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what fuel pump pressure for EJ18
mark-s - April 11th, 2006 at 07:56 PM

Hi

I have a EJ18 from a 1991 Subaru Legacy. In the UK, cars from that year came with a Hitachi carb. I think it's the same carb as used on EA81 & EA82 engines.
Does anyone know what the fuel pressure should be? I'm currently running a 9psi pump, which seems to work ok, but is it right?
Also, there is an outlet on top of the carb float chamber which goes to the swirl pot. I don't understand what this does exactly. I can't see that fuel would get to it unless the float chamber flooded! There is a return from the swirl pot, which I have plugged at the mo, but presumably i could connect this to the suction side of the pump, like the regular fuel return line.

If anyone has had experience of this type of carb before I would be grateful for input.

cheers


555bug - April 11th, 2006 at 09:29 PM

ok I'm no expert but sub 10psi for a carb should be fine, i did some side draft 45 on a golf on 6psi and she seemed happy just keep in mind you ar e only getting fuel to the float chamber so psi is not critical as long as its getting enough to maintain the engine hp (hate to find out by running lean at WOT) as you suspect the return from the float is there as the pump is on continuiously so there needs to be a mechanism to deal with this fuel or you will stuff your pump.