273, could it be a commando and CAM question?

Thanks for all the replies and information, greatly appreciated! I'll try the compression test, have a peak inside the plug hole and feel with a straw to see if I have those Commando pistons :)

I'm still curios about the cam though, previous owner staded 340 cam from Sealed Power, so It's a reproduction If he's right. I found this on the forum "268/272 and .444" on both intake and exhaust is the Reproduction spec" for a 340 cam.

A friend have one of those sb whiplash cams from hughes on the shelf, he also have a Comp cam Xtreme Hi-lift XE275HL.
Links:
http://www.hughesengines.com/Index/...V2hpcGxhc2ggTXVzY2xlIENhciBDYW1z&partid=25114

http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=631&sb=1

Are these way to big for my combo? Just curios since we share garage and they are availible!