[moto-d]

Hello --- restoring my 67 GTO to as close to factory as possible.

It's a May-built 4-speed car, without A/C.

Would it have had a factory fuel return line because of its late build? Or was that strictly for A/C cars no matter when they were built during the production run? Appreciate the help. Thanks!

[helmerrock]

To my knowledge all 67 GTO's had the return line. I had a Dec built non A/C that had the return line from the fuel filter and a later build that the return line came off the fuel pump.

[moto-d]

I'm under the impression some did and some didn't ... just don't know the deciding factor, whether it was based on when the car was built, or whether it had A/C, auto tranny or some other variation. Reason I ask: tried to get a replacement 5/16" fuel sending unit to match the 5/16" fuel line, but they don't make one with a return line.

[helmerrock]

Both of my 67's were std trans without A/C. For sending unit with return line I ended up buying one with 3/8 feed and 1/4 return.

[moto-d]

Did you run a single line from the pump to the carb then, or go to the two line system with the fuel filter up by the carb?

Also, did you switch to 3/8 main fuel line to match the feed? I've already got 5/16 and that **** costs a fortune to ship.

[helmerrock]

I bought the 3/8 front to back line on the 67 I have now. I got the pump with the return line fttting from the pump. The pump is designed for 5/16 input but the 3/8 hose clamps on fine with no issues. I used the steel line from the pump to carb that allowed the use of an in-line filter. Looks stock but I think if the return was on the pump the steel line to carb had no filter (just the quadrajet inlet filter). Since you already have the 5/16 line from the tank I would go ahead and use it. You should be fine to connect the 3/8 sending unit to a 5/16 line without a problem. By all means you should use a return line, especially with todays available gas that practically boils at room temperature!

[moto-d]

OK, that gives me some stuff to think about, thank you very much.

Yes, I think I'll use the 5/16" main line.. I've actually got two sending units .... one with a single 5/16 feed and the filter "sock" on it, the other with 3/8 fuel and 1/4 return feed, and no sock.

I'm assuming it doesn't have the sock because a filter would be required up by the carb?

[helmerrock]

Fuel sender unit should have a sock regardless. You can buy the sock.

[moto-d]

I see. Do I need the special filter line, filter and filter bracket then? Sorry for all the questions, but this whole gas line thing is confusing to me LOL.

[helmerrock]

Option 1: Buy correct fuel line set (3 pc). That has the carb to filter line, filter return to return line at frame, and pump to filter. Use GF-98 filter. Use pump without fuel return fitting. Not sure if all cars used filter bracket but not absolutely necessary(Correct for early builds)

Option 2: Buy correct pump to carb steel line. Use pump that has return fitting. Connect that to return line. Use no filter except the Q-jet inlet filter. No bracket (Correct for later builds)

Option 3: Use pump with return fitting, GF-61 filter, and use the carb to filter line and the pump to filter line as in option 1. Bracket optional. (Not technically correct but looks stock and works correctly)

I used option 3 because I had all the pcs to do it without buying more parts.

[moto-d]

Cool, very helpful ... Option 2 seems right .... I have the correct single-piece pump to carb line. I have the pump with the return fitting. I have the 1/4" return line. I'll get the Q-Jet inlet filter.

The only thing that may be a bit weird is the 3/8 sending unit mated to the 5/16 tank-to-pump line, but as you stated, that's likely not a big thing.

I'm in your debt.

[geeteeohguy]

My December 1966 built '67 has no AC but does have the HD cooling system and vapor return line from the large fuel filter mounted at the T-stat housing in a bracket. And it keeps the fuel nice and cool. I ran without it for a number of years and had vapor lock issues. Not anymore! There are pictures of this on older threads about this topic....I'd post a fresh picture, but can no longer post pictures on this forum.

[moto-d]

I've got the same set-up on my late '67 A/C GTO ... I think for this one, I'll run just the carb filter and solid fuel and return lines.

[fyrffytr1]

Are you trying to run the tank to pump line with the body on the frame?

[moto-d]

Nope, the body is off the frame currently. Makes life easy.

[moto-d]

As long as we're at this point, it's time for all new lines.