How to get a 351w in a 81 foxbody?
A 351w swap into a fox is fairly straight forward. However you may run into issues with 2.3 k-member, I'm not totally sure on that one. You will need 351w swap headers, 5.0l convertible motor mounts are recommended, the t-5 is compatible with 351w because the bell housings for the 302 and 351w are the same. A c4 auto will fit your fox, the bell housings for the 5.0 and 351w are the same in this case too. Also, are you going fuel injected or carbed? If you're going fuel injected you need to relocate the battery to either the trunk/hatch or to the driver's side of the engine compartment, also I recommend swapping the truck efi intake for a aftermarket or ford racing intake. Then either get a aftermarket cold air intake, or a stock 5.0l intake. Then you need a mass air harness and computer. If you go carbed it's pretty straight forward. Hood clearance becomes an issue either way(hence the reason for the convertible motor mounts), look for aftermarket hood or a cut hole in the factory hood and add a scoop. You will also need a larger radiator. Also, consider upgrading the rear end to a 8.8 or 9 inch. Sub-frame connectors should be installed. Upgraded brakes and suspension is highly recommended. 87-up spindles, rotors, and calipers at the minimum. You can use sn95(94-96) parts if you want 5lugs and rear discs, if you have the extra cash. Definitly upgrade your front suspension to handle the weight of that 351. That's all I can think of for now. I'm sure other people will add more info. I'll add more if I think of it. Forgot about the oil pan, you need one specifically for this swap, ford racing makes one, so does mildon, and canton. Also, I've been told one from a late 70's LTD with a 351w would work, but I have never tried it. Also, If you want to run a serpetine belt you need to get swap brackets if want power steering. the pulleys from a 5.0 will swap over.