would 5.4 heads work on a 4.6 i just thought bout it. it might be a dumb question i don't know if they would work or not just curious. also would these then be better then pi 4.6 heads if they work?
Really I would have though that they would have larger ports but I'm not very familiar with the 2v 5.4 heads. I do know that the later 32v heads used on Navigators while very similar to 03/04 4.6 32v heads have larger ports because of the increased displacement of the 5.4. I am pretty sure the 99-02 5.4 32v heads most likely have larger ports as well but don't qoute me on it. If your looking for 32v then don't stick em on a 4.6 then might do ok on a stroker or bigbore though. After all the FR500c race cars rune the larger port Ford GT style heads on a BB but again this engines are most likely sluggish at low rpms but scream in uppers where then need all that extra air.
That definitely explains why the 2v 5.4 run out of power real low in the rpm range, well that and the mediocre flowof the PI’s they’re OK for a 4.6 but just don’t cut it on a 5.4. Thanks for the clarification.the 2V PI heads (romeo and windsors) are pretty much like a '1 size fits all' deal that were used on both 4.6s and 5.4s....you're right in that the navigator (5.4) heads have much bigger intake ports compared to 4.6 tumble-port heads....so the DOHC vehicles did indeed get a more vehicle-specific head designation
Yea tell me about it I've been saying for years Ford should have gone with a 3.7 inch bore from the start but no they wanted to mount these things transversely for FWDR applications so they had to limit their freaking bore spacing. Wow look how that ended up Lincoln Continental oh wait they haven’t made that thing in years. They really should have worked a little harder on the 2v’s think about it PI heads don’t even match GT40’s in flow plus the valves have a crapper shot at the combustion camber because of shrouding. The worst part is even the 3v's aren't good enough on a 5.4 the only way to go with them is the 32v's.actually it's not even that....the valves are too close to the outer edges of the combustion chamber/cylinder walls.....this is called valve-shrouding.......neither PIs nor NPIs are adequate for a 4.6, let alone a 5.4........this is why there are huge gains when people go with 3.7" big-bores in aluminum blocks with PIs or NPIs
I don't know that's a pretty far drive for me across the ENTIRE Delaware river and all lol. I work alternative Saturdays so I'll have to see which one it falls on but I love car shows and definitely would like to see your 5.4 set up.My stock 5.4L crank/ rods can rev just as high as a stock 4.6L crank/ rods. In fact my peak HP ends up close to the same RPM (4,700 to 5,000) as an equal 4.6L. I doubt that there will be much of a difference if you add better heads (that I can not afford) with 4.6L cams.
Not until you add a set of cams that are designed to take advantage of the clearance between the pistons and the valves on the 5.4L to some high flow heads would there be a difference. This is one of the trick$ the big boy$ use.
PS: You should come to our car show in Morrisville April 25th. I will show you my 5.4L!