273, could it be a commando and CAM question?

I don't know your mechanical proficiency so please don't be offended, but here goes;

Cam brand and/or fancy model name/number in a buddie's car don't mean squat, and without documentation to back it up, neither does the previous owner's recollections of what he did, back when.

If you really want to know what size cam is in YOUR motor, it's time to get a degree wheel mounted up and check the REAL cam specs. Use a piston stop (an old hollowed out spark plug with a bolt/nut ran through it works fine, just be sure you smooth the end touching the piston to prevent damage) and rig up a firmly mounted pointer to zero it in. Once you come up to speed learning how to use the degree wheel, you'll be able to determine the duration, overlap, lobe lift, centerlines, and if the cam is installed advanced, retarded, or straight up. It's the only way you're going to know for sure. Even taking the cam out and looking at the ID markings (if there are any) won't tell you as much.

Ditto on the compression check. Get a tester that screws into the spark plug hole, block the throttle and heat riser butterfly (if it's got one) wide open, remove ALL the spark plugs, and spin the motor over. Let the motor hit on compression about four to five times to get an accurate read, just be sure to use the same exact number of compression hits on each cylinder (the engine will buck every time the cylinder you're checking comes up on compression). Be sure to use a freshly charged battery for consistency.

Getting a good read on the cam specs and accurately measuring the actual compression in the cylinders will go a long way to letting you know what's really going on in your engine.