I've got the Rotary Performance main underdrive pully and it has four marks on it. I know one of them is no advance or retard; and one on either side is +- 10 degrees; but I don't know if the other one is + or - 20 degrees. So if anyone even knows which mark is at 0 degrees, I can figure out the rest. I tried calling RP and they must be closed today.

If I'm standing in front of the car and looking down at the pully there are four marks from left to right. The one one the furthest right is the most advance, and the furthest left is the most retard. How much advance and retard is really what I nedd to know.

91 NA

 

damn i can't remember, but im thinking its this
10 and 20 BTDC, 0, and 10 ATDC

 

Does that mean there is a 10 degree advance and a 10 and 20 degree retard? Or is there a 10 and 20 degree advance and only a 10 degree retard? I just want to advance my timing 20 degrees and right now I have it on the furthest mark to the right if you looking in from the front. But I notice a nice power gain if I go about the same distance as between the marks past the furthest mark on the right. But I don't want to ruin my motor.