I just wanted to thank everyone here for the excellent information! Nice write up Patman0911, lots of information I have been hunting everywhere for! I was driving my '96 GT to school after having just gotten it out of storage for the winter. When I got there, I blew my head gasket in the parking lot. I thought this was the perfect opportunity to do the pi head swap, so I got myself a set of pi heads and intake off a 2001, as well as the coolant nipple and pi coolant tube, and (thanks to your post clearing this up), an alternator bracket. I love my Mustang and can't wait to drive it after this swap. Thanks again for a good write up!
Good luck! Should be a really nice increase in power with the full PI swap. Glad you found the info helpful.
I don't know if I added anything new - most of it's out there somewhere and been around for a while, but I tried to collect as much as I could into one place because you have to do a lot of cross-referencing of all the various writeups because they all gloss over one aspect or another or take for granted that you already know all the ins and outs of the various year differences in these motors.
you dont have to tap the pi intake if you get the romeo one for the 96-98 do you?? thats only for the windsor right
I don't think there's such a thing as a Windsor or Romeo PI intake (when talking about passenger car intakes), there's just the early all-plastic PI intakes and the later aluminum crossover PI intakes - they updated the intakes after passenger car engine production resumed at the Romeo plant so some Romeos have the all-plastic intake.
All PI intakes have only one coolant sensor hole tapped and all NPI require two coolant sensors so you have to deal with it one way or another with either style PI intake or give up the your temp gauge.
The all-plastic intakes only have provisions for one coolant sensor so you either have to find a location to tap on the head or block, tap the t-stat housing (gauge may not read accurately when the t-stat is closed - also not much metal to work with so it probably needs reinforcement) or run a tee for both sensors in the crossover (not a very good solution as it's almost impossible to get good readings like that - see the thread about coolant boiling over in tech currently - and both your gauge and the PCM will get bad readings possibly affecting driveabilty and MPG)
The aluminum crossover intakes already have a spot for a second sensor in the correct location but it needs to be drilled out and tapped, or, you can swap the crossover tube from an updated aluminum crossover NPI intake which already has that hole tapped.
The two coolant sensors operate in different electrical ranges so you can't just splice the wires together and make it work. There is a GM dual coolant sensor that could possibly be made to work if the ranges could be corrected to fit what the PCM and dash gauge expects to see, maybe just some simple resistor circuits would work - I started to look at that once but then the aluminum crossover PI intakes started to become widely available and reasonably priced and there didn't seem to be any more need for a complicated solution to a simple problem.
If you're doing this swap and have the all-plastic PI intake, I recommend selling or giving it to to someone with a PI car that needs an intake and getting the aluminum crossover PI intake instead - it's really just much simpler and you won't have any issues to worry about with the cooling system monitoring since everything is in the correct factory location and functioning as intended - you'll have enough to worry about with wondering if you put everything back together right and leak free without also having to worry if the temperature readings are right or are you actually overheating but the gauge is reading low...
