318 cam timing dilemma?

[Bill the arcstarter]

Guys,
I was hoping someone could give me some advice regarding degreeing in a cam 
in my 318 (Dodge pickup)...

The problem started about three years ago when I was young and stupid I more 
or less just slapped in some sort of "tow truck cam" with a stock 
emissions-type timing chainset.  I never did get much of a performance boost 
out of it...  Not being wise in the ways of the masters - neither did I 
acquire nor retain the datasheet for said bumpstick.  So I don't know where 
(degreewise) it should be positioned.

So the other day I decide to slap the dial indicator and degree wheel on it 
to see what I have.  I have hydraulic lifters, so I removed the rocker rail 
and arms prior to the measurements.  Here are my measurements:

Intake opens 0.050 at 12 ATDC
Intake lift is approx 0.277 at the cam
Intake closed to 0.050 at 40 ABDC

Exh opens 0.050 at 42 BBDC
Exh lift is approx 0.288 at the cam
Exh closes to 0.050 at 68 ABDC

Computed quantites being:
Intake duration at 0.050 is 208 degrees
Exhaust duration at 0.050 is 220 degrees
Intake centerline is at 116 ATDC

Ok - so I get out the old Edelbrock book to look through Chrysler cams to 
see what I have, or at least something close.  Note that my cam is NOT an 
Edelbrock cam so we're talking "close match" here.

Based upon intake duration it looks like this cam would be somewhere between 
a performer and performer-rpm.

The problem is that Edelbrock locates their intake centerline at about 106 
degrees ATDC.  Compared to my measured/computed 116 degrees - looks like my 
cam might be somewhat retarded to the tune of about 8 or 10 degrees...

No Edelbrock 318 cam of any sort uses an intake centerline more than a 
degree away from 106 ATDC...  Likewise no listed cam has a intake open at 
0.050 at such a strange location as what I measured.

Does this make sense?  The motor runs ok, idles ok, but has minimal low end 
(<1300 rpm) power.  It does OK at the higher rpms (somewhat bad gas mileage 
still), but I need more low end since I'm turning a manual gearbox, etc...  
No - it didn't skip a tooth on the chain.  The dots line up just fine as 
they should.

Any help would be greatly appreciated.  I will be picking up my 
triple-keyway timing chain set tomorrow - and I intend to advance this cam 
and remeasure.

-Bill (trying to save a 318 instead of killing it like some folk on this 
list! :) )


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