No one makes an intake to use 4v heads on an M though... I have seen one 4v M that they welded a big blob around each runner on an aluminum 2v M intake to make sure the ports sealed. I have also seen aluminum plates that bolt to the head and then you can bolt a 4v C intake on, but never seen it on an engine. Also, the M simply won't go into a Maverick with towers. Even shaved towers. You have to go M2 and use a 460 trans, so personally I would use the 460 engine too after all that trouble. You also would have to build custom headers as you would for a 460. You can build a 427w and have a much lighter engine, same cubes, keep shaved towers, and use off the shelf headers and engine mounts. Even a 427c has all the same benefits.
We are in agreement on the 400. Not a good option for the Mav. The dyno test I saw used the Edelbrock Performer with the 4V heads. Even though the runners on the intake were smaller than the runners on the heads, it made very good power. The article did not talk to sealing problems. With that said, 2V heads will make good power, so why bother. The bucks up way is to use the Aussie heads, or aftermarket aluminum versions. But, that takes away any budget build concept, especially for use in a pickup. The stroked 351Ws have the tight fit problems that we all know about. The stroked 351Cs, as we all know, fit easier. I wouldn't even consider the 460, unless I just had money to spend and wanted to be different. The 347 is, IMO, the best fit, NPI, for the Mav. Pretty easy to get to the 500hp level and in the car. As a general rule of thumb, a given hp level goes faster in a light car.
