360 timing question

After carefully reading the WSM , i have a question regarding the timing : intake valves open at 10 degree before TDC and exhaust valves close at 9 degrees after TDC. When you time the intake valves you reset dial gauge at TDC of compression cycle and 360 degrees later you measure 0.60mm at side intake valves. For exhaust why would you reset at 9 degrees before TDC and measure 1.66mm when you pass TDC ?? Shouldn't you reset dial gauge at TDC and measure how much the needle moves until the valve closes at 9 degrees after TDC ?

 

What is the significance of 9 degrees before TDC for exhaust valves ? (Remember intake valves start at 10 degrees before TDC)

 

Well, you put the dial gauge in the spark plug hole and watch how the needle moves. The moment the needle stops moving in positive direction and starts to move in negative direction, you set find by approximation the TDC and set the degree wheel. Next you pick two arbitrary points (3mm before and 3mm after TDC) and measure the degrees. If they match, then you are ok. If one is lets say 17 degres and the other is 16, you move the degree wheel needle half a degree so that you have 16.5 anc 16.5

 

Just to clarify my question : If you are doing overlap for setting the timing on the 360 (intake opens at 10 degrees BTDC and exhaust closes at 9 degrees ATDC) why would you reset the dial gauge on the exhaust valve at 9 degrees instead of 10 degrees BTDC ?? (You want the exact moment the intake opens to reset dial gauge for exhaust) Could you possibly fix timing without degree wheel just with dial gauge on intake valve to exact moment it opens ??!!!

 

Ok, so let then clarify something else...

-For intake, you reset dial gauge on TDC of combustion cycle and rotate 360 degrees crankshaft to measure 1.66 mm at TDC of intake cycle.

-For exhaust, you reset dial gauge at 9 degrees prior to TDC on exhaust cycle, and measure 0.60 mm when ?? On WSM is says : "Rotate crankshaft further until the dial gauge indicator is stable on value and the bucket proves to rotate freely in its housing."
From what I understand you pass TDC and continue to rotate further until exhaust valve closes completely. Correct?

 

Another issue that could be a typo on the WSM for the 360 :

I was looking into the WSM of the F355 (which is a similar motor as the 360) and it has the following specifications :

Intake :
Opens before TDC 16 degrees
Closes after BDC 42 degrees

Exhaust :
Opens before BDC 56 degrees
Closes after TDC 16 degrees

The way overlap of the camshafts is done is :
INTAKE : find TDC in compression cycle, reset counter for dial indicator, rotate crank 360 degrees and measure 2.41mm at TDC for intake side valves.
EXHAUST : find TDC in exhaust/intake cycle, reset counter for dial indicator, rotate crank until buckets rotate freely (valves have closed) and measure 2.29mm

For the Ferrari 360 Modena :

Intake :
Opens before TDC 10 degrees
Closes after BDC 50 degrees

Exhaust :
Opens before BDC 76 degrees
Closes after TDC 9 degrees

The way overlap of the camshafts is done is :
INTAKE : find TDC in compression cycle, reset counter for dial indicator, rotate crank 360 degrees and measure 1.66mm at TDC for intake side valves.
EXHAUST : FIND 9 DEGREES BEFORE TDC IN EXHAUST/INTAKE, RESET COUNTER FOR DIAL INDICATOR, ROTATE CRANK UNTIL BUCKETS ROTATE FREELY AND MEASURE 0.60mm

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BOLD text above is the weird part of timing...

Please note that in the 360 Modena the way you measure Exhaust Valve opening is counter-intuitive !!! Why reset at 9 degrees BTDC and not at TDC ?????? Did Ferrari mean to measure 9 degrees before the Exhaust valves close (which in effect is TDC, because exhaust valves close at 9 degrees ATDC ???)

Thanks ! I think I beat this issue to death, but it is because my car feels strange even after I did overlap exactly as WSM !!! Help?