Like I said..I have a 71 Demon.It was a original 340 4-speed car...we got it as a bare bones body in 1981.It now has a 440,it's been tubbed,fenderwells cut for headers,no interior etc..
We should have just put in a small block and raced it that way with 9" tires..would have accomplished the same results.

Put in a stroker 360 and run 11.50's with it.It doesn't pay an more money at the tracks to run faster.