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Discussion Starter #1 (Edited)
Does anyone happen to know what type of fittings are used on the high pressure injection lines. AN maybe? Are they calculated for a certain length? Has anyone made there own lines. Thinking about using Swagelok.
Thanks
 

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length doesn't matter, but wondering why you would do it, seems like a lot of effort when stock are fine.. They need to be metal to hold the high pump to injector pressures..
 

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Much like a header, if the lengths vary, fuel delivery will vary. Some cylinders will starve.
 

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interesting, I didn't know that.. I figured as long as the lines were bled that the actual quantity of fuel in the lines didn't matter, same pressure in would equal same pressure out.. My mistake...
 

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Thats what I figured as well. With longer lines, it requires more pressure to deliver the same amount of fuel. These differences in the length are small. But the pressure fuel is delivered at apparently makes a difference.

I think that may have been the catalyst behind commonrail injection, easier to replace and repair fuel system components.
 

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The line lengh has to be the same,if you have one go bad it has to match the others.

I don't think you could even make a line to hold that kind of pressure and not have a lot of R&D .

Scott
 

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Discussion Starter #8
I don't know what the operating pressures are of the VE pump but the swagelok fittings and tubing, depending on size, are rated over 10000 psi working pressure.
 

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Rise from the grave old thread......

Anyone have an answer for what type of ends are on these lines, or have made thier own?
If I end up making my own lines, I will post up my findings, but would rather find pre made parts than making my own on the fittings.
 

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interesting, I didn't know that.. I figured as long as the lines were bled that the actual quantity of fuel in the lines didn't matter, same pressure in would equal same pressure out.. My mistake...
From the dead I know... but the next time you are over remind me to pull out "Fluid Mechanics", specifically the section on head loss. Its a length chapter so bring a lunch :dustin:
 

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I don't know what the operating pressures are of the VE pump but the swagelok fittings and tubing, depending on size, are rated over 10000 psi working pressure.
Even though they're rated at up to 10000 psi, they wont work as injector lines. The internal diameter is too large, and the wall thickness of compatible tubing is not thick enough to prevent bulging. Compare Swagelok tubing to a factory line, and you'll see what I mean. The excessive ID, and the resulting compression of the diesel fuel in the larger ID line, and the tubing's tendancy to bulge might not even allow the injectors to "pop". Or if they did finally pop, the injection timing, and injection quantity would be way off. They would react like a normal thick wall injection line with a small quantiry of air in the line. Hope this helps.
Bob B.
 

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Custom injection lines.

I forgot to mention, there are shops that will make up custom lines, and they use the same line the factory uses for injection lines. They ususlly want your old line so they can use the same exact OD and ID line, and make the line the exact same length as your old one. Or, they will build you custom lines based on your specs.
Bob B.
 
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