(I did a search but did not find a description)

Does anyone have a link to a good write-up on a fuel pump relocation?

I have a 73 2.0 that I converted to carbs years ago that I will be converting back to some type of FI.

I found my old three port pump, but also came across a 2 port pump and what I assume is the factory mount (From a 75 or 76 car).
Since I will be pulling the gas tank to replace the lines, I figured it was a god time to do the relocation.

On a side note (Just in case I need to run carbs later), has anyone used the front 40 PSI pump with a 3 PSI regulator at the rear to run carbs?

Yes, this guy:

From reading your posts on other threads, I would not think that you need a step by step tutorial. Just do it. Not rocket surgery

Clay did the high-pressure-to-low-pressure thing on his wife's car. Which caught fire not long after, due in part to the pressure regulator failing and the float bowls overflowing onto the engine. You may recognize this as a symptom of a Very Bad Idea ™. If you're running carbs, use a low-pressure fuel pump.

There are several ways to relocate the pump.

One involves just moving the stock three-port pump to the front, usually near the steering rack. You have to run a new power wire from the factory location to the new pump location, and you need to do a little bit of Adapter Magic ™ to deal with the different hose sizes. Specifically, the larger supply line through the tunnel--you need to go from the ~7mm ID "D" port of the pump to the ~9mm OD of the center tunnel supply line, and from that back down to the 7mm ID line that is plumbed to the engine. You can use brass plumbing supplies, or make up a fitting, or some other method that floats your boat.

Use rubber isolators to mount the pump, like in the factory location. You will either need to weld in some nuts to hold the stock-type mounts, or find a place you can access nuts on the back side of the panel, or fake up some other way to hold it. (E.g., rubber-lined hose clamp to something solid.)


If you go with the late-style two-port pump, some problems are the same. As in, you need to run the power wire to the new pump location, and you need some Adapter Magic ™ to deal with the engine bay end of the supply line. The differences are the exact adapters you need to make up for the pump (the suction port is a different size from all the others) and the exact mounting of the pump on the car. The factory mount is a plate that gets bolted onto a hole in the bulkhead in front of the fuel tank. So you will need to locate where it should go, cut the holes, and deal with the fasteners. (Weld-nuts are probably good, riv-nuts probably will work, sheet metal screws or needing to get a wrench on the nut on the inside of the fuel tank compartment are not recommended.)

So you see that there is no one procedure for moving the pump, because there are a whole bunch of variables in how you can do it, depending on what parts you have and what way you want to do the conversion.

--DD

In general I agree, but, . . .

1) There may be tricks others have learned that I would rather not learn the hard way.\

2) Since I have not even seen the pump mounting of a late (front pump car) I would be guessing at the best way to get close to the factory arraignment.

3) Yes, I can just get ignition power from behind the dash, but was wondering about the best way to get proper switched fuel pump power.

20+ years ago, I would have used a sheet metal screw and a hose clamp and been perfectly happy.

You guys and all your talk about "the right way" to do things is ruining me.

Thanks. I think if I do it, I would be using the new(er) (assuming it is good) two port pump. (which is on the plate already)

So to understand; the pump sits behind the plate in the same section as the gas tank, and the plate location allows you to service it from the trunk side?
If that is the case, that sounds like the best solution.

As for power, I guess I have some wiring to run so it may wait till later in the restoration since I need to get the engine in and running before I start taking the interior out. (Long story and crazy ordered restoration schedule)

Not the best pic. This is looking at the pump assembly from in front of the car.
The pump mounting is on the drivers side in the front firewall that separates the trunk from the tank.

Another ...

That looks great!
Was wondering how to service a fuel filter on a front pump.
Now I am very glad I got the pump with the plate and mount.

Does anyone have a template or measurements from a factory install?
If I am going to cut a hole, I might as well make it look "Factory".

I'll probably do Clip-nuts and have weld-nuts put in when I get the other metal work (rust repair) done.

N_Jay -

I don't understand why folks want to cut holes into their 70-74 914s to do a F
p relocation in the 75-76 placement, when the Porsche Service Bulletin had the relocation on early cars to the lower front firewall up behind the steering rack cover.

It's an easy spot to mount it, easy to inspect & change filters (as well as to inspect your steering rack/boots/etc. at the same time), & any leakage if lines age/crack, connectors get loose, etc. won't pool under the tank.

IIRC the AA FP relocation kit has instructions with it, & that includes the mounting bracket with damper (rubber pad), hoses & clamps.

I had mine done back in 1977 after getting stuck in beautiful Blythe CA in 120 heat with vapor lock, & have been happy with it since for a decade of driving 130K+ miles.

I'd suggest that you follow the factory TSB on this FP relo.

- Not great pix, but you can see mine mounted to the right of the opening in the firewall to the tunnel where the fuel lines daylight below the tank ---v
Click to view attachment Click to view attachment

Good Luck!
Tom
///////

I recall that at least one version of the AA kit gave you a telephone cord and told you to drill holes in the firewalls to thread the wire through and lay it on the passenger floor.

It's not that hard to add wires to the main wiring harness, or at least to lay alongside the main harness.

--DD

Uh Dave.... that was some that was spread around by someone who was an admitted asshole, convicted car thief, and is no longer here. I suspect the was deliberate. I don't ever mention his name. Kinda like BeetleJuice, Say it too many times and he will show back up.

The fire in Betty's car was caused by a cracked plastic line at the firewall. It dumped fuel onto the heat exchangers. This was confirmed by the fire marshall for insurance purposes. It was not caused by trying to use an EFI pump on a carb. I know better than that.

I will look into the AA kit.
On my car the cover plate is something I hate removing since with the 911/930 front suspension, the plate mounts to the bolts through the sway bar brackets and they can be a pain to get lined up.

Does someone have a link to the service bulletin mentioned.
Just because that was the easy way for VW-P to tell their dealers to fix a problem, I am not sure it is superior to the eventual solution engineered for later cars. (Am I correct this was 75 and 76, or did it start earlier?)

I already have the newer pump and plate, so other than a desire not to modify the car (a ship that sailed long ago), is there a good reason NOT To do the later style update?

Were the later style bodies changed in anyway to better accomplish the cutout (Stamped for the hole, etc.) or is the panel exactly the same, just with a cut out?

EDIT:
Looked the AA kit and see they sell the "Guide" separately for $5.50
Not to be cheap, (BS, as I am cheap) but would love to read one before buying the kit.

"I already have the newer pump and plate, so other than a desire not to modify the car (a ship that sailed long ago), is there a good reason NOT To do the later style update?"

If you don't replace the nylon lines inside the tunnel then you will be pressurizing these fuel lines at %100 of the pump output pressure.

Another option is to mount it near the intake air flow above the air delflectors on the rear firewall outside the engine compartment. Another option to consider.

Considering the car is 43 years old, I do intend to replace the fuel line and return line.

My low pressure pump is on the fire wall, and I noticed that one mount on my old pump was rusted to whatever it was attached to. (I need to find my old Haynes and Porsche service manuals to figure out exactly where the original spot was.)

Well, heck! Guess I got fooled on that, too! Sorry for defaming you like that.

--DD

I did the mod this way many years ago after I also got tired of having my pump vapor lock. But I had to hammer the shit out of the steering cover pan to get it back on.
Then it didn't fit quite right, maybe I chose the wrong spot to mount it. But this time I will mount it under the tank, and if I have to remove the tank to service the filter... well so be it.

Both of ours have the fuel pump under the tank. I feel it is a bit safer there than exposed next to the steering rack (even with a cover).

I put a high pressure EFI filter in the engine compartment, and a carburetor fuel filter in front of the pump on the suction side to protect it.