On a 1972 Olds 442 with factory front disc brakes. Which rotor kit out there is a direct replacement for the OEM?

Current rotors are showing groves and not sure about turning them as that can cost more than just getting a new set of rotors.

I have 15" rims with 4.50 backspacing

 

What do you mean by "rotor kit"? Are you talking about rotors and pads for one price? The only ones I see are Centric/Power Stop.

I just use Raybestos or Wagner rotors, though even those brands are Chinesium these days. Tuning the OEM rotors is the only way to get "OEM" quality. As for pads, I just go with D52 semi-metallic. Bosch, Bendix, Raybestos, Wagner are all about the same. Get the caliper hardware kit (pins, bushings, and o-rings) also.

 

Just hit up RockAuto for options on rotors. Whatever you purchase, be certain to check runout!! I went through an experimentation phase year before last and bought 4 sets of rotors. 2 had runout >10thou, 1 was wildly unbalanced (clearly had severe core shift). The Centric Premium slotted ended up being in the best shape. So if you want to experiment with cheap rotors then be sure to get them from a local store so it's easy to return.

Near as I can tell there are two foundries making rotors - there are 2 slightly different castings. From there the difference is all in the machining and coating. I try to find a company that clearly states they do the final machining in the US as the QC is somewhat likely to be better.

there's a very broad selection of pads available for our cars. That really comes down to personal prefference.

Note that all the brake stuff is identical to the Chevelle, so you may find options easier using that as a search.

 

JC Whitney is another great brake parts / kit sets source - always look for their discount codes either on the site or sometimes posted online for extra savings. Free shipping on most purchases also a plus.

 

Anyone ever get this direct bolt-on replacements for the factory front rotors?

They are cross-drilled and slotted with carbon fiber/ceramic pads. $100 per side.

https://www.summitracing.com/parts/p.../model/cutlass

Reviews are good and people claim their classic car stops better than the factory rotors.

 

drilled rotors seem to have a mixed rep for street use -check other sites for stories of them fracturing due to the repeated heat cycling of street use.

I think your choice of calipers should be priority - maybe look into the Wilwood dual caliper units to couple with high quality pads and solid rotors - I went that route on my '72 ragtop and have no complaints thus far

 

Drilled holes in rotors can crack. Don't always, but it sucks when they do.
Rotors aren't going to have that huge of an effect on the performance. The slots and holes, at the end of the day, are mostly for looks. Just pick whatever you can get and return easily because you need to do you own quality control! Check runout, check balance, and overall quality of the casting and assembly.
Pads are where you can make the difference. There's a lot of options for the stock brake setup, so just go digging and pick whatever meets your fancy. Or, do one of the various aftermarket bolt-on caliper upgrades.