Modifing S4 Fuel Rails

[RETed]

S4 fuel rails should be all metric threaded.
At least US-spec ones are...
I dunno where you got your secondary fuel rail from, but all US-spec S4 turbo fuel rails have the PD on the primary fuel rail.
The PD end should be 12mm x 1.25.
The other 3 ends should be all 14mm x 1.5.

Aeromotive just came out with an adapter that goes from 5/16" hose end to -6AN male.
This makes it a lot simpler to mate our stock fuel lines to any AN set-up.


-Ted