Im talking about rust on the outside, it just looks ugly and shit.

Andy your so finnicky

I hate rust, I am trying to only use aluminum for nearly everything.:)

lol...I guess I just gotta figure it out when I get there...b/c I can't have rust in my engine bay...ew ;)

I hate it too so I painted the pipes that looked a little rusty, and left the lowere pipes alone :/ didnt feel like taking everything apart again for vanity.

Im thinking about stepping down in size, when I do, Im going AL. easier for me to work with.

so....I think I read in the thread...going from 2.5 to 2.0...on both or just turbo side?

I would just use 2" pre IC, and 2.5" post
-Michael-

just curious... why?

I know the TB is 2.5 but does the size change after the IC slow down the intake charge velocity?

Just choose the sizes that let you use the fewest transitions. My intercooler has 2" inlet/outlet, as does the turbo...so I'm going to use 2" pipes with a transition before the TB.

pipe size thread :P
https://www.miataturbo.net/forums/sh...ed=1#post76235

I said to use the 2" then 2.5" to keep the velocity up going into the cooler a bit and then use the 2.5" as it comes out so there are no transitions.
-Michael-

why not just go stainless steal , It makes for better intercooler piping than mild, try to find a industrial supply their prices arent bad.