i have a 97 4.6 that has been threw hell and back. now i want to upgrade the heads to PI Heads and i am stuck. I dont know what intake manifold would it use. anybody know if i could put PI 4.6 heads with a 01 4.6 intake manifold.

 

i believe 99+ is PI, thus even if the intake was different the 01 intake should work with the PI heads.

but some reason i think the intake manifold should still bolt up?

 

no it wont seal up, you have to have the PI manifold. I have a 2 page writeup if you want it.

 

well i covered my base! i said even if it was different the 01's intake would be PI.

sorry, my bad i didnt realize they wouldnt seal up.

 

Built

Correct me if I'm wrong. But don't all F150 4.6s from 1999 and up have PI heads? Hence they have PI Intake and Exhaust manifolds.

I also think that in '99 the intake went plastic with a aluminum cross over in front for the coolant. I know the '04 is all aluminum again, not sure if that switch was made earlier than that or just for the new body style.

Doug

 

Yeah, any PI manifold will work on the PI heads. 99 and up

 

Hey, Built

I have been thinking of doing a head swap on my truck. Could you tell a differance in power after the swap.

 

The 4.6 got the Pi heads in 01. Ford switched to plastic when they changed the intake. So if you have a metal intake for a 4.6 it is not a PI intake. Just look at the shape of the runner ports. Tear drop is Non Pi.

JMC

 

with comp cams #102500, I gained 100hp from 3k up

 

holy s--t,

I had know idea the swap with cams would yield that much Horse Power. What is your H P at the fly wheel. The only problem I see with the head swap in my situation is the compression because I'm supercharged. I wonder if the PI heads could be ported enough with the use of a supercharger.

 

JASON'S98S/C4X4,

The only effective way to lower the CR is to change the pistons out for deeper dish ones. You could send your non Pi heads out to get them CNC'd. I would not risk trying to enlarge Pi head's combustion chamber.

JMC

 

didnt know you were supercharged, I wouldnt do it then, boost would have to be low along with timing, unless you want to run race gas...

 

You could say its 325hp at the flywheel. that dyno run was with my heavy tires...

 

hey built, i am confused i need to know what kind of intake i need to swap some pi heads on my 97 4.6 and where i could find it. or what kind of upgrade i should do with 2500$. my truck has about 143000 miles and i already have exhaust, headers, hi flow cats, programmer, high output ignition system, 4.10 gears. any opinions would help. hey built i also been looking at some turbo by sts all that sounds good, so like i said im confused. thanks

 

Try these heads, they are a bit expensive but they out flow the p.i.'s and you don't have to buy any other parts for the swap..

M-6049-D46 Ford racing part number.