I have run many , many sets of rollers over the years. Couple key points- If you are happy with your cam, then stay with the same ratio. If you go to 1.6 rockers it will be like going to a more radical cam. Your idle is is going to get ruffer and it may cause you problems. So don't do it unless you want that affect.
Don't even think about switching to 7/16th's studs. This isn't necessary until you start running BIG lift cams or a roller cam. It's the kind of stuff you see at the drag strip idling at 1500 rpms. Its not a "just drill and tap" switch. If you need 7/16 studs in a head then you are at the level that you should run stud girdles. And in order to run girdles you will have to pull your heads and send them to the machine shop to have the holes drilled by an alignment fixture (makes all holes perfect in line for the girdles). Of course girdles mean you need polylocks and that means tall valve covers to clear all that BS.
Stay mild and you don't have to deal with that crap.
There is a performance difference and several benefits to roller rockers. The biggest difference is they will eliminate much of the valve guide wear associated with the side force caused by stamped rockers. (as they slide on a layer of oil back and forth across the tip of the valve). Since there was friction where the stamped rocker rotated on the nut you will also gain that as power. They are quieter. I got caught a couple years ago running them in a stock car class where they were not allowed. I pulled them and came back the next weekend. I am telling you from first hand experience. I COULD TELL A DIFFERENCE! It wasn't alot but I could tell my motor was not pulling as hard as it passed 6500 heading toward 8000 at the end of the straight away. Now you might say "what's that got to do with my stovebolt?". It doesn't, but if I could feel it, then on a dyno it would be measurable even at 3000 in your stovebolt.
In other words they will eventually pay for themselves at the gas pump.
JMO
SuperDuke "strongly recommends roller rockers"
