I need help - can someone tell me what size thread (what adapter) I need to connect heater hose to the hole in lower intake on 351W engine? I live in Russia and I'm not very good at AN or standard threads....
in the picture it's right below blue fuel rail adapter...
I'ts either a 3/8" npt or 1/2" npt. Older Mustangs used 3/8 npt heater hose fittings but most newer intakes are tapped for 1/2". Almost all heater hose fittings in the after market are 1/2" npt. If it is bigger than the temp sender then it is 1/2" npt.
Aftermarket intakes usually use a larger hole than the factory ones. National Parts Depot makes a factory style fitting to fit the larger aftermarket hole.