Not much! Drop in a 460 crank and pistons, a small cam, Stealth intake, Holley carb, and a set of headers. In 72, BBFs had really decent heads for production cast iron. Easy cheezy. Edit: If you want to leave the basic engine stock, you can... It is just sort of a waste to have so much weight, but use the smallest possible cubes. You can keep the long block stock and just plug in the other stuff and have your 400+ HP. Even more if you pull the heads off long enough to port them and rework them a little. Maybe shave them ever so slightly. Not enough to need to shave the intake. Just enough to make them super flat again and gain the tiny increase in compression as 72 was down in that department.
thanks for the info i would like to keep the bottom end stock. i will probably throw a set rings and bearings in, if i can get bye with that.
Like was said before...not a difficult proposition to get 400 hp plus. The stock bottom end is plenty stout. I had a stock CJ bottom end that ran 11's in a 3900 lb car. The cobra jet heads flowed like mad. Try and get a 1970 version of the block, they are the same as the CJ only without the 4 bolt mains. If I remember correctly the factory hp on the 70 CJ was 385. GREAT motors! I'd do one again if it would actually fit in the bay of the Maverick without putting an MII or struts under it.
You could be right. I know that the 70 was the thick wall block and it could have gone to 72. Good luck with it! They are great motors!
Beware, most of the 429's out of cars had "square bolt" passenger car rods. I have ran them to 400hp but thought I might be on borrowed time. The "football" truck rods or CJ rods will take a lot more. A set of Eagle I beam rods is a real good (and relatively cheap) investment for these motors. When you go to 460Ford.com do a search on "Block Summit". Those guys put a lot of work into weighing, measuring, and sonic testing several blocks. 70's should have a D0VE casting number. Pretty much everything from 71 to 78 will have a D1VE block casting number. Cleaver