Which fuel pump(s) for my 2.5 litre twin-plug ?

[andyjboy]

I've already asked this same question on Pelican but am looking for comments from any owners of twin-plug engined cars as to what model/spec pump they're using.

I am about to install a 2.5 litre twin-plug in my 911R-inspired ('72) car which previously had a high-compression 2.7RS-spec mfi engine.

The 2.5 engine is equipped with 40 IDA Webers & I will be installing new fuel pumps (in parallel) but don't know which particular model is most suitable.

I will be using Facet cylindrical pumps (which look very similar to the late '60's Bendix pumps) with a fuel pressure regulator & in-line pressure gauge - which of these 2 models would be most suitable ?

1) Model 476087 Silver top - 4.0-4.5 psi flow rate 18galls/hr

2) Model 476459 Silver top - 5.0-6.0 psi flow rate 27galls/hr

- or do I need a higher rated (red or blue top) version ?

What diameter fuel hose should I be using - 6 or 8mm id ?

I am keen to keep the installation looking 'period' & have some repro Bendix fuel pump decals (in German) on their way.

I will be using 2 Facet cylindrical pumps mounted as in Ernie W's picture (below) & using the correct-style fabric overbraided fuel hose - probably connected via the brass 'elbow' unions supplied with the pumps (although I may get some NPTF:metric custom addapters made up so that I can use original-type banjo connections) but will probably modify the layout to include a 'circulation' system (as often recommended by Grady Clay) since I still have the mfi return line to the tank.

Any comments/recommendations from existing twin-plug equipped hotrod owners ?

[andyjboy]

Any Weber-equipped twin-plug engine owners care to comment ?

[tomkirkcis]

Hi Andy

The twin pump installation in the image looks incredibly cool, but I do not really understand your question as how it relates to dual plug engines. I do not understand what the type of ignition has to do fuel delivery volume I have seen many large bore twin plug motors with 46's operate just fine on a single pump. Even with the throttle pinned to the floor for a longgggggggg time, I can't imagine a flow rate problem with a single quality pump. Is there a different issue or am I just not understanding your question?

tom