Question on GT40 Heads vs GT40P Heads

[KansasCityGTS]

I know GT40P heads have smaller exhaust runners and the spark plugs are at a different angle which mean you need special headers. But, I know the Ford Explorer at one time used actual GT40 heads before they switched to the common GT40P heads. At what year did this switch take place? Then, what is the year range that uses actual GT40 heads?

Thank you in advanced.

 

[lang williams]

the change happened in mid 97 so some 97's had p's an some had gt 40. the gtp's flowed better the the gt's an had slightly higher compression.

 

[thumper460]

Ps are the better heads with the improved exhaust runner and plug location and chambers.. the Ps will out floe the 40s in the exhaust, and yet is uses a smaller valve size!! cool , huh??

The header issues can be fixed with a shorter spark plug/ 45* angle boots/ or a small ding to clear.

Either heads are great!! Ported they are even better!!

Just me...........................

Thumper