Did all 4.6L cars get P.I. heads in 1999?
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Cobra R Member
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From: Massachusetts
Did all 4.6L cars get P.I. heads in 1999?
I have debated doing a P.I. swap for my 1997 GT and I found a set of heads from a 2001 Town car. Are these heads identical to the 1999-04 GT? What else would I need besides the heads, intake, gaskets etc.
I can get these heads for $150, is that a good deal should I be suspicious?
I can get these heads for $150, is that a good deal should I be suspicious?
Tasca Super Boss 429 Member
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From: Midlothian, Va
Its hard to say. I've seen some places that say yes and some places that say the tc didn't get pi until 04. I would say go look at it and check the casting number. If it starts with RF-F5AE then its NPI. If its starts with either RFXL3 or RF1L2E then its a PI head.
That doesn't sound like a bad deal at all. Typically they are cheaper then the Mustang heads. I don't know hp numbers between the 2 so I don't know how they compare.
That doesn't sound like a bad deal at all. Typically they are cheaper then the Mustang heads. I don't know hp numbers between the 2 so I don't know how they compare.
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From: Massachusetts
Thanks for the heads up I'll double check the casting before I pull the trigger. I thought the engines were identical with the exception on the intake, anything I should worry about? I wonder if I should just get heads from a mustang instead
Tasca Super Boss 429 Member
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From: Midlothian, Va
Originally Posted by 97GT03SVT
Thanks for the heads up I'll double check the casting before I pull the trigger. I thought the engines were identical with the exception on the intake, anything I should worry about? I wonder if I should just get heads from a mustang instead
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Cobra R Member
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I have done some research and these should be pi heads. Its crazy to see how many variations of the 2V 4.6L were made. For example 99 expeditions had a pi Windsor, 00 were npi Romeo, and on 01 they were pi Romeo. Very strange!
Last edited by 97GT03SVT; Dec 23, 2012 at 02:51 PM.
Tasca Super Boss 429 Member
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From: Midlothian, Va
Originally Posted by 97GT03SVT
I have done some research and these should be pi heads. Its crazy to see how many variations of the 2V 4.6L were made. For example 99 expeditions had a pi Windsor, 00 were npi Romeo, and on 01 they were pi Romeo. Very strange!
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This may be the first step in a long process. I want to do this as affordable as possible, nothing crazy just the PI upgrade along with a tune. I hoping that should put me in 280HP territory.
I don't think it is worth buying a used intake though, unless its one from a bullitt.
I don't think it is worth buying a used intake though, unless its one from a bullitt.
Last edited by 97GT03SVT; Dec 23, 2012 at 03:47 PM.
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Going along with what 1999Pony stated here are some casting #'s that may help out.
F1AE/F2AE/F4AE & F5AE are non pi romeo heads '91 thru '95
F65E/F75 & F75E are windsor non pi's '96 thru '99
XL3E are windsor PI's '99 thru '01
1L2E/ 2L2E are romeo PI's '01 thru '04
2L1E are windsor PI's '02 +
F1AE/F2AE/F4AE & F5AE are non pi romeo heads '91 thru '95
F65E/F75 & F75E are windsor non pi's '96 thru '99
XL3E are windsor PI's '99 thru '01
1L2E/ 2L2E are romeo PI's '01 thru '04
2L1E are windsor PI's '02 +
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This may be the first step in a long process. I want to do this as affordable as possible, nothing crazy just the PI upgrade along with a tune. I hoping that should put me in 280HP territory.
I don't think it is worth buying a used intake though, unless its one from a bullitt.
I don't think it is worth buying a used intake though, unless its one from a bullitt.
When using PI heads on a NPI engine you're going to end up with a higher 10.5:1 compression ratio.
Windsor and Romeo PI heads for SOHC 2-valve engines flow identically, but have different valve cover and timing chain cover bolt patterns, and different cam gear attachment styles (pressed vs bolted). Windsor PI engines came in 1999-2000 Mustang GTs, and Romeo PI engines came in 2001-2004 Mustang GTs.
The easiest way to add PI heads to a NPI engine is to use Romeo PI heads on a Romeo block and Windsor PI heads on a Windsor block. You'll need to use the valve covers that were on the new heads if mixing heads & blocks. The Windsor and Romeo heads use different valve covers. Windsor Heads/Valve Covers has 13 (driver side) and 14 (passenger side) bolts, and Romeo has 11 bolts.
You'll have to use a PI intake in your new PI heads. The NPI intake will not work.
Also make sure you get the coolant tube that runs through the valley. The PI is larger and sits deeper in the valley. The NPI tube will interfere with placement of the intake. The NPI thermostat neck is not compatible with a PI intake, so get the PI thermostat neck. The NPI alternator and PI alternators use different mounts at the top. You can modify the stock bracket and drill it to fit the NPI alternator, or buy a PI alternator and use a PI bracket. Next is the coolant crossover tube. NPI cars have (2) temp sending units in the crossover tube on the intake. One is for the temperature gauge, the other is for the computer. You may need to drill and tap the PI intake to accept the second temp sensor. Second, the PI heads use 10 mm accessory bolts. The stock NPI bolts are 8mm. The easiest solution is to search a junk yard for a PI motor and salvage the bolts.
Windsor and Romeo PI heads for SOHC 2-valve engines flow identically, but have different valve cover and timing chain cover bolt patterns, and different cam gear attachment styles (pressed vs bolted). Windsor PI engines came in 1999-2000 Mustang GTs, and Romeo PI engines came in 2001-2004 Mustang GTs.
The easiest way to add PI heads to a NPI engine is to use Romeo PI heads on a Romeo block and Windsor PI heads on a Windsor block. You'll need to use the valve covers that were on the new heads if mixing heads & blocks. The Windsor and Romeo heads use different valve covers. Windsor Heads/Valve Covers has 13 (driver side) and 14 (passenger side) bolts, and Romeo has 11 bolts.
You'll have to use a PI intake in your new PI heads. The NPI intake will not work.
Also make sure you get the coolant tube that runs through the valley. The PI is larger and sits deeper in the valley. The NPI tube will interfere with placement of the intake. The NPI thermostat neck is not compatible with a PI intake, so get the PI thermostat neck. The NPI alternator and PI alternators use different mounts at the top. You can modify the stock bracket and drill it to fit the NPI alternator, or buy a PI alternator and use a PI bracket. Next is the coolant crossover tube. NPI cars have (2) temp sending units in the crossover tube on the intake. One is for the temperature gauge, the other is for the computer. You may need to drill and tap the PI intake to accept the second temp sensor. Second, the PI heads use 10 mm accessory bolts. The stock NPI bolts are 8mm. The easiest solution is to search a junk yard for a PI motor and salvage the bolts.
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From: Massachusetts
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Incomplete
P.I. Heads must have P.I. Intake to complete swap. The holes for the p.i. Heads are squared unlike the oval ones on the old ones.
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Welcome,
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Kc
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Thanks For Updating One of Our Legacy Posts. We Actually Like Updates on The Old Threads Unlike Some Sites Which Pitch a Fit About it. Just Be Advised to Notate You Are Aware of The Age of Post Like This One Which is 12 Years Since Last Post. Otherwise Somebody Will Point it it Out {But Kindly} Thinking You are Not Aware it is an Older Thread. That is Especially When Quoting a Member Who May or May Not Still Be Active.
I Do The Same At Times Updating Old Threads If I Have Some Relevant Info to Add. It's Always a Continuing Learning Process With Car Info. I Sometimes Use a Quote on an Older Post Simply To Answer The Question. No Prob!
These Days We are A Library of Information and We Are Always Looking To Add More Content!
Again Welcome & I Would Invite You To Go to Introductions and Post Some Pics of Your Stang & Give a Little Background if you Like!
https://themustangsource.com/forums/f650/
Kc
ADMIN
