12/74 280z Fuel Tank

[NC280z]

Greetings everyone!

 

I've discovered (rather embarrassingly) that the fuel tank in my '75 280z (production date 12/74, 213th produced based on VIN) actually belongs to a 260z! I found this out after troubleshooting a fuel issue related to a rusted pickup tube that's been introducing air into the fuel line. There are NO 75-76 tanks in usable condition available anywhere that I can see and reconditioning this tank is likely not an option, so my question is this: can I replace my tank with a new, baffled 260z tank? I know that the primary difference from 260z tanks to 280z tanks are baffling and pickup tube diameter (5/16 vs 7/16). The fuel pump I'm using is a NOS unit (7/16 inlet), and the car seemed to run fine until the pickup tube pinholes became large enough to suck in air. S30World is working on a new production tank for 75-76's, but those won't be available until late this year and the new 260z tank I've sourced is available now and could be in-hand in two weeks. The engine in my Z is a warmed-over N42/N42 flattop with stock F/I system, so I don't think it'll need crazy amounts of fuel. I suppose my main concern is any issues that could come about from a 5/16 outlet on the tank going to a 7/16 inlet on the fuel pump. 

[datzenmike]

If you are using a 260 tank now with the smaller 5/16" tube and it's working, then replacing it with another 260 tank shouldn't be a problem as nothing changes.

 

That would be car number 200213? Out of 70,000 built that year.

[NC280z]

That's correct, 200213's the VIN, and thanks for the quick reply! I've got a glass fuel filter inline between the tank outlet and pump inlet (low pressure) and noticed a good amount of bubbles in the filter while the car is running. Filling the tank a bit higher reduces the bubbling significantly, which I assume is due to a pinholed pickup tube pulling in air. I was concerned that the diameter difference between the pump and tank might cause cavitation or other issues. 

[Crashtd420]

7 hours ago, NC280z said:

That's correct, 200213's the VIN, and thanks for the quick reply! I've got a glass fuel filter inline between the tank outlet and pump inlet (low pressure) and noticed a good amount of bubbles in the filter while the car is running. Filling the tank a bit higher reduces the bubbling significantly, which I assume is due to a pinholed pickup tube pulling in air. I was concerned that the diameter difference between the pump and tank might cause cavitation or other issues. 

If your tank is good shape and it's only the pickup tube a cheap option is you can drill out and remove the old pickup and weld on an npt bung in its place.... then purchase a marine gas tank pickup tube.... cut to length needed and thread it in... then you can put whatever size nipple you need for the fuel line size you're running...

Not necessarily the one you need but an example 

[NC280z]

So I'm getting mixed opinions on air/bubbles in the pre-pump filter. Does anyone else have a clear filter  before their fuel pump, and if so, do you have any bubbling? I've always thought that any bubbling in the line was indicative of air in the system, and needed to be resolved.