You certainly got a deal on that head but........
There is really very little use for R sport heads these days, unless you really get a deal. Most of them have been milled for too high CR for the street.
These heads were designed well over 30 years ago and a lot of knowledge on head design and porting as been gained since then. I doubt that the R sport heads were even designed and tested with a flow bench. Put one on a flow bench and you will know why I say this.
Basically the ports are large but not well shaped. Some will flow a good deal of air because of their size, but that size tends to slow down the flow. This may work for high rpm HP but does not for faster acceleration through a wide rpm range. The deal of large port vs small ports gets complicated, because you can have small ports that actually flow more on a flow bench, will support faster acceleration in the real world in mid rpm ranges, but will give you less high rpm power because of there smaller volume. In an actual race situation which way to go often depends on what the track is like and who you are racing.
The R sport valves are large but tend to be shrouded. I've got a couple of R sport heads that I got to analyze or use, and ended up not using any ---- yet.

John
v-performance.com