Time for another episode of "Phil's Believe it or Not"...

Contrary to popular belief, a stock B20 should not have a noisy valvetrain. Particularly not a B20E or F, which have the "D" cam. The Volvo Green Book specs for valve lash are "one size fits all," even though the various cams are truly spec'd differently, so dealer mechanics wouldn't have to sort out which is which. The adjustment technique is also one designed to get cars through dealer service bays as quickly as possible.

Result: 1) Lots of valve noise, and 2) cam lobes wiped out under 100K miles. You know that reputation -- neither need be so. Uncle Olaf did not design stupid motors.

The design spec for the "D" cam is .015" -- adjust for this with the engine hot. If you really insist on doing it cold, use .017" (not quite as accurate).

Method:
Turn the motor only in the direction it runs (CW looking at it from the front of the car).

When you see an exhaust valve just start to open (rocker moves downwards), adjust the intake valve on that cylinder. Do all four intake valves similarly. Then:

When you see an intake valve just start to close (rocker starts to move up from fully down), adjust the exhaust valve on that cylinder. Do all four exhaust valves similarly.

Feeler gauges are not GO / NO-GO gauges. They are feeler gauges, and require some feel. When adjusting, push down hard with the screwdriver on the adjuster and set it so there is some slight drag on the feeler. Snug the locking nut (snug is all that's needed) and recheck, continuing to push down hard with the screwdriver. Err on the side of tightness.

You should have hardly ANY clatter with a warm motor.

(Note: the Haynes manual technique is theoretically perfect, but is less accurate because of flex in the valvetrain. The end valves always turn out .001-.002" looser than the middle ones. Any other method that has you adjust two valves between turning the crank is garbage.)

8^)