If you are going to look for improvements with a cam change I suggest you change the heads at the same time. Yes it will be more money but better in the long run.
I tried this with my 73 L-48 and the stronger valve springs that were needed caused the rocker arm suds to pull out of the heads. The studs are just pressed-in instead of threaded in.
My plan was to change the heads out later and it almost worked until a summer of driving caused the failure. Fortunately I was close to home and not on a road trip when it happened.
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Brian - NCM Lifetime Member
73 coupe L48, Flat-top pistons, Performer RPM Heads, Crane Cam and roller rockers, Holley 650 vac sec. Performer intake,
3.55 gear BTO 200-4R trans,
Leather seats, Seatbelt Plus 3point seatbelts, Pioneer CD player
Magnaflow Exhuast System
Dewitt radiator and dual electric fans
Borgeson Steering box