906 or 452 which is best overall

The good news is, engine wise, to get into the high 11's with a 440 in a Dart, you can probably do it with 8.5:1 compression, properly prepped Stealth heads, an Edelbrock RPM Performer intake, 850cfm 4 bbl and a 240-245 degree @ .050" hydraulic flat tappet cam. Done right, that's a 450 HP engine and you are under 12 seconds.

That literally is almost identical to my engine combo. and 11.74@114.