So i opened up the maintence manual for my car today, and i saw the last owner wrote everything down, and i stumbled across something that caught my eye.. the entire intake manifold was replaced at 30,000 miles in june of 1999, and so i started wondering..do i have a pi head? I took a pic of the aluminum cross over, and i had heard that that's a way to tell. is this true?



sorry if this is kind of a stupid question, i just never knew how to tell the difference haha

 

You can install a PI intake on NPI heads... so that doesn't mean much.

 

I'm pretty sure my car has an NPI intake with an aluminum crossover. So you may not even have a PI intake.

 

I shouldve worded the thread better..i shoulda asked do i have a PI intake manifold

 

Your engine probably still has the original heads. It's just the intakes on the earlier 4.6 engines had problems CRACKING and leaking anti-freeze. That's why there is aluminum where the coolant crosses over, instead of plastic. But you do have the UPGRADED Intake though.

 

It's hard to tell from you picture but I have a picture of my PI intake and NPI side by side.



Do you see how the NPI intake (the one on the left) has a threaded hole on the coolant cross over above the thermostat housing? That is because the NPI intake has 2 coolant sensors/senders and the PI intake only has one (which is on the passenger side of the coolant passage.

 

The aluminum crossover needed when doing a PI swap is under the lower intake. You can't see it unless other intake manifold is off. It runs from the back of the water pump to I believe the head.