timing belt tool? is it really needed?

[Goat Blower]

Yeah, I always set mine with two nails, a screwdriver and a 14mm wrench. It's pretty easy after doing it for the 50th time. The tool does make it easier yet though.

[Tachyon]

The absolutely fastest correct way to get the correct tension on a 4g63 motor is to have the threaded rod tool, and a .153" drill bit.

Insert the rod and use it to compress your tensioner's piston all the way. Then you can take a simple pry tool to aline the top two dimples horizontal to the ground as Jet mentioned. Back the threaded rod tool out and turn the engine twice, and double your timing marks. If all marks are perfect, try inserting the drill bit between the tensioner body and arm (see figure A in illustration).



If the gap is too tight and it does not insert, thread the rod all the way back in, and turn the pulley a bit more clockwise (so the dimple on the right is lower than the left). If the drill bit does not fit reasonably tight, repeat the above, but rotate the pulley counter clockwise (it takes very little adjustment)