If your '65 has the original cam grind --Volvo "A", I presume-- there is a procedure in the service manual to check externally the cam to crank timing.

With the intake valve of #1 (or #4) cylinder re-set temporarily to 1.1mm clearance (0.043 in.) that valve should begin to open as the crank passes the 10 degrees after top dead center mark on the front pulley.

I only have the spec for the A-cammed B18D, from the 544 manual. A longer-duration cam will have the intake, at a similar wide clearance, open sooner, more toward 0 deg. The artificially wide clearance is to avoid involving the clearance ramp on the cam lobe and get a more decisive, abrupt sign of valve opening. And either #1 or #4 intake will begin opening when the crank pulley marks are in that range. One tooth off amounts to some 17 degrees of crank rotation to get the cam lobes to the same place, for a 21-tooth crank gear.

Charles Greenlaw, Sacramento CA