1/2 inch cp3 fuel fitting - Diesel Bombers

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1/2 inch cp3 fuel fitting


Old 08-08-2012, 07:34 AM
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Default 1/2 inch cp3 fuel fitting

So while i had my engine out i decided to do some improvements on the cp3 on my engine.
One of the things i did was make a 1/2 fuel fitting for the supply for the cp3.
Most of the 1/2 fuel fittings you see out there are still too restrictive because it bottlenecks down to a smaller fitting when it reaches the part that threads into the pump.

The stock 3/8 fitting Has an inner diameter of .232" with equates to about .0422 square inches.

The modified fitting i made was pieced together with a half inch ac line fitting and a M12x1.5 to jic. i cut the jic part off and welded the ac fitting on to it and that took care of the 1/2 inch hose part.

The M12x1.5 fitting on the other side still had to be taken care of so i bored out the fitting from .232" to .295". i could of probably squeezed out more of it, but i was pushing it already.

The area had increased to .683 inches squared resulting in about a 62% increase of flow capability.

Here are some pictures of the fitting.

Side by side difference:

Size difference between both fittings on the side that goes into the cp3:

the 1/2 inch fuel line attached:

Clearance with a modded wire harness:

Link to discussion thread:

Attached Thumbnails 1/2 inch cp3 fuel fitting-20120802_185238.jpg   1/2 inch cp3 fuel fitting-20120802_185116.jpg   1/2 inch cp3 fuel fitting-20120802_232803.jpg   1/2 inch cp3 fuel fitting-20120802_205730.jpg  

Last edited by 2500HeavyDuty; 08-08-2012 at 07:37 AM.
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