Changing heads
Thread Starter
|
Member
Joined: Aug 2004
Posts: 34
Likes: 0
From: Newnan GA
Changing heads
I also am changing heads on my truck after a blown plug. I have a few questions and concerns about this topic that are still unclear to me after doing hours of "SEARCH"!!! I know there are several other answers out there but I want to do it right becauer I travel across the country with a trailer and dont want this happening again over 800 miles from home.
1. I have a 99 F150 5.4L, Does my truck have PI heads or non-PI heads, and do PI heads have more threads than non PI heads?
2. Is there a difference between the upper/lower intake on PI heads vs. non PI heads?
3. Someone mentioned that Replacing non-PI with PI increases compression to over 10:1, Would this be an issue with running 87 octane gas? (I have to run regular because I dont pay for it and that is what they tell me I have to run)
4. How about these? Would these be a direct replacement, and do they have the added threads to hold the plug in place?
http://cgi.ebay.com/ebaymotors/Ford-...spagenameZWDVW
Thanks in advance to anyone who takes the time to address my concerns without flaming me off the site. I have honestly done numerous hours of "SEARCH", looking at pics, emailing, etc. These are just concerns on my specific application. i will be sure to take pics and post up once I tackle this project to contribute to this wonderful site. Thanks again!!
***LET ME KNOW IF THERE IS ANY INFO I LEFT OUT THAT WOULD BE HELPFUL IN HELPING ME UNDERSTAND*****
1. I have a 99 F150 5.4L, Does my truck have PI heads or non-PI heads, and do PI heads have more threads than non PI heads?
2. Is there a difference between the upper/lower intake on PI heads vs. non PI heads?
3. Someone mentioned that Replacing non-PI with PI increases compression to over 10:1, Would this be an issue with running 87 octane gas? (I have to run regular because I dont pay for it and that is what they tell me I have to run)
4. How about these? Would these be a direct replacement, and do they have the added threads to hold the plug in place?
http://cgi.ebay.com/ebaymotors/Ford-...spagenameZWDVW
Thanks in advance to anyone who takes the time to address my concerns without flaming me off the site. I have honestly done numerous hours of "SEARCH", looking at pics, emailing, etc. These are just concerns on my specific application. i will be sure to take pics and post up once I tackle this project to contribute to this wonderful site. Thanks again!!
***LET ME KNOW IF THERE IS ANY INFO I LEFT OUT THAT WOULD BE HELPFUL IN HELPING ME UNDERSTAND*****
Senior Member
Joined: Jun 2004
Posts: 144
Likes: 0
From: Aberdeen MD
Yes your truck has PI heads.
Those heads are the windsor heads same as whats on your truck now. Which means unless they put time certs or re thread the spark plug holes the plug blow out issues still exist. Find out if those heads have only 4 threads for holding the spark plugs in. If so i don't think they are worth it. If I ever blow a plug I'm gonna just gonna change my heads over to the Romeo type.
Those heads are the windsor heads same as whats on your truck now. Which means unless they put time certs or re thread the spark plug holes the plug blow out issues still exist. Find out if those heads have only 4 threads for holding the spark plugs in. If so i don't think they are worth it. If I ever blow a plug I'm gonna just gonna change my heads over to the Romeo type.
Technical Article Contributor
Joined: Dec 1997
Posts: 9,417
Likes: 11
From: Windsor,Ontario,Canada
RpSS4844,
1. I have a 99 F150 5.4L, Does my truck have PI heads or non-PI heads, and do PI heads have more threads than non PI heads? For the 2003 Model year Ford changed the design of the PI head and increased the number of spark plug threads to 8. Anything before that will have 4 threads.
2. Is there a difference between the upper/lower intake on PI heads vs. non PI heads? The shape of the runners at the flange where they bolt on to the heads on the non PI's are teardrop shaped where the PI are more of an parallelogram. 1999 5.4s had aluminum upper intake manifolds. 2000+ went to plastic.
3. Someone mentioned that Replacing non-PI with PI increases compression to over 10:1, Would this be an issue with running 87 octane gas? (I have to run regular because I dont pay for it and that is what they tell me I have to run) You could run into problems using such a low octane gas. I would use at least 91.
4. How about these? Would these be a direct replacement, and do they have the added threads to hold the plug in place?
http://cgi.ebay.com/ebaymotors/Ford-...spagenameZWDVW Save your money and by a time cert; http://www.timesert.com/html/triton_repair.html or a Lisle kit http://www.sjdiscounttools.com/lis65900.html and fix it yourself.
Regards
JMC
1. I have a 99 F150 5.4L, Does my truck have PI heads or non-PI heads, and do PI heads have more threads than non PI heads? For the 2003 Model year Ford changed the design of the PI head and increased the number of spark plug threads to 8. Anything before that will have 4 threads.
2. Is there a difference between the upper/lower intake on PI heads vs. non PI heads? The shape of the runners at the flange where they bolt on to the heads on the non PI's are teardrop shaped where the PI are more of an parallelogram. 1999 5.4s had aluminum upper intake manifolds. 2000+ went to plastic.
3. Someone mentioned that Replacing non-PI with PI increases compression to over 10:1, Would this be an issue with running 87 octane gas? (I have to run regular because I dont pay for it and that is what they tell me I have to run) You could run into problems using such a low octane gas. I would use at least 91.
4. How about these? Would these be a direct replacement, and do they have the added threads to hold the plug in place?
http://cgi.ebay.com/ebaymotors/Ford-...spagenameZWDVW Save your money and by a time cert; http://www.timesert.com/html/triton_repair.html or a Lisle kit http://www.sjdiscounttools.com/lis65900.html and fix it yourself.
Regards
JMC