Aeroquip preformance hose runs small. 1/2 inch hose is actually .41 on the inside. I am rerouting oil lines to make way for the intercooler piping. 1/2 JK is the largest available for teh 16 18 mm threads used by mazda i am stealing oil for theturbo at the fitting where the oil leaves the front cover.

Are the .41 I.D. lines large enough or do i need to get bigger hose.

 

Huh?

Are you talking about the oil cooler lines? If so, then use -10 stuff.