sending unit was a direct swap on my 85 which originally was carbed. So on your 84 it should be the same as the tanks didn't change. The only thing different are the fuel fittings to the car. The TPI unit uses the o-ring high pressure fitting where the carbed unit is simple a barbed end that a rubber line clamps to.

Here is a pic of the carbed unit next to the TPI unit. Hope it helps.

 

To answer your question, yes you can just drop an EFI (TPIorTBI) sending unit with pump into a carb system. The sending units for fuel level are all the same resistance so the gauges will work. However you will have to use a By-Pass pressure regulator in the system so that any fuel over the required pressure/demand is sent back to the tank to keep the fuel pump from getting overworked. I know my 86 LG4 had a fuel return for the mechanical fuel pump that can work for a return line for the by-pass regulator if the flow isn't too much for the lines diameter.

I don't know why you would want to install a TPI pump into the tank if you already have a carb system to start with. Are you worried about fuel starvation from the mechanical pump? With higher performance cars factory fuel lines can also become more restrictive for fuel delivery.

Most people only stay with the EFI pumps because that was already on the car to begin with and don't want to drop the tank to replace it with a carb style pick-up and mechanical or in-line electrical fuel pump.

 

This will actually go into another post later, but I want to eventually install a remote starter/turbocharger setup. The electric fuel pump would allow the carb to be primed for a cold start (I think). I also want to eventually swap to a TBI, TPI, or EFI system.

 

The only thing you will be doing with an electric pump and a carb is filling the fuel bowls up.

"Priming" for a cold start is usually done with a foot pressing on the gas pedal a few times.

Keep the mechanical pump until you are ready to step up to the turbo or EFI which ever comes first