Is 1/4 inch outside diameter copper tubing big enough to run as a wastegate line or should I use 3/8 inch outside diameter?

Thanks,
Brian

 

TiAL recommends 6mm ID, so the 1/4" should be enough as long as the wall isn't too thick. How do you attach copper tubing to the fittings at either end?

 

I was just doing it with some short bits of silicone hose as a joint... kinda like how you put an intercooler together with intercooler pipes and silicone couplers.

Brian

 

why not flare it or at least use compression fittings?

 

I was thinking of using comp fittings, but they make it even a little smaller because of the little insert thing... and I don't have a flaring tool so...

Brian

 

With a compression fitting it grabs the outside not the inside so the ID is still the same.
The whole reason to go with a metal tube is not allow it to melt or pop off. You decided on going with the metal tube might as well take the extra step in reliability and get the compression fittings.

 

Don't compression fittings have a little trumpet-shaped inner tube that goes up into the end of your pipe?

Brian

 

They have them that grab the outside of the tube and seal that way. Just used that style the other day making some tubing at work. You can probably find them at mcmaster.com for dirt cheep.