1970 Mustang Straight 6 to a 2007 V6

The 4.0 OHC engine has some serious issues. I would swap in a 5.0 fuel injected which will give you lots of power and probably as much fuel economy as the 4.0. When you are done I rather doubt you will gain any economy over the original 6. Another option you should consider is fuel injection for your original engine (coolest option).

Link. http://www.mustangandfords.com/how-to/engine/1811-six-appeal-building-a-200ci- inline-six-engine-for-todays-driving/

I would add that a simple carb swap would fix the alcohol related issues, give you more power and fuel economy and the cost is minimal.

There are aftermarket wire harnesses for modern engines to adapt them to older cars. Check all the speed catalogs sites like Summit, Jegs, etc., or Google 'standalone wire harness' or 'EFI harness'. You may also want to look into EFI kits for older engines, although I doubt they're made for something like your 200cid, but couldn't hurt to look.

There are quite a few goodies for the Ford inline 6's. A new head is the single best thing you can do for the 200/250 engines.

Head. http://www.mustangandfords.com/how-to/engine/1804-finally-a-performance-cylinder- head-for-ford-six-cylinders