Help me find the correct longer wheel studs!

[79cutlass]

Doing the LS1 brake swap on my 79 Cutlass. The factory studs were SAE thread and I need about 1/2" longer with metric thread. I purchased Dorman 610-323 which are M12-1.5x54mm and they have too small of a knurl, fall right in the hub. My lugnuts are M12-1.5 I believe.

[Apogee]

My sources show that the '79 Cutlass came with a 7/16-20 x 1.5" long wheel stud with a .472" knurl in the rear (Dorman #610-186). That said, the replacement stud that you selected should have had a large enough knurl (.504") to require resizing of the holes for a proper interference fit. Since that wasn't the case, it would stand to reason that either your studs are not original or I'm simply wrong.

What studs were you running before and/or what minimum size knurl do you need? Please share the three digit number on the head of the studs if you have it.

There are several OE replacement and aftermarket M12x1.5 options in the length range you specified, but without more info it's a little tough narrow it down, but you can always take a look at them on Dorman's website if you like. Here's a short list of some possible candidates for you: 610-323, 610-365, 610-388, 610-427, 610-443. There are others but shoulder lengths were too long or knurl diameters too small.

If you don't mind running a 2.5" long wheel stud, the ARP #100-7708 has a .508" knurl (maybe too small for you?) and is a much better quality wheel stud than most of the OE replacements you'll find.

Tobin
KORE3