I'm in the process of installing a 2.7 -6 in my white car. Was planning on moving the fuel pump to the front trunk to avoid the vapor lock problem I experienced on my trip last year. But with the CIS system requiring a 150 psi fuel pump, I'm not sure I want that high of pressure running through the car.

Even if I did put it in the front, should I change the SS pressure line to a threaded fitting line, or mount the pump on the firewall in the engine bay?

What have others done?


Thanks,
Jeff

74-75 maybe 76 911's CIS have pumps mounted in the rear, Keep it low Gravity is your friend....and away from heat..

the ss line with a AN fitting would be nice but it depends on where you have space. and my advice would be put it somewhere easy to access.
for me it would be the front.

Yes, Put the SS lines in!! If it was me, I would cut the front firewall and install the 75/76 pump mount so you can get to it from the trunk! If you do it right you can pull the pump into the trunk and change the pre-filter from there!

Thats what I did!

That's what I did, I have SS lines already, the holes cut and I have a 75 cover and bracket, but now I'm wondering about the pressure, is hose clamps enough to the SS lines or change to -an fitting lines, or mount the pump in the rear ?

150 psi just seems like a lot to just use hose clamps

Jeff

I guess this thread is my fault. I was at Jeff's and looked at the pump mounted up front and questioned how he was going to safely connect the high pressure output from the CIS pump to the engine.
The SS line thru the tunnel is plenty strong but can he clamp a rubber hose from the pump onto the SS line and hold the pressure a CIS system operates under (70-80 psi system pressure). And then clamping a hose to the other end of the SS line going up to the CIS fuel distributor? That is a lot of pressure for clamped hose connections. All the stock CIS line fittings are threaded.

I've done similar conversions on 911's (Carb'd Eng to CIS) and used braided SS hose with AN fittings but running it thru the tunnel is a pain and I think 911s have a bit more room in the tunnel.

If my memory serves, the 911s that had CIS & a front mounted pump from the factory had a high pressure plastic fuel line thru the tunnel with banjo or threaded fittings factory installed.
Jim

Yes or at least secure connections that are NOT hose clamps. The CIS fuel systems I've seen have banjo bolt connections and "threaded connections" like/similar to flare fittings

Pump puts out 75 psig. Control pressures range from about 45 - 55 psig.

I used two extra wide solid, non-slotted, hose clamps per connection. Each connection has a small bump on the SS line to hold the hose from being pushed off!

If I had it all to do again I would use some type of Banjo fitting to AN and have the AN connectors added to the SS lines!

I can weld AN fittings on your lines.

Problem solved, I'll add it to your list.


Jeff

Dude, right on!