fuel line size
#1
fuel line size
I have built a 468 cubic inch motor and wondering what size fuel line I need. The boat had 3/8" fuel is this sufficient for a 500-550hp motor or do I need a 1/2" line? The motor will be dyno'd on 1/17 so I will know exact hp then. The fuel is only about 3' from the pump and then 2' from the pump to the carb. I am running a holley 110 gph electronic marine fuel pump.
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Thunder, those anti-siph valves have a ball right in the middle of the orifice that is spring loaded. It would be interesting to see the flow rate of them, but I can't believe they flow as much as a 3/8 fuel line. 3/8 should be fine, but check the fuel seperator, because a lot of the stock ones only have 1/4" fittings and they are 90's also.
#7
I haven't bought any fittings yet as I wanted to make sure I got the right sizes. I am redoing the entire bilge area along with the motor so everything will be new when installed. I will also have a dash mounted fuel pressure guage and I might put a mechanical gauge in the line for a back up. Thanks for the replies.
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the valves are so restrictive I can't see how stock engines get enough fuel thru them..have had many issues with them..they are required by C/G but have had to remove many to cure starvation issues, they are in the fitting right on the tank where the line attaches at the tank...Rob
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the valves are so restrictive I can't see how stock engines get enough fuel thru them..have had many issues with them..they are required by C/G but have had to remove many to cure starvation issues, they are in the fitting right on the tank where the line attaches at the tank...Rob
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As a general rule this is what the recommended fuel line size
0-250 hp #4 or 5/16 id
250-375 #6 or 3/8 id
375-550 #8 or 1/2 id
550-800 #10 or 5/8 id
800-1200 #12 or 3/4 id
Pressure is as important as volume.
and yes smaller will work, but it might not...............do you feel lucky today?
0-250 hp #4 or 5/16 id
250-375 #6 or 3/8 id
375-550 #8 or 1/2 id
550-800 #10 or 5/8 id
800-1200 #12 or 3/4 id
Pressure is as important as volume.
and yes smaller will work, but it might not...............do you feel lucky today?