i state a matter of fact as 2 wad a retard is. no reason for u 2
go ballistic dude 
if i run at 10km/h and i turn my body sideways while continuing
to sidestep at 10 km/h, does it mean dat i slowed down? crank also
can slow down, piston also can slow down, heck, everything in the
engine also can slow down. yet, u can tell us cams slow down equals
cam phasing ah? not say i wanna call names lah, but if u cannot
talk sense into someone, den u naturally think dat person is a
mXrXn rite? 
u have no idea wad u are talking about. u mean u can retard HALF
a camshaft ah?
u keep using speed up = advance, slow down = retard. u wanna
speed up the cam until how many times the engine speed? not scared
blow engine ah? u have time and again shown that
u know NOTHING about how cams are advanced or retarded in the
engine.
thats EXACTLY wad i meant when i said 'turn backwards", the
actuactor rotates the camshafts a few degrees backwards while
maintaining the EXACT same speed of rotation as the engine. but dat
does not equate "slowing the cams down". if u slow the cam down, u
have to slow the WHOLE engine down or else risk snapping the timing
chain and blowing an engine. if u gotta slow down the cams in order
to achieve retard, then might as well dun say retard the cam. say
retard the WHOLE engine better.
if u tell me this, then u again show that u do not know the
relationship between overlap and cam phasing. in a SOHC engine,
overlap is fixed by the design of the cam lobes.
be it in a SOHC or a DOHC engine, cam phasing is
about the degrees from neutral position that a cam can rotate. in a
DOHC engine, the individual variations in cam phases WILL affect
overlap but in a SOHC engine as we are discussing, having overlap
does not mean that the engine does not have cam phasing. get it?
now u understand y i say u know NOTHING about engines? u dun
even know the relationship between overlap and cam phasing and
conveniently assume dat a SOHC engine cannot have cam phasing?.
WRONG again. the cranckshaft speed is ENTIRELY dependant on the
camshaft speed. the camshaft dictates when and how fast air starts
to come into the engine, when and how fast the chambers are closed
for compression and combustion and when and how fast the exhaust
ports are opened which in turn decides how fast the crankshaft
turns. if the camshafts screw up the timing, the crankshaft warps.
therefore, a camshaft can NEVER turn faster or slower than the
engine speed (as in YOUR explanantion of cam phasing) but can only
rotate a certain amount of degrees forward (as in advance) and a
certain amount of degrees backwards (as in retard) in order the
effect what is known as cam phasing.
look, i do agree with u dat this debate is going nowhere. until
such time u have brushed up ur knowledge of how an engine works,
there is simply no point in furthering this.
