Bob Spindel

I'm in the process of rebuilding a '77 CIS engine that I plan to install in a '73 that has MFI, not CIS. I understand that unlike the MFI fuel pump, which is mounted near the left rear tire, the '77 fuel pump is mounted up front near the fuel tank. Is there any reason for me not to mount the CIS pump near the old MFI pump, or in the engine compartment itself? It seems like it would be easier.

(I am assuming that I actually do need a new fuel pump. The MFI pump doesn't have the right specs for CIS. Right?)

Thanks for your help. And forgive me if I have screwed up someohow in posting this. Although I've been posting to the List since its Porschephile days, eight ot nine years ago, this is my first shot at a discussion board.

Bob Spindel

Bill Gregory

Hi Bob,

Welcome to the 911 board - don't hear the site "Porschephiles" much any more - I was there too.

You're right that the CIS pressures and MFI pressures are different. CIS is higher - there's no belt-driven MFI pump pressurizing the system. One reason not to mount the fuel pump in the back is heat - exhaust or engine compartment. The CIS pump is a roller cell (If I remember correctly) that relies on fuel moving through it to cool it. Plus, it's almost a gravity feed, as I recall, from the tank to the fuel pump (over all of it's 6" of connecting hose), and it'd be tougher if the fuel pump was located in the rear. There's a bracket with rubber isolators that holds the pump in front. Part numbers are:

77-79 Fuel pump 911.608.102.00
Suport bracket 911.608.105.00
Two rubber bumpers 911.608.206.00
Hose clamp for pump to bracket 999.512.394.00
2 hose clamps and 1' (cut to fit) fuel hose for connection between tank and pump

The fuel line out from the pump would need a new banjo fitting to hook up. Or a new pressure line, 911.356.066.07.