UNF or UNC

[mattsay]

Hi,

Can anybody tell me if the 5/16 bolts for the inlet manifold are UNC or UNF?

I've seen both mentioned on the Forum.

Cheers.

[DJT]

imported post

UNC (which is usually the case into alluminium alloy). 15 - 20 lb/ft torque.

Dave

[john 4d]

imported post

UNC, tightened to 15-20 lbft.

As a general rule of thumb anything that screws into steel is UNF anything that screws into aluminium is UNC.

John4d

[mattsay]

imported post

Great thanks Guys

[jbuckl]

imported post

john 4d wrote:

UNC, tightened to 15-20 lbft.

As a general rule of thumb anything that screws into steel is UNF anything that screws into aluminium is UNC.

John4d

Should be, but the stag exception is thattrailing arms have unf studs into aluminium oops:?

[jleyton]

imported post

i m inlet manifold on Weds and even 20lb ft feels teeth grittingly worying ino alloy.

Fortunately, I'd helicoiled them all but it still felt pretty tight to me :shock: