1968 camshaft

Hi All.
What are the differences, if they exsist, between early commando and later cam?.
I meant the other difference over tacho drive between 20M3 and 20M3S.
Had the 20M3 and 20M3s cams the same height lift?.
How i recognize if the cam is for Atlas or for a 20M3 early Commando?

Thank you.
Piero

Standard is,
Dominator cam 292° duration 0.306' lift.
Commando cam 316° duration. 0.326' lift

Thats info from newman cams on what's available today for points behind the barrel.

However my reading. Says that dominator/atlas/commando cams standard are all the 650ss grind not to be confused with 2s cam made for the combat motor.

The same performance cam will act softer in a bigger cc motor.
What's a race cam in a 650 becomes a midrange cam for an 850.

Early domi QR cam if interested: http://atlanticgreen.com/images/cam140.gif

SS is SS twin chain
1S is single chain "lobe profile" identical as above SS
2S is combat only single chain

SS cam for twin chain NHT engines: 650SS 88SS 99SS atlas thru 20M3 commando



NHT single chain cam named "1S" : 06-1084 20M3s through MKIII 850 except for oil scrolling on last 06-2608 late 74&75... Lobes identical to all previous

If you want a view of a few NHT cam profiles:
http://atlanticgreen.com/camsurvey.htm
Norton Camshaft Profile Survey
David Comeau May 2001-Update 3S cam/HC168 February 2019