TIMING MARKS

The timing marks are spaced at 5 degree intervals for either the R16, or the U20 engines. 

The 0 degree mark is wider.  The narrower marks are spaced 5 degrees before top dead center from each other.  0 - 5 -10 - 15 - 20

If you have trouble seeing the timing marks with your timing light you might try rubbing chalk into the timing marks before you start the engine.

If you are running a smog distributor you need to follow the timing setting specified for your engine.  Setting a smog U20 12 degrees BTDC makes it run really nice.... BUT.  You will add strain to the upper timing chain, which can cause a variety of problems all beginning with stretching the chain, which is never good.  To allow for advanced timing settings you need to make sure you have a non-smog timing advance plate in your distributor.  These timing advance plates have the number 7.5 stamped into the bottom side of the plate.

Gary Boone offers a non-smog timing advance kit, or better yet an electronic distributor conversion kit so many owners have raved about after installing in their cars.