Hi everybody,

I'm experiencing with timing problem of my M116.980 engine. After replacing my original camshafts which has code number 46/47 with 52/53. Engine started running unstable at idle. When I move distributor to advance position,engine become more stable, if I move retard position engine becomes unstable.

Therefore,when I check valve timing specifications of Camshafts 46/47 and 52/53 I realized that they have different timing values,

For camshaft having code 46/47,
Inlet Valve opens BTDC at 19 degrees closes ABDC 53 degrees,
Exhaust valve opens BBDC 42 degrees, closes ATDC 20 degrees

For the the camshaft 52/53,
Inlet valve opens BTDC 26 degrees and closes ABDC 44 degrees,
Exhause valve opens BBDC 60 degrees and closes ATDC 14 degrees

So, could you please tell me why there are 3 different camshafts each has different valve timings for M116 3.5 engine.

Secondly, Can I correct my current valve timing values which 52/53 currently installed to 46/47 by replacing woodruff keys with specific offset to each camshaft gear? If so, could you please tell me offset value?

Finally, according to the valve timing values, which camshaft provides more compression? (If available, or any relation)

Thank you very much for support and information in advance..

Regards,

Kutluhan