I hope you are talking 1/8 mile, I removed my one barrel carb and did this to my little 170/6 and It likes the hwy speeds and I am running all stock little 170 cu /6 and can get a 11.90 1/8 mile. To get where you are wanting you will need allot of port work on your head and shave at least 100k of the head to bring your compression up and larger valves and stronger springs and then a good header so it can breath. Dan is one of our great /6 gurus and he keeps me strait :happy10: and No a four barrel will not blow up a /6.....
Me, I picked up an easy 8 to 10 miles to the gallon and she jumps in and out of traffic as good as a 273 I think. I built this as a daily driver and love the extra hp, it don't take mush to push 2.700 car. and yes , I like opening my hood and see my system I have.