gt40p heads?

montyd

Member
Mar 13, 2006
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i am looking at getting a set of heads off an explorer like everyone does. and i saw a forum on here where someone said there is a comparison of explorer and gt40 heads and the pros and cons of it on stangnet but i cant find it. does anyone know or have the link? any help would be appreciated thanks fellas
 
'96 to early '97 came with standard GT40's, while
mid '97-'01 came with P's.

-40's can be identified by 3 lines cast into the ends of the heads,and "GT" cast into the rocker valley and beside the lower rear head bolt hole.

P's have 4 lines and "GTP" cast into the same places.

P heads also have 58cc nominal chambers compared to 62-64cc for the standard-40's, as well as a smaller exhaust valve that promote's velocity, along with the spark plug relocated closer to the center of the chamber.

All told, P's are probably worth 10-15 hp over the regular 40's.

The relocated plug angle is why P's need specific headers.
 
montyd said:
so my shortys that are on my car now wont work with the new head from an explorer?

Depends what year explorer... '96 and early 97's have standard GT40's, so you would be fine.

If they are off of a mid-97 -01, they are P's and require a P specific header... FRPP and MAC make P shorty's, and, while nor designed for P's, BBK and MAC long tubes do work.
 
in my opinion, the differences functionally are negligeable and debateable. The only difference imo worth considering is that the spark plug angles of the p heads require ford racing shorty p headers, or mac p headers (garbage), or some wicked 90 boots and customizing on headers. Not a big deal though, those ford headers are just over $200 on summit in stainless form, and give you tons of access to the plugs.
 
Tri-state offers some p's with 1.94/1.54 valves. I understand that factory was 1.84/1.46. Are the larger valves a good improvent over stock for this peticular head?
 
Lxstang306 said:
gt40p have diff exhuast ports thats why not all headers will fit them spark plugs have been moved to.

The exhaust ports on GT-40P heads cause no issues with just about any small block ford headers. The exhaust ports are a "redesigned" port in comparison to an E7TE head or a standard GT-40, but they are not a raised port or anything else that would require different headers. The only reason they require unique headers is because of the revised plug angle.