It's been a while since I did any cam degreeing, so someone please check my math.

There's no place to attach anything I have as a good dial indicator mount, so here's my ghetto rig set up on #1 intake valve with a light checking spring - it appears to be stable:



The Diamante SOHC FSM spec is:

16* BTDC = Open
66* ABDC = Close

I won't be able to get the opening and closing points with a collapsed hydraulic lifter, so I've used the lobe C/L method as follows:

16 BTDC + 180 + 66 ABDC = 262/2 = 131 - 16 BTDC = 115* lobe C/L

I measured the intake opening to be 22* ATDC @ .050" lift and the closing to be 34* ABDC @ .050" lift and calculated the installed lobe C/L as follows:

180 - 22* ATDC + 34* ABDC = 192/2 = 96 + 22* ATDC = 118* installed lobe C/L.

Then, I brought the cam up to max lift and found the drop points before and after max lift and averaged both sides after several cycles.... that indicated 120* installed C/L.

I expect the difference is in lobe wear on the up ramp side, which would show a delay in the apparent C/L.

Anyway, from checking this cam and if my math is correct - it would appear to me that it's installed about 3-4* retarded - probably caused by milling the heads and deck.

Charley - have you ever checked any of these Diamante cams and if so, can you tell me what readings you got? More importantly, do you know if the lobes are supposed to be symmetrical? The variance I got due to the collapsed lifter is not the same on opening and closing angles - maybe that's a geometry thing, but it would seem to affect the calculated C/L.

Tomorrow, I'll remove the rocker assembly and try to take a reading directly off of the cam lobe. I also need to check the other cam.

Frank