I apologize upfront for this long email...but I really need help and I figure someone here can help figure out my problem. Here goes.
I purchased a used Anderson N-41 cam from a guy in Britton, MI. I have no way of confirming that it is truly a N-41 cam other than it had "N-41" scribed in the end of the cam. I didn't receive a cam card, but I did find one on the internet for this cam.
Anyways, I installed the cam dot-to-dot and then verified TDC. Then I used the intake centerline (ICL) method to degree the cam knowing from the cam card that the ICL should be at 106-degrees of crankshaft rotation. To use this method, I rotated the engine in the normal direction of rotation (clockwise) until I reached max lift of the intake valve. I then rotated the engine counter-clockwise until I reached .100". I then rotated the engine clockwise again until I reached .050" (this should be .050 before max lift) and took a reading from the degree wheel (it read 56-degrees). I then continued to rotate the engine clockwise until I reached max lift and continued past max lift until I reached .050" (this should be .050" after max lift) and took a reading from the degree wheel (it read 162-degrees). I added these two numbers together and divided by two (56+162 = 218/2 = 109-degrees). Because the cam card said to degree the cam to an intake centerline of 106, I determined that I needed to advance the cam 3-degrees.
So...I rotated everything back to TDC and then removed the timing chain. I then rotated the crankshaft clockwise 3-degrees and reinstalled the timing chain. I repeated exactly the process above and got readings of 53 and 159, respectively. Adding these up and dividing by two resulted in an intake centerline of exactly 106-degrees, just as the cam card specified.
So...everything's perfect, right? Wrong. Since this is my first cam install I decided to check my work using the procedure that Crane Cams recommends..."the duration at .050" lift." Using this method, I rotated the engine clockwise until the intake valve began to open. I continued to rotate the engine clockwise until the dial indicator read .050" and took a reading on the degree wheel (it read 24-degrees). I continued to rotate the engine clockwise until I reached maximum lift and took a reading on the dial indicator to compare with the max lift specification listed on the cam card (my indicator read 330 compared to 320 listed on the cam card). I continued to rotate the engine clockwise as the numbers on the dial indicator decreased to .050" and took a reading on the degree wheel (it read 53-degrees). I then compared these two degree readings with what is listed on the cam card and they are nowhere close. The cam card reads:
Timing events at .050: Intake 1/41, Exhaust 45/5
I double checked my readings but got the same results the second time. As you can imagine, this left me very frustrated and needing help. But I don't have anyone around that can help short of paying an engine builder to bail me out. I was hoping someone here could help me instead since there is so much expertise on this board.
So what do you guys think? Is my cam not the N-41 cam? Did I do one or both of the degreeing procedures wrong? Any insight anyone could provide would be much appreciated.
Thanks
Justin
I purchased a used Anderson N-41 cam from a guy in Britton, MI. I have no way of confirming that it is truly a N-41 cam other than it had "N-41" scribed in the end of the cam. I didn't receive a cam card, but I did find one on the internet for this cam.
Anyways, I installed the cam dot-to-dot and then verified TDC. Then I used the intake centerline (ICL) method to degree the cam knowing from the cam card that the ICL should be at 106-degrees of crankshaft rotation. To use this method, I rotated the engine in the normal direction of rotation (clockwise) until I reached max lift of the intake valve. I then rotated the engine counter-clockwise until I reached .100". I then rotated the engine clockwise again until I reached .050" (this should be .050 before max lift) and took a reading from the degree wheel (it read 56-degrees). I then continued to rotate the engine clockwise until I reached max lift and continued past max lift until I reached .050" (this should be .050" after max lift) and took a reading from the degree wheel (it read 162-degrees). I added these two numbers together and divided by two (56+162 = 218/2 = 109-degrees). Because the cam card said to degree the cam to an intake centerline of 106, I determined that I needed to advance the cam 3-degrees.
So...I rotated everything back to TDC and then removed the timing chain. I then rotated the crankshaft clockwise 3-degrees and reinstalled the timing chain. I repeated exactly the process above and got readings of 53 and 159, respectively. Adding these up and dividing by two resulted in an intake centerline of exactly 106-degrees, just as the cam card specified.
So...everything's perfect, right? Wrong. Since this is my first cam install I decided to check my work using the procedure that Crane Cams recommends..."the duration at .050" lift." Using this method, I rotated the engine clockwise until the intake valve began to open. I continued to rotate the engine clockwise until the dial indicator read .050" and took a reading on the degree wheel (it read 24-degrees). I continued to rotate the engine clockwise until I reached maximum lift and took a reading on the dial indicator to compare with the max lift specification listed on the cam card (my indicator read 330 compared to 320 listed on the cam card). I continued to rotate the engine clockwise as the numbers on the dial indicator decreased to .050" and took a reading on the degree wheel (it read 53-degrees). I then compared these two degree readings with what is listed on the cam card and they are nowhere close. The cam card reads:
Timing events at .050: Intake 1/41, Exhaust 45/5
I double checked my readings but got the same results the second time. As you can imagine, this left me very frustrated and needing help. But I don't have anyone around that can help short of paying an engine builder to bail me out. I was hoping someone here could help me instead since there is so much expertise on this board.
So what do you guys think? Is my cam not the N-41 cam? Did I do one or both of the degreeing procedures wrong? Any insight anyone could provide would be much appreciated.
Thanks
Justin