ID help - brake rotors

These are 5x4.75 bolt pattern rotors on my truck project. The front stub is from a b body. Not sure what year and I want to order replacements.

they look like the standard 11" front brake rotor from any Impala or Caprice 77-90 with standard brakes (NOT wagon or 9C1). If you want to be sure, take one rotor off and lay a ruler across it. It should measure 11 inches in diameter, give or take a little bit. If it does, I'd just pick up a set of regular rotors for a caprice or impala.

If you measure it and it's around 12 inches, then it gets more complicated since you said it's a 5 x 4.75" bolt pattern

Thanks. They are 11" up front. I assume those were matched with the 9" drums? I have stubs from a b body. Not sure if he went with bigger drums out back, but I think it'a a 7.5 10 bolt which seems like a base setup to me.

Yes, the stock 11" front brakes had 9" drums in the rear.

If Your in need of replacing brake lines that are custom made, try this company.

https://www.inlinetube.com/

I used them for my rearend change over.  They have custom to original for disc or drum.

I choose the Stainless steel lines for my 1979 Caprice.

I have purchased parts from them before. Does anyone make a bolt on rear disc brake kit for the 9.5 inch drum setup?

I think Stainless Steel Brakes Company does. And I think Jegs and Summit Racing both have an 'in house' kit that uses an old cadillac caliper.

When I did a rear disc conversion, I used the rear brakes off a 1998-2003 Camaro/Firebird. It's a 12 inch rotor and doesn't clear a stock 15 inch steel wheel, but it's almost a direct bolt on.

Here's a link to a Hot Rod article about the rear disc conversion:

https://www.hotrod.com/articles/ccrp-1204-budget-gm-rear-disc-brakes-swap-junkyard-builder/

Thanks. Good article.