Timing Tab BTDC Question

[Randy S.]

On a 66 327 300HP small block my initial timing is supposed to be 6 DEG BTDC. Is this above the zero ( toward the hood)or below the zero ( toward the floor)on the timing tab? Since the motor rotates clockwise I would assume above the zero but there appears to be an R below the zero on the timing tab. Wouldn't R stand for retard and be before TDC? I cannot see any A on the tab.

The car runs fine now and timing is at 4 marks above the zero, just playing with my new dial back timing light.

Randy

[Rob A.]

Re: Timing Tab BTDC Question

You're correct that BTDC would be above the zero.(towards the hood)

[Joe L.]

Re: Timing Tab BTDC Question

Randy----

You will note that one end of the tab is marked "A", one end is marked "R" and it's marked "0" in the center. The "A" represents "advanced" or BTDC. The "R" represents "retarded" or ATDC. The "0" repesents the TDC mark.

[William C.]

Re: Timing Tab BTDC Question

The "A" line is 10 degress advanced.