Does anyone know how the timing marks go on my car?
86 Trans am 305 TPI
Is the center of the biggest valley 6 degrees TDC and then every point goes by 2? I am a little unclear because mine is rusted and I can't see.
THanks

anyone know?

The center of the biggest valley is 0 deg and it goes to a maximum of 12 deg at the top.

Is the next point 1 then the next valley 2 and so on? Or does it only count by the valleys?

IIRC, they count by 2, both on peaks and valleys. Clean it up with some steel wool and you'll see the marks. Or if you know the max is 12, you could interpolate and divide it up.

OK it was bugging me so I just checked mine. The first valley after the biggest one - towards the top - is 6 deg. They are spaced kinda funny, but after 6 deg, they go by 2's

so the biggest one is 0 degrees. and towards the two other notches is advanced so the smaller notch right next to big is 6 degrees and the small one next to it is 8?