The easist way to time your engine is with a vacuum gauge-forget the timing mark on the crank pulley, most of them aren't even close (mine shows over 25 BTDC at 900 rpm idle, when it is actually closer to 18 BTDC). Hook the vacuum gauge up to the port that always has vacuum (usually drivers side) and advance the timing while adjusting the fuel mixture/idle speed until you get the highest possible vacuum reading. Next, retard the timing slowly until the vaccum reading drops 1/2'' to 1", lock it down and go for a test drive. If it pings on acceleration, retard it in 1/2" increments until it stops.