I'm using them for an EFI setup that's been on the road for a little over 6 months (and now garaged for winter); easy to assemble; can't speak to longevity or potential for work hardening.
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Mike - '68 Camaro with some stuff done to it
I have used the aluminum line and crimp connectors for 3 years now with no issues
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Rod Prouty
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I used Russell tubing and fittings. I put a short stretch of flex hose between the engine and the tubing parallel to the crankshaft just to allow for some movement.
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Mike - '68 Camaro with some stuff done to it
Yep, no problem. Russell is good, also have used Fragola. Even the Summit brand isn't all that bad. Just have to make sure the aluminum is nice and straight, no large flat spots from the roller used to straighten the tubing, etc.
Just like Mike above me said, you'll always need a piece of flexible hose somewhere.