OD off, that way your car wont try to switch into 4th right before the finish line, unless your just racing on the street and will be racing for more than 1/4 mile then leave it on

and I havent decided yet if its better to leave it in first.

I was just trying today and I decided I like it with the gear selector in 2nd and when I want to switch I just slide the selector up to 3rd or you can redline and the tranny is supposed to switch up to 3rd

But I thought I read somewhere that our trannies will only automatically upshift if the selector is in 1st and not second but I think it will auto upshift if your in 2nd too. if thats the case leave it in 2nd that way your not redlining 1st

1998 dodge avenger 4 cyl AT
Mods are:
Not enough