If I do a compete tune up, do i have to change the timing of the engine?

How do i change the timing of the engine?

I have a first gen protege. 1990 LX 5 speed

 

You don't have to change the timing, but you should check it. And the BPs run a little better with more timing advance (about 14 degrees BTDC, spec is 10 +/- 1).

To check the timing, you'll need a timing light. Hook it up to the number one cylinder, and point the timing light at the timing mark on the front of the engine (main pulley, towards the front of the car). It's easier to see without the AC/PS belt in place, but it's never easy to see. You also need to run a wire jumper from the "ten" to "gnd" on the diagnostic connector, near the firewall above the battery. Doing this keeps the computer from adjusting the timing while you are doing it too.

The distributor is adjusted by loosing the two bolts at the base (12mm wrench or socket) and rotating it.

There is probably more detailed info in the FAQ, or on Mazdaspeedwest's siteMazdaSpeedWest's site