depends what year they are from and casting#. look for the first four digits of the casting# should be a letter, a number, followed by two more letters. like e7te or f4tz. not many 351 heads will help you unless you have the right ones. some will in fact hurt performance.
you will need some stepped head bolt/stud washers since the holes in the cylinder heads are made for 351s (no big deal, i have and extra set i will let go for dirt cheap) The only other problem you will have is there are NO smog ports on these heads so i dont know how that is going to effect the computer !
I just put on a set of Dooe 351 heads and a lunati cam. I'm having timing issues. I currently have 20 degrees of timing. The passenger side header starts to glow if I try to back off on timing. Any one else ever had this problem?
i bought a set, looked at them, compared them to my old set of 289 heads, promptly sold them and bought a cheap set of ported, stock heads. Basically, if you have to pay much for them they're not worth it in my opinion.
The W heads are the SAME as the 5.0 heads ( today) only the head bolt holes are larger for the 1/2 head bolts on the W engine!! Back in the day ( 1969 and 1970 ) the W heads were different... but to have those OLD heads re-worked for unleaded gas.. possible valve guides/ valves/ and hardened exhaust seats... make them kinda pricey!! Cool?? AND the Chamber CC's are at 69 vs the 62 of the E7s or the 54 of the 289s..!! Huge power loss...!
SOOOOooooo..... snag a set of GT40s.. or Port the E7s.. the power is there at half the cost of re-doing the C9/D0 heads...
Hope that helped..