Truth about NPI vs PI

Isn't 400 supposed to be the number that gets stock internals grenading out of the block?

Oh I know all about popping spark plugs. I lost #8 a few years back and had the guys from blownoutsparkplug.com fix the head. In retrospect I should have done the PI swap then but I hated the car at that point.

So, if I purchase a set of heads I should ask if they are the later, revised heads? Are the brand new Ford Racing heads from vendors like Modular Mustang Racing or Blue Oval Chips the revised heads? I wish I could buy the Trick Flow stuff but I just can't swing it.

Question: since I live in Commie-fornia I have to be smog compliant. Does anyone know how this PI stuff will affect my emissions?

 

400rwhp forced induced makes it a bomb. N/A is ok, but detanation destroys anything.

I do not know the 04-up head part #'s, but definitely ask if purchasing new ford pi heads like the ones listed in Summit/Jegs.

Keep the cats and get her tuned, should be fine.

 

If your FI you have to worry about eating plug bosses too

 

I couldn't handle FI; a PI car will be fine. I'm just trying to put together the SN95 GT that Ford should've built...

 

Alright so I found someone locally that has new PI heads and cams for sale. The only question I have for the seller is whether these are Romeo heads, and whether they are the newer head castings with the increased spark plug thread count; I don't ever want to deal with the popping plug thing again. Is there anything else I need to ask? Something to look for? I've never bought anything as involved as a cylinder head so I'm clueless. The heads are supposed to be assembled and ready to go. Any input or suggestions are appreciated...

 

New heads...wow! Just look at the sparkplug holes to see if there are 4threads or 9threads.

 

Well, I guess if they're the older heads then I could have them time-sert'ed just in case.

Question: should I bother making a dyno pull to see a baseline BEFORE the PI install and tune or would that be a waste considering the nature of the non-PI motor anyway?

 

if you want to pay for the extra pull just to see what the difference is its up to you but it would be a waste of $$$ since it would all be old news once the new gear was installed.

 

You could send me a set of npi heads to work out for you! Yes im feeling generous, but you talk about dyno tuning and this is a great opportunity for others to see how well a set of worked npi heads perform.

 

quote of the day.

 

I figured he'd latch on...

 

I'm a SN95 newbie. I'm a cheap SOB and am not looking for megapower, just more than I have. My head is spinning from reading all the stickies on the 4.6 NPI to PI upgrade. I have a 98 GT and there is a complete 2006 Crown Vic cop car motor I can get cheap. Does the Crown Vic come with the same higher lift cams that a Mustang would? Intake? If I have the entire 2006 engine, I would have all the parts I need to swap heads and intake except gaskets, correct? I also see a set of 2005 Mustang 3V heads. Would they work?

Thanks!

 

It was complete, owner said it had 120k miles and ran good, $200 with the slipping tranny, but sold it two weeks ago. Damn!