My numbers are way off from the cam card. This is a Web 86A.
Granted, this is my first time degreeing a cam. Am I missing something, or is this a bad cam?
The card reads:
IO 18 deg before TDC
IC 54 deg after BDC
EO 54 deg before BDC
EC 18 deg after TDC
I mounted a huge degree wheel on the crank, made a pointer, found TDC. In my first round of measurements I placed my dial indicator on a modified lifter, with the case halves assembled. The numbers didn't make sense. Maybe I didn't grind the end of my lifter tool perfectly square and it was rotating in its bore? In any case, I decided to eliminate that variable. I split the case and put my indicator directly on the cam lobes.
I will be using 1.4 ratio rockers. Therefore, I reasoned, the checking clearance of .050 lift at the valves corresponds to .050/1.4 = .036 lift at the cam.
After making sure I was getting solid, repeatable measurements, here is what I have. These numbers are at .036 lift at the cam.
IO 23 deg before TDC
IC 38 deg after BDC
EO 46 deg before BDC
EC 16 deg after TDC
If it was simply a matter of the cam gear being mis-indexed, the numbers would be consistently advanced or retarded. But they are all over the map. The intake closing event is 16 degrees off! The lobe center on the #1 intake lobe works out to 97.5 degrees; it is supposed to be 108 degrees.
Is this a bad cam?
Do you like to go fast? Well get out of that stocker and build a hipo motor for your VW. Come here to talk with others who like to drive fast.
Moderator: Tom Notch
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