They are 11 gauge stainless steel tube (ss) with 1/2" mild steel (ms) flanges. They flow slightly better than the CastFlow and will make more HP.
They can also be ceramic coated to improve performance and reduce under hood temps. Customers have reported picking up 2 1/2 tenths by just bolting these on!!
Newer body style trucks require a coolant line relocation fitting.
ProFlow headers/up pipes can be ceramic coated. This coating will hold up to 1600 degrees prolonged. Pick your color from Black or Titanium. Our ceramic coating is a heat coating only, not a rust preventative.
These are for use on trucks WITHOUT conventional downpipes and have both headers and up pipes almost symetrical. There can not be a downpipe behind the cylinder head. They are custom made to order so expect 1-2 weeks build time.