I hava 98 F-150 with non PI heads. My question is has any body changed out the non PI heads for PI heads. If this has already been discussed please provide a link.

 

I know I've heard it discussed before but I don't recall where.... anyhow, I plan on doing it to my 98. I want to use patriot stage III heads... I already have my Comp Cams for the job, along with my ARP head studs. The intake however I'm finding to be a bit of an issue... It appears that I might have to buy new because I can't find I used PI intake. New for upper and lower is about $500... on top of the $1500 for the heads.... then the gaskets... it's going to add up... I'm buying everything part by part. Also I'm going to run 24lb injectors because of the cams, custom tuning that I'll have done by Pauls High Performance (Jackson, MI) and the mods I've already done (MSD coil packs, K&N FIPK, Granitelli mass air meter, 70mm throttle body, ported intake elbow, JBA ceramic coated stainless headers, full stainless steel true dual exhaust from headers back, and eventually it will get MSD DIS-4 ignition).

 

ahhhh I didn't read what you already have on your truck... You'll still face the problems with the intake that I've got... and depending what size injectors you're running right now, you might have to step up on those too; were you planning on factory PI heads or some CNC ported/polished heads?

 

Here you go:
https://www.f150online.com/forums/sh...hreadid=177065

 

I forgot to mention, you will want to try to get the intake manifold as well, if not, it would be a good idea to port match the ports on the manifold to the new heads (they are not the same shape).

 

Thanks Johngs

 

Are the heads and intake the only major difference between 97-98 5.4l and 99-03 5.4l.

 

To answer your answer your question Nate I plan on buying factory heads and have them ported and polished as well as the intake at a local machine shop. I will just buy one thing at a time and take my time finding the parts I am in no hurry. Right now I am in the process of tweeking my supercharger. By the time I find the parts I might just go ahead and rebuild the motor and do it all at once.

 

Pretty much yeah. Although if you can get '03 heads, you would get 8 threads for the spark plug holes instead of just 4. If you cant get the newer heads, consider installing inserts before you install the heads.

 

Are you talking about the time-certs

 

Yes. Some of these engines tend to spit out spark plugs, the 4 threads isnt really enough to keep the plugs in.
Since you are running a supercharger, it would be a good idea since the problem seems to be worse in boost applications.

 

NateRW21,

The 4.6 didn't get PI heads till 01. If you try to fit that model year intake on your engine it will fit but it has no provision for the 2 coolant temp sensors that your harness has.

JMC

 

I keep forgetting he has the 4.6...
Wont he also have to make sure he gets the right heads (romeo vs windsor)?

 

We are getting of track here I have a 5.4 L. All 5.4L are Windsor except for the DOHC Navigator 5.4L, Lightning and Harley Motors they wrere built at the Romeo plant.

 

It doesn't matter if he gets windsor or romeo heads. They will both bolt up. Windsor heads require different valve covers and the windsor heads are the ones with the plug blow out issues.

I don't know about the dohc 5.4L but the lightning and harley engines were built in the windsor plant