hey guys im in the middle of installing my powerjection 3 on my 71 chevelle with a 496. the instructions say to mount the fuel pump below the fuel tank within 2 feet of the tank. my problem is i can find a good spot to mount this thing! does anyone have any suggestions on electric pump placemnt? also why do the instructions have these specific parmeters for pump placement


also are the tanks in these cars vented? because it says it needs that too

All tanks are vented in one way or another. On a '71, if you have a stock tank, you will have the improved evaporative venting setup. If it is all there and semi-intact you should be fine on that account.

The fuel pump needs to be close to the tank and such because of the design of the EFI pumps, they do not suck fuel well if they are working on air. Much less critical once they are primed with fuel. Then they will work great. But once they get air the suck goes away (or at least WAY down).

the fuel pump needs gravity feed. it can be at the level of the sump and still gravity feed. as long as the pump is below the top line of the fuel level, it will gravity feed, so you have some leeway

on my car there are three lines coming out the middle of the tank going into a crossmember from the cross member they split off so im wondering if someone has a diagram that shows what line is what

The key is the gravity feed as said. You also want the pickup to be low in the tank and very preferably baffled. Sumping the tank (safely) is the best way to go.

just want to get the groups seal of approval. the only place i can see to mount this thing is on the frame rail 3-4ft away from the tank but the pump would be below the tank thus allowing it to gravity feed. other than that i could mount it where the vapor seperator is which would be closer but that would be above the tank...i think i am making this harder than it should be

I ended up putting mine on the back side of the rear finish panel. Here's a pic of the mockup:
http://i168.photobucket.com/albums/u165/Bowtie-Bry/TECH/DSC03275.jpg

Is that your return line going into the filler neck? If so how is that working for you?

Yep. Works very well. I fugured that was plenty high and flows into the top without adding any cavitation or anything. When I had the sump welded in, I had him put a bung in to accept the return line. I run both lines side by side up and over the wheel well and along the frame just like stock. I used insulated clamps doubled up and drill tip screws into the frame.

http://i168.photobucket.com/albums/u165/Bowtie-Bry/TECH/DSC03273.jpg

One more question, is that a vent line higher up on the neck? Looks like it, but I can't tell for sure. Fixin' to start on EFI conversion on my '65 Tempest, lookin' for info. Thanks!

Not a vent line. Mine has only the return you see plumbed in, and then it goes farther up to the gas cap. The black filter you see now has a blue hose coming off and to the sump. The vents on my 72 are all at the top of the tank and forward.

I used the black filter pre-pump, and a GM/AC Delco filter for post pump up about where the tranny crossmember is. The black filter is something like 40 micron, and the Delco one is 5. I think the number is 25171792 (the older number is 25055052 I believe) it's threaded on both sides and you can get AN fittings for it.

Thanks for the clarification.