.480/230 cam in an 8.5 CR 360?
From the Comp Cams valve timing tutorial you can figure out your timing events after you study it a bit. It helped me. You can take the duration (total) and the installed angle to get the ABDC closing. It will be the installed angle plus one-half the duration minus 180. For example with my cam; (108+(280/2))-180=68ABDC. If you advance the cam, the closing point comes quicker on the compression stroke and thus increases the dynamic compression. At the same time it opens the intake sooner (while the engine is still on the exhaust stroke and beginning the overlap period) causing more reversion of exhaust into the intake at low rpm but better cylinder filling at higher rpm.