witch has more horse power thinking about putting 4.6 in 87 tbird
The 4.6 out of the '03-'04 Cobra made right around 400 horse, but you'll likely not find one for sale unless someone has a wrecked car..
Most of the 351w that are worthy of straight swapping were either in the first gen Lightnings, or the '95 Cobra R Mustang. As with the Termi Cobras, you'll most likely not find a Cobra R being parted.
The 4.6 will make more power and with more money spent, whereas the Windsor is easier, less complicated, and slightly less efficient.
I'd find a junkyard Mark VIII, and use it's engine as my departure point. It would get a few performance upgrade. Pretty easy to get one in the 300 horse mark. Or just toss a supercharger on it.
You may wanna check this out before starting on a 4.6 swap(be sure to check out the pictures link)...
http://natomessageboard.com/ubbthreads.php?ubb=showflat&Number=247500#Post247500
thanks for the reply I have a mark 8 runs good less then 100k and 351w 40 over cam aluminum heads an intake a holley 700 double pumper don,t have the top end put together yet still need rockers just not sure witch root to take