Uhmmm... Maybe a more complete answer would be halpfull here...
The 336 is designated as a "Sport" cam. It has much more overlap than the stock 308 and therefore benefits from and allows higher compression ratios.
It also produces it's (Greater.) power higher in the rev range.
So... You get this kool kinda rumpa-rumpa idle but off-idle performance is pretty flat untill the cam "Comes on" at maybe 3000 rpm. After that the bike takes off and will produce usable power beyond redline. The cam has lots of overlap, so if youre running lots of compression (And you should be with the 336!), the engine "sees" lower compression at low revs. Thats a good thing.
A 1050cc or larger Airhead will really work well with this cam because theyre already producing 'adequate torque' down low and the cam allows the bike to hammer out the horses up top.
A 336 is a great
cam if you install it in a bike intended for cross country trips or high RPM backroad burning . The trade off is that these bikes are not very satisifying to ride around town. Not to me anyway...
Most of the really good running bikes that I remember that ran 336 cams also ran Hi-comp pistons, big intake valves, dual plugs, light flywheels, balanced, and were very carefully set up. Add a big bore kit and some porting and youre in Airhead heaven untill the engine coughs up its guts!
PS: If youre really serious about replacing your cam, MI offers a 324 Sport CAm that I've heard very good things about. It'll support some compression increase but the lower rpm area is fatter. If I drop a dime on a cam, thats the one I'm going for.