350 vs 350R

I am working on machining a 1972 olds 350. I went online to find some rebuild kits, and as much info as i could. Then i came across a kit for a 350R. I was wondering if someone could tell me the difference between these two engines or at least a place to find some info on them. Thanks

do you know what body it came from? Also do you have the ability to check the vin? If you can get the car model and the 5th digit off the vin, it will be easier to locate. Also there should be a letter code on the block itself that will help identify the engine. It should be stamped somethere on the top half of the block near one of the deck lids. Is the engine a gold color? 350r could be one of two things, 350 Vin-R or 350 rocket. In 72' they didn't use the 350 vin-R so the option is probably the Rocket. The rocket motor was a high performance model so the heads and such will be different. Make sure you specify it's an Olds motor and not just a GM motor. They all have the same displacement but everything else is different. If the motor was gold in color, chances are it was the rocket.