This must be the best bang for the buck mod for Non-PI cars

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Pi heads are on 99+ 4.6 2v engines. Before that are NPI. PI , is power improved.they flow a little better. the ports are a little differnet from NPI heads. That is why most that do a PI headswap, purchase a 99 + intake.
 
WHAT?! so i can use my PI intake manifold on my non PI heads and get 25 hp?! this cant seem right. this would be perfect anyway because my stock intake is leaking coolant around the sensors! I NEED INFO!!!!
 
That 25hp was up towards redline. Peak hp gain was 15hp. It gained no tq peak to peak, but look at the gains farther towards redline. Crazy numbers for $100.

I put a write up on www.modulardepot.com in the 2V section. Go print that puppy out, and throw the PI on that car. You are gonna crap your pants when you feel the difference.
 
ARE YOU REALLY SERIOUS ABOUT THIS?! if so, i'm doing this as soon as it gets somewhat warmer. how long did it take you to swap?

im still curious about where you put the other coolant temp sensor. can u give a little more information on this? thank!!!!!!!!!!!!!!!!!
 
Took me about 5hrs total. This was messin with stuff that I wasn't sure how I should tackle. Like the dumb EGR in the way, etc.

The other coolant sensor is in the side of the block. There is a little plug, you cant miss it if you were to look. It threads out, a bunch of coolant will dump out, then put in the sensor in that hole. Extend the wires to the sensor, and you're done.
 
Makes you wonder how much power actually comes from the "heads". Seems that about 25-35hp comes from the intake and cams. That would leave about 25 for the heads themselves. I picked up 70 hp but my heads were ported and polished. Great thread!!!!!
 
fastang96 said:
Makes you wonder how much power actually comes from the "heads". Seems that about 25-35hp comes from the intake and cams. That would leave about 25 for the heads themselves. I picked up 70 hp but my heads were ported and polished. Great thread!!!!!

He just has the NPI cams and look at those numbers! Especially after the old intake ran out and the new one kept going. If he gets that a/f fixed he will be in hog heaven. There is more there with just the intake, but I bet you could see another 10-15 out of it if you added in the cams.
Some people who know a lot about this think the heads alone really aren't worth much if anything. The PI headswap will up your compression and you will definitely get a boost from that though. The initial investment and bang for the buck factor is really attractive for this route and with just the intake and cams you don't need to run premium all the time.
I have a pretty much stock 98 GT that I had on the dyno a few months ago to get a baseline. Nothing else has changed and I will be putting the PI intake and cams in mine first. It will be a few weeks for me and someone will probably beat me to it, but I will let everyone know what the new numbers are after I am done. I bet someone will already be there this weekend if not the next few days.
I love your attitude too man. Says a lot about you. You know what you have and I am sure it was worth it to you. A lot of people are naysaying because they spent the big bucks like you did and I think they are trying to feel better about it. I have been reading a lot of stuff about how you don't want your ports mismatched and you will "blow" those gaskets out. blah, blah, blah... :bs:
If these people saw some of the stuff we worked with on the early "musclecars" it would blow their minds. I have taken factory intakes off of cars that had as much if not more mismatch.
Bottom line, if it works, it works. The numbers don't lie. For those who want to take their time and do it right the reward is there. You won't be blowing anything out unless you put it together wrong and didn't get it sealed right in the first place or if you use forced induction.
Kudos to those who were not afraid to try something new. :hail2: