ok so i know this has probably been discussed on here a million times but i keep getting conflicting answer so maybe somebody can help me..l31 vortec tpi intake idling around 2000 rpm,had custom chip made,did same thing on stock chip,stock motor,checked iac,tps,etc. so i think i have my timing advanced a little to much causing my problem. i know i need to be at 6*BTDC(stock) and the motor is currently directly on tdc. so in order to get it to 6*btdc do i need the timing mark to be to the right(clockwise)or the left(counter clockwise) of the tdc mark to get it 6*btdc???l31 on has one mark on it for tdc so im going to have to guess 6* but i know its not very much off tdc..6*BTDC IS IT RIGHT OR LEFT OF THE TDC MARK???thanks

 

The engine runs clockwise. Therefore, for the ignition to fire before TDC, the timing mark, as observed with a timing light is to the left (counter-clockwise with respect to engine rotation) of the TDC mark on the timing tab.

It's out of focus, but this should give you an idea. 6-degrees BTDC is the "valley" between the 4-degree and 8-degree "peaks".

 

THANKS