This is the first time I was shown the specs for your reground cam and I
agree with Jarrid...it looked at first, like you reversed the data between
the stock and hotted cam. After checking stock grind I see you did not err
in this reporting but your data is really a shock.
Did this shop really know what a stock Alipine V was using as a stock
grind?? Did they discuss their grind with you first??
Below I list what we are dealing with;
series V
stock your regrind 1968 fast street/rally cam
Intake/ open 29 btdc 17 35
In/Close 63 abdc 53 65
Ex/open 69 bbdc 60 65
Ex/close 23 atdc 14 35
lobe lift .300" .225" .435" (full race lift= .480")
While at first glance this looks like the shop has sold you a grind that
will make less power than the stock grind, I (we) may be wrong.
The data shown by Rootes and other mfr's back in those days was for
measuring valve lift and degrees with the valve lash set as specified and a
dial indicator was expected to be used to determing the crank position when
the valve actually commenced to just start to move. This is very
inaccurate for several reasons, but it is what was done back then.
Nowadays, the cam specs are given with valve at specified clearence and
then lifted .050" off it's seat (or that distance from being seated).
In this manner, all backlash and other error causing clearences are taken
out and several cam grinds can be accurately compared.
Under the circumstance we find ourselves with in your cam, (old data system
and new data system) we cannot truly compare the actual crank degree for
each data given. Perhaps when the stock cam is moved to where the valve
is lifted .050" the actual timing degrees may be milder than the regrind
(but I feel in my gut that something is wrong).
The stock SV cam has a lift of .300" per Jarrid. I have no confirmation
here but assume he knows this pretty well).
Your new grind is quoting a lift of .225" or .255" (whats the correct
data?). Either of your figures is BADDDDD. Not enough lift !!!
Possibly you need to put a dial indicator (or use a good vernier caliper)
on the push rod end of the rocker arm. Turn the engine slowly and measure
actual lift there. Don't measure at the valve end as there may be a ratio
in the rocker arms which multiplys the movement (I forget if this is true
or not).
That small lift of yours (if true) will kill power for certain.
If that timing data is true or close to true, you have a bread wagon truck
engine instead of a torker sports car engine. Let me have the story or
corrections to the data the grinder has provided.
Lets hope he gave you a nice hotted up grind and somehow gave the wrong
spec sheet with it?????????? Also...what the hell is your spec "l/C 108"
mean. I have tried to figure it out and must be missing the l/C meaning as
well as the 108 number.
Dick T.
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