75 Corvette Fuel lines

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Jul 27, 2021 | 05:33 PM

rodney25

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75 Corvette Fuel lines

Hi All,

I have a 1975 Corvette with BluePrint 350. Ordered a new fuel pump with higher PSI & GPH than stock. My original fuel pump is a 3 port but the new fuel pump is a 2 port.
My question is can I convert the fuel line to 2 port? Or must it stay as 3 port. I know one line is fuel from the tank and the other line goes to the carburetor, but what is the 3rd line for and can you get ride of it?

Thanks

Jul 27, 2021 | 06:39 PM

69L88

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From: Apple Valley, MN

The third “port” is for a return line back to the tank. You need to keep that return line because it is key to keeping your under hood fuel cool, avoiding vapor lock.

Jul 27, 2021 | 07:04 PM

rodney25

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Can I use the Holley 2 port fuel pump and use a none orafist vapor filter separators (ACDelco 25055048 - Professional Fuel Filter) for the 3rd line to support vapor lock?
Found this link on YouTube

Jul 29, 2021 | 06:24 AM

7T1vette

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From: Crossville TN

Doubtful, with today's ethanol-laced fuel...

Jul 29, 2021 | 06:57 AM

4-vettes

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Bloody hell Mate. just do it right. why try cutting corners. Just do it right the first time.

Jul 29, 2021 | 12:44 PM

kodpkd

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From: Loveland

I installed the AC fuel filter with return line and solved my hot start issue.

Jul 29, 2021 | 02:34 PM

OldCarBum

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From: Napa Valley California

You should put a fuel pressure regulator and gauge in the system as well.
If your fuel pump doesn't have the return line port, just make sure the regulator does.

Jul 29, 2021 | 02:55 PM

Jebbysan

Dr. Detroit

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From: New Braunfels Texas

Return the pump and buy the stock replacement......you do not have enough power to worry about it. The highest rating of the Blueprint 350's is 385 and a stock pump will run that just fine and be happy with the stock return line setup.

Jebby