i have a 89 gta with a comp cam hydraulic flat tappet cam and like the book says and comp cams said i installed it with crank sprocket at 12 and cam at 6 o'clock but my problem is that the lobes on the cam are opening the valves when they should be closed example #1 tdc it says adjust 1 intake and the other vavles but cam lobes are keeping lifters up but if i go crank 12 oclock cam sproket 12 oclock it seems to be fine was the comp tech guy wrong?any one else have this problem? the cam # is 12-268-4

 

they tell you to install it that way to make it easy to line up so you dont end up installing the chain a tooth off. You are correct, that is 180 out, thats why after you install the chain you crank it over 180 before to have it in time with both marks at 12.

 

okay maybe this will be a little easyer to understand... there is nothing wrong with your cam installation... however you installed the distributer pointing to the wrong terminal...

 

There is no problem with the installation instructions.

When you install the timing chain with the crank dot at 12:00 and the cam dot at 6:00, you are actually on #6 firing.

The reason you install it at that point instead of at #1 firing, is because it's A WHOLE LOT easier to see its alignment and get it right when it's "dot to dot", than at the "both dots at 12:00" position (#1 firing).

Put it together that way; then rotate the crank ONE FULL REVOLUTION (360°). At that point, both dots will be at 12:00, and it will be at #1 firing. With it at this new location, drop the dist in such that the rotor points to the #1 terminal (just to the driver's side of straight ahead) when the dist is fully seated.