This one confuses everyone (me included).
- When you work on the disty you want #1 at TDC.
- When you work on the timing belt you want #4 at TDC.
Think
very carefully about this - #1 & #4 are at TDC at exactly the same time - TDC or Top Dead Center is when the piston is at the top of it's travel, and this will occur once for every revolution of the crankshaft. since this is a four stroke engine, it takes two revolutions of the crankshaft, to complete a cycle, and in these two revolutions, each piston will reach TDC twice, once at the end of the compression stroke, and once at the end of the exhaust stroke - this is a four cylinder, four stroke engine, so when #1 is at TDC on the compression stroke, #4 will be at TDC on the exhaust stroke,
but both are at TDC.