I have a set of four 1/4" spacers that I'm planning on using to get my stock 16" wheels to sit a little more flush to the body on my '92 Z28; just a cosmetic thing for me as I like flush fitting wheels.

My question is, is it necessary to get longer studs if I'm adding spacers? I may do just 1/4" or stack two of them for 1/2" total. If I do decide to do more than 1/4" I have longer studs on the way that I'll just swap in, but would it weaken the studs or lug nuts if I'm only using a single 1/4" spacer?

Drum brakes in the rear if that makes any difference.

With 1/4" spacers you should be OK, but I recommend at least 5 full turns of nut on the stud. (officially the diameter of the stud should be the minimum engagement depth)

As for stacking spacers, this is never good. if you need 1/2" buy 1/2"

Also the cheap aluminum windowed spacers are somewhat fragile. They have been known to break at times so use at your own risk.

Thanks for the info.

What spacers should I look into getting?

May or may not be relevant, but my car isn't a daily driver and isn't abused on the roads

Look for something machined from billet stock instead of cast.