I wouldn't even do a small block stroker if I was going to use it as a daily driver. By daily driver, I mean a car you are going to put 10,000 to 20,000 miles more per year. I did a post a while back to get MPG figures from people who had actually checked their milage VS those that just pull a number out of their ass. Do a search if you'd like.
Anyway...the 17 MPG I'm getting out of my 289 was better than most. That's WITH a automatic overdrive. The thing was getting more like 13 with the C4. THAT'S A 289!
If you want to daily drive it and you want the best situation in the world...I think you ought to do a 5.0 swap and go with the stock Ford EFI. Put in a T5 or an AOD and 3.55's and you'll have a car that will get with the program OR get 20+ MPG all day long. There is simply no comparison in drivability between a carb and EFI.
The only thing I prefer about the induction on my 289 vs the 5.0 in my '89 GT is how it looks. The electric choke on the holley is touchy. You have to let the car warm up for 5 - 10 minutes before you drive off in it in the morning. Despite my best efforts, the exhaust reeks of gasoline at idle. Etc. Etc. There's a reason Ford hasn't put a carb on a mustang in the last 20 years.
Phil
P.s. to answer your question, a 427 carbed stroker with a non-overdriven tranny and 3.55 gears or lower? I'll guess 7 MPG if you're getting on it...10 if you baby it.
