My old DartSport had an M1 single plane and 1050 Dominator running in the 10 flat range with a best of 9.96 on a real cold day.
I switched to an M1 low deck tunnel ram with 2 750 Quickfuel carbs and the car was a whole new animal. It started and idled better in any kind of weather as long as it was over 35 degrees. Ran consistant 9.90's with a best of 9.88. Footbraked to a 1.36 60 foot, this was an 11 to 1 compression 451 with the MP 590 purple shaft solid cam.