Learn me- lug stud Mumbai jumbo.

Swapping the 8.8 into my Celica. I need to redrill the axles for 4x114.3 and that means reusing the Toyota lug studs for the rims that are already on the car. I know the ford exploder studs are way different. My question is when the Celica studs say "m12-1.5 serrated wheel stud 14.22mm knurl 37mm length" the m12 is the bolt size right? And does that reference to the size of the bolt where the threads are? Or does it refer to the head size? Or does it refer to the thickness of the bolt at the spot just under the head, where the bolt actually seats into the axle??? Basically I need to know how big of a hole my machinists needs to redrill on the axles, so I can transfer my toyota lug studs over.

Side note- the exploder studs are "1/2-20" does that mean 1/2"??? If so, that could mean the 12mm is nearly the same size.

m12-1.5 is 12mm thread with a 1.5 mm per turn of the lug nut called pitch. the 14.22mm knurl means you likely need a 14mm hole as you want the knurl to bite in.

Ah! Thanks so much man! So telling the machinists 14mm will work? Or is that just an educated guess?

I can tell you this an ARP 1/2"x20x3" with a .625" knurl wheel stud will require a hole drilled into a rotor by a 39/64" drill bit.

You'll want at least a 0.025-0.035" press fit minimum.

Normal they put the hole size in the spec but not always if it were me I'd likely drill a 13.5 hole and see how the 1st one presses in.