There is a 4.0 out there now, however I get more speed from a r-spec or dks 3.4 atm. Trying formula 34 soon. 3.8s havent been to reliable for me and are slugish on starts
i would say a 3.5 and 9:1(or whaever it is) would be great for a semi drag track. a techniqle track, i would say 2.6/3.0 and 12:1, becasue you will be constantly slowing down, and taking off agin.