The engine is as follows:
Superram, 383, 224/230 .537/.544.

The combo is not crazy extreme but likes to idle at about 850-900 rpm in park. I am starting with an ARAP base bin. Right now the car is idling real well, mid 130 BLM and no knock counts. My question is about the base timing. We all know that the tan/black wire needs to be disconected and base timing should be 6-8 degrees. Ok so now, I set my base to 6, I am having no problems, but i set it at about 900 rpm, is this fine?

So basically, is there a difference between setting my base timing to 6 at 900rpm Vs. 6 at the factory 550rpm? Should i be in park or drive? Anything else i need to know?

Thanks for the help guys!