I have to change cam on my sbc 350 290 hp .Is it worth spending extra money for roller and what are the benefits.
Anyone have any ideas about this. IHAVE A 21' RUNABOUT with a 280 volvo stern drive.

no! with the 280 drive you will see vary little gains in mph..but a hotter flat tappet cam would be better..i suggest a comp cams xtreme marine cam,i would not go any bigger then the first cam on the list or you will be changing your exhaust..

http://www.flatlanderracing.com/compcams-sbc01f.html

If you only want 290HP out of a 350 it is not worth it. A more aggressive cam will give you more gain. However, if you have a standard exhaust, too much overlap may make the engine ingest water at low RPM or when you stop.

Hate to say it being I'm always for any upgrade but unless you plan on doing everything else save your money.