What is a PI Head ?

Thread Tools
 
Search this Thread
 
  #1  
Old 03-06-2005, 05:18 PM
Modified 99's Avatar
Modified 99
Modified 99 is offline
Senior User
Thread Starter
Join Date: Feb 2005
Location: Ft. Worth, TX
Posts: 285
Likes: 0
Received 0 Likes on 0 Posts
Red face What is a PI Head ?

What is a PI head and how are they identified?
 
  #2  
Old 03-06-2005, 07:00 PM
Ted98's Avatar
Ted98
Ted98 is offline
Junior User
Join Date: Aug 2002
Posts: 96
Likes: 0
Received 0 Likes on 0 Posts
In a nutshell, PI heads outflow the non-PI heads. The exhaust valve is 2mm larger and the ports are shaped better to allow more air in/out. The combustion chamber is heart-shaped and the intake ports are square shaped instead of tear drop.

Ford started putting the PI heads on the cars in '99 I believe. I think they started putting them on the 5.4 trucks in '99 as well. The 4.6 truck didn't get them until '00 or '01.


"PI" should be stamped on the outside of the head. But you can easily identify the PI head by the shape of the combustion chamber and intake port.

If you scroll down on the below page, I have pictures of the PI and non-PI heads.

PI and non-PI heads
 
  #3  
Old 03-06-2005, 08:37 PM
ohioclint's Avatar
ohioclint
ohioclint is offline
Senior User
Join Date: Sep 2004
Location: Dayton, OH
Posts: 150
Likes: 0
Received 0 Likes on 0 Posts
WOW! Thats a nice informational page.
Thanks for the insight.

Clint

99 Expedition EB 5.4 4WD Etc.
 
  #4  
Old 03-08-2005, 07:02 PM
MBDiagMan's Avatar
MBDiagMan
MBDiagMan is offline
Posting Guru
Join Date: Dec 2004
Location: NE Texas
Posts: 2,218
Likes: 0
Received 1 Like on 1 Post
In the EXCELLENT book: 4.6 Ford Engines by Sean Hyland he indicates that the Performance Improved heads were released in 1999.

He says that a common cause of thread damage in the spark plug holes is removing the plugs while the engine is still hot.

Good luck,
Doc
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
onadraw
Modular V8 (4.6L, 5.4L)
3
04-06-2015 11:14 PM
terryswafford
Modular V10 (6.8l)
2
09-18-2010 12:32 AM
BURNSTOUGHFORD
1997 - 2003 F150
64
02-21-2009 07:23 PM
Bliath
Modular V8 (4.6L, 5.4L)
2
02-09-2005 06:02 PM
MGT351
Modular V8 (4.6L, 5.4L)
2
08-09-2002 09:47 AM



Quick Reply: What is a PI Head ?



All times are GMT -5. The time now is 06:46 PM.