Cam timing on 355

Quick question.

When doing a belt service on a ferrari 355, when setting up the cam timing, do you just set cyclinder # 1 at top dead centre, and move the cams so they align with the marks, and then just put the belt on, tighten with the tensioner and thats it.

 

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The marks get you in the ball park--that is the engine will turn over and not bend valves.

There are 32 teeth on the pulley to belt interface or 11 degrees 15 minutes per tooth
There are 18 holes in the pulley to cam interface or 24 degrees/hole
There are 14 teeth in the cam shaft face set at 22 degrees 30 minutes
So, there is a hole on the cam for every 2 teeth on the belt,
By playing with which tooth on the belt and which holes are sellected for the dowel, one can set timing to better than 1 degree 30 minutes.

Rotate the engine until #1 cylinder TDC.
Assemble the Camshafts, pulleys, and belts
Fit tensioners
Stretch the belts so tension wheel has 2.5mm of clearance

Observe that intake cam is on an intake phase
Place dial indicator on outside bowl of #1 cylinder intake
Zero dial indicator while tappet is on base circle of intake cam
Rotate camshaft until dial indicator reads 2.41mm
Observe the alignment betrween the pulley holes and the cam timing holes.
One of these holes will be best aligned with the cam holes
Insert retaining dowel in this combination of holes
Torque retaining nut to 8.8N.

Observe that the exhause cam is on an exhaust phase
Place dial indicator on exhaust valve tappet
Zero dial indicator while tappet is on base circle of exhaust cam
Rotate camshaft until a dial indicator reads 2.29mm
Observe the alignment betrween the pulley holes and the cam timing holes.
One of these holes will be best aligned with the cam holes
Insert retaining dowel in this combination of holes
Torque retaining nut to 8.8N.

Rotate engine 270 degrees (repeat as above)
Rotate engine 450 degrees and recheck #1 cylinder cam indicator readings
Rotate engine 270 degrees and recheck #8 cyclinder cam indicator readings