When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Raised white letter tires for 1970-72 were either Goodyear or Firestone. In addition to these, US Royal was added for 1972. The Goodyear tire had white letters reading Goodyear Wide Tread F70-15. Firestones read Firestone Wide O Oval. US Royal read Uniroyal Tiger Paw. Only a few examples of the US Royal whitelettered tire were seen on 1972 cars, and their authenticity remains unverified.
I would go as far to say that any of the three brands that Paul mentioned would work for 1968-1972... Obviously, Goodyear and Firestone were the main players during those years, but I have seen original U.S. Royal (Uniroyal) blackwalls on a 1969 and original U.S. Royal whitewalls on a 1971. I've also seen a 1972 with U.S. Royal white letters, but like Paul, tough to say whether it was real or owner inspired. It WAS a cool look though!
Having said that, your 1971 could have been equipped with blackwalls, whitewalls, or white letter tires in 1972. The build order or window sticker would call out they tire type, but not the manufacturer. Tires were installed on an availability basis and since there was no way to tell what was going to be in inventory, you won't know the original brand unless you are lucky enough to have the original spare. All tires on a given car WOULD be of the same manufacturer (for warranty purposes).
The white letter tires as described were the most popular tire by far, althought they were a extra cost option. 1972 Corvettes came standard with F70 15 blackwall tires. Whitewall tires were also available at extra cost.
Here is a link to the 1972 Corvette specifications. It has all the information you would be interested in. pages (gmheritagecenter.com)