Car Weight
I've seen some A-body SB vs B-body BB competition that appears to be very close if there is a tight budget cap? Say $3k from rolling body beginnings? Where weight does Play roll in final ET.
In this age of big power options. And big $$ builds. Setup and balance seems to dictate fast from nice try than trimming a few pounds here and there. That comes into play far more in Stock/Super Stock classes. Where shaving here and there makes the difference between advancing or trailer. But in the world of Outlaws? It's setup. And adapting that setup to conditions.