Can you be more specific about the way it behaves when it maxes out on speed? does it buck and sputter, or just not produce any power, but run fairly smoothly? Does it idle normally?

Does it simply produce very little power, such that it would wind up to a high RPM if you kept it in low gear, or is it limited to not much more than idle RPM?

To check for a strong spark, unplug the coil wire from the distributor cap and secure it so that the spark has to jump about a quarter of an inch (no more than half an inch!) to engine ground. Have someone crank the engine and see if you have a blue spark. Yellow spark = weak. Clean all connections before replacing anything.

I presume that you loosened the timing belt cover and checked to be sure that the timing belt is good and tight, and could not have jumped a tooth, right?

If the spark and timing are good, the next thing to check is fuel pressure. You'd better get you book for that one. If you fuel filter is old, you could try replacing that before you go too far down the diagnosis trail.