Thank you. It's not my wagon (which isn't nice), but it will do lol
Your 60ft. is mostly how the car launches. Yes if you put a higher stall it will help the 60ft. another thing that will help is putting in a cam on a 110° or narrower LCA, that's because it builds low end torque. My car right now has a 1.55 to 1.60 60ft. and a lot depends on the weather and if the car hooks, I have run 1.48 60ft times with my 406 years ago with the car just as it is why? because it make more torque. Another thing to think of is tires, radial slicks or drag radials. You are on the right track with your car and I would not over gear the car as I think mine is right now. Your car is fantastic for having 2.56 gears you should be commended for making that big car running those times. That 4000 lb. car would most likely run easy 12's if you were to cut about 10° duration and narrow the LCA on the cam you have now as again, it will make more torque. You are right, a big old 496 will make a ton of it.
My 406 in my wagon would 60' 1.71 off the hose, using the same 10" Hughes converter I plan on trying in the MC. Using the same 10" with this same 467 (albeit with manifolds) in the wagon, the difference was astounding. I found the 467 hit the tires harder than the 406 on spray for the first 5 feet, then you can feel yourself come out of your seat due to lack of acceleration. My conclusion is, the 467 indeed makes more torque initially, then lacks the horsepower to keep you in the seat...hence only covering the first 60' in 1.84 seconds, even though the first 5 feet felt faster.
Anyhow, it's interesting to note, the 467 in the Monte Carlo, with stock converter and 2.56 gears, feels more like my 406 off the spray in regards to initial thrust, followed up by a steady pressure in the seat. What I'm saying is, there is not that huge spike in power, followed quickly by noticeable disappointment. Don't get me wrong, this 238/248 cam certainly exhibits a noticeable powerband which starts about 30-35 mph and continues up to about 65 mph (shift at 70 mph), but you don't fall out of the seat like I did in the wagon with the 10" Hughes converter and 3.42 gears. The engine certainly felt over-converter'd in the wagon and I certainly believe it will feel similar with the 2.56 gears too.
I believe you are right, a smaller cam would help 60' times with stock gear, it would have more torque, and hit the lower-rpm powerband quicker. That's why I believe the cam I have now, on a 114°, would be better matched to the 496. Only running street tires, I'm hesitant of dropping down to a 106-108 for fear the mid-range torque (especially on a cam which is already relatively small) might spin the tires at the 60' due to high torque production.
I'm looking for steady, smooth acceleration that uses good torque to keep pinning you back in the seat the faster you rev the engine. Keeping in mind, with the 2.56 gears, I need to have enough top end charge to satisfy a car typically geared with 3.73s in order to avoid shifting to drive.
My question and curiosity is, will a 496 with the 238/248 cam make enough torque to drop .2-.3 tenths off the 60' with the stock converter and breath well enough to run out the backdoor?