The "came to a quick stop" event could have "unloaded" the Timing Belt tension, if the belt was old or stretched for any reason, causing it to jump several teeth at the crank sprocket.

The one time I've actually seen this happen (new belt but not properly retensioned at 600 miles), it caused a no-start on a 240). But I suppose the amount of "slippage" could vary, as could the symptoms.

I would get the #1 piston at TDC compression according to the crank pulley mark (keeping in mind that it can also slip) and then check the first two cam lobes. If the crank and cam shafts are still in correct time:
#1 should be pointing almost horizontally inboard
#2 should be pointing outboard, and upward about ~30°.

If the cams look wrong, The balance/puller mark may be wrong, so double-check that the piston really is at TDC by feeling the piston top with some kind of thin probe through the sparkplug hole, while rocking the crankshaft with a 15/16" socket on the crank pulley bolt.
--
Bruce Young
'93 940-NA (current), 240s (one V8), 140s, 122s, since '63.