96-98 vs. 99-04?

5spd GT said:
So what else does the Dorman Intake have besides tapped holes for sensor? More cfm? More cross sectional flow?

Why does the PI cam's differ $50 bucks? Where do you find them at?

LI98GTstang - They seem to be about 20-25rwhp higher with those mods.

The Dormans are factory spec replacements for the 99+

As for the cams, look at the classifieds in the forums here and @ MPH and modular depot. There are alway PI cams for sale.
 
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I already have 4.10's and a king cobra clutch with a shorty shifter. I also have 2 1/2 inch X-pipe with 2 1/2 catback and 3 1/2 inch ss tips. I also have a fenderwall intake and summit racing plugs wires. Can someone estimate what I might run on the track with street tires in the 1/4 mile? I was thinkin I might be putting down 210 rwhp tops with my mods. It does pull really hard though through first and second:D Would pullies make it pull alot more?
 
billfisher said:
get the MMFF articles called RED HEADED step child. it's an excellent chronicle of low power from even ported NPI. now if you get frpp heads npi it's a different story.

do a little research. put PI's on npi like i did, and you will outppower 99+ mod for mod. enjoy it.

MM&FF is not even good for toilet paper, I wish that sad excuse for a magazine would just stop printing and disappear. All it is ever full of is how great their sponsors stuff works. I don't think I have ever read one of their mags that was not full of errors. When a Mustang doesn't win an FFW event, the winner gets slammed or not even mentioned. I could really care less about what that mag says works and doesn't because they at MM&FF do not have a clue.
 
For anyone wanting to know. The PI motors have more of a dished piston than the NPI motors do. Also the chamber on the head is slightly smaller, so that keeps the displacement the same on the updated PI motor. So when you add a smaller combustion chamber head(PI) to a less dished or flat piston(NPI), the compression raises, in turn increasing Power and Torque. Now from what I understand it only adds 10 -15 horses. i don't think it's worth messing with for that little of power gained. I have looked into this many times, many different searches on here and thats what i came up with.
 
01Steeda said:
and ramprat I am not bashing your car. you have done a great job with it, and I always tell my wife how much I like it. but be serious. you had more mods than I had when you ran those numbers. All I had was flowmasters and underdrives. you had CAI, plenum, Tb, prochamber, exhaust and a tune. I dont wanna put down on your car. your making guys around here look again,.. but be honest. a pi intake and cams wont make the same power as a pi headed motor with the exact mods.
Now Spike...what numbers are you talking about? You know that the dyno day we went to isn't a fair comparison. Jay admitted his dyno was off that day so results were skewed from car to car. The only real comparison would have been runs on the same day if you are comparing my numbers now. My car has a conservative tune due to the high mileage maybe good for only another 5-7 HP. Technically you are correct...you can talk flow rates and all BUT we are only looking at a few HP...less than 10 more than likely. IF you buy everything new I still come out cheaper buying beefier cams and intake over a headswap...and I make the same power. It's been stated that a PI car puts 230 to the wheels stock...my car is argueably at 245 in Dynojet numbers. Take into account you add a TB/Plenum to the PI car you will gain 4-6HP. Midpipe is good for another 10. Add to that 4.10's that sap some HP and your PI car is right at the same HP. Now add a small cam to the PI car such as the Comp 262 like I have and you may be 10HP-15HP over my car. I just feel a headswap is a waste of time and money for 10HP...
 
5spd GT said:
So what else does the Dorman Intake have besides tapped holes for sensor? More cfm? More cross sectional flow?

Why does the PI cam's differ $50 bucks? Where do you find them at?

LI98GTstang - They seem to be about 20-25rwhp higher with those mods.

So catted x-pipe and pulleys are worth ~20-25rwhp? I posted my dyno chart as to proof of what mods were worth on my stang, so let's see some dynos of just those mods in the 255rwhp range on 99+. This would be eye opening for me, so I'll keep and open mind here. I was just going by what I've seen on the place I went to get dyno'd by way of recollection.
 
Gearbanger 101 said:
Another :nice: for the use of Non-PI heads. I went with a PI head swap with my engine, but that's only because my Non-PI heads were damaged when the previous owner squeaked it. Had they not been, I would have ported them and just dressed them up with PI cams and valves.

I went with another set of PI heads mainly because of their cost. For what I paid for my PI heads, I couldn't have bought another set of NPI's and later model cams and valves for the same price.

When I'm done with this car, I'm pulling the whole powertrain out and dropping it into a '96-'98 Mustang. Love that body style. :nice:
The truth speaks...:nice:
COramprat congrats great numbers! You got the PI guys panties in a twist lol.
 
Stock 99-'03 GTs with 5sp. that I've personally seen bone stock on the same dyno have been right around that number. With similiar mods as mine with essentially the only difference being the PI heads themselves, have been in the approx. 10-15rwhp above


exactly what i am saying.. it may only seem like 10-15hp.. but when you think about the guys spending 200 bucks on a CAI that wont give you 2hp, then a set of used PI heads for 200-300 dollars that will gain 10-15 is quite a bargin.

calm down guys. we have different views. this is america right. 10-15hp to u is "the same HP" to me it is a tenth or better in the 1/4.:SNSign:
 
Outlaw97GT said:
PI cams- 100.00 New
PI Intake- 200.00 New
-------------------- = 300.00

PI heads swap - 1350.00 New

So your spending 1050.00 for 10HP!
Im planning on getting the comp 268H cams and a PI intake.
268H - 550.00
PI Intake - 200.00
So for 750.00, I will make more power than a head swapped car. And my compression won't be to high for a S/C in the future.

Come on now Bro,
I have seen guys all over the net selling the entire PI packages (heads,cams,intake) for around $300. Some wreck their Stangs and take the motor out, some swap in 3 or 4 valve motors, there are a lot of PI packages out there going for less than $400 and some little mileage on them. $1050 for 10HP is a little far fetched.

But I'm still having a hard time believing why you would port or keep NPI heads when PI heads have way more potential...:shrug:
If the NPI heads are so good, then why doesn't Fox Lake or Patriot Performance sell ported NPI heads? They don't, they sell the ported PI heads. Ported NPI heads may flow well, but they are still limited. The PI vs NPI package likens to a 87-93 head,intake,cam package vs a 93 Cobra head,intake,cam package. Of course you can port the 87-93 heads and intake, but the Cobra intake & GT40 heads have way more potential..:nice:

But even a Cobra intake has its limits. Of course a ported Cobra intake flows up there with Edelbrock,TFS, and Holley, but it has to be ported, whereas the other ones are out of the box stock. Now port those bad boys, and it's Whoaaaa Nelly. Bottom line is, "If you're gonna upgrade, upgrade." You wouldn't drop in a 700HP motor and upgrade the fuel system and then leave on 19lb fuel injectors, or keep the stock cooling system, or keep stock ignition system.

Trust me, Ford tries to save every penny they can. If they thought the only thing choking perfomance was the intake, they would've only made an intake upgrade and kept the NPI heads and saved millions and millions of dollars because designing a new head isn't cheap, but they didn't. They upgraded the heads also because they knew the PI heads had more potential than the NPI heads...:D
 
lover said:
Come on now Bro,
I have seen guys all over the net selling the entire PI packages (heads,cams,intake) for around $300. Some wreck their Stangs and take the motor out, some swap in 3 or 4 valve motors, there are a lot of PI packages out there going for less than $400 and some little mileage on them. $1050 for 10HP is a little far fetched.

But I'm still having a hard time believing why you would port or keep NPI heads when PI heads have way more potential...:shrug:
If the NPI heads are so good, then why doesn't Fox Lake or Patriot Performance sell ported NPI heads? They don't, they sell the ported PI heads. Ported NPI heads may flow well, but they are still limited. The PI vs NPI package likens to a 87-93 head,intake,cam package vs a 93 Cobra head,intake,cam package. Of course you can port the 87-93 heads and intake, but the Cobra intake & GT40 heads have way more potential..:nice:

But even a Cobra intake has its limits. Of course a ported Cobra intake flows up there with Edelbrock,TFS, and Holley, but it has to be ported, whereas the other ones are out of the box stock. Now port those bad boys, and it's Whoaaaa Nelly. Bottom line is, "If you're gonna upgrade, upgrade." You wouldn't drop in a 700HP motor and upgrade the fuel system and then leave on 19lb fuel injectors, or keep the stock cooling system, or keep stock ignition system.

Trust me, Ford tries to save every penny they can. If they thought the only thing choking perfomance was the intake, they would've only made an intake upgrade and kept the NPI heads and saved millions and millions of dollars because designing a new head isn't cheap, but they didn't. They upgraded the heads also because they knew the PI heads had more potential than the NPI heads...:D


The best 2V heads are the SVO/FRPP heads, they are based off of the NPI head. Fox Lake Ported PI heads flow what, 220 CFM on the intake side, well my ported NPI's are flowing just over 230 CFM on the intake side. My NPI's still have the swirl dam, for the PI porters out there, to match that have to remove the swirl dams. If I wanted the swirl dams removed, I would have used my SVO heads, which ported will far outflow even the best flowing PI heads.
 
I'm not saying that NPI heads are better...or can even be made better than the PI's I'm just saying there are other options to the headswap on a NPI motor. If you can find PI heads and cams for 300...go for it. But don't be surprised when my NPI car gets you in the 1/4. :D
 
lover said:
But I'm still having a hard time believing why you would port or keep NPI heads when PI heads have way more potential...:shrug:
If the NPI heads are so good, then why doesn't Fox Lake or Patriot Performance sell ported NPI heads? They don't, they sell the ported PI heads. Ported NPI heads may flow well, but they are still limited. The PI vs NPI package likens to a 87-93 head,intake,cam package vs a 93 Cobra head,intake,cam package. Of course you can port the 87-93 heads and intake, but the Cobra intake & GT40 heads have way more potential..:nice:
Actually, TGL is right. The Non-PI's from what I've seen do flow better than the PI when both sets have been ported. So if you really want to get down to it, the Non-PI's are the castings with more potential.

You don't see Fox Lake and Patriot performance advertising port jobs for Non-PI heads because they're in the business of making money. Mustang owners have been brainwashed over the last 10-years to believe the pre-PI castings were good for nothing more than door stops and nobody wanted them. (trust me….the T-Bird/Cougar/Crown Vic guys figured this out long ago and are laughing all the way to the bank when a ’96-’98 Mustang owner sells a set of their “junk” heads to them for next to nothing) It didn't matter if in reality the pre-PI's could be made to perform really well for very little money, and even outperform PI's with the same modifications. People have been conditioned to see them as junk, so why would a company take a chance on trying to market the earlier “taboo” heads, when Ford had already endured the cost and expense of marketing the new PI castings for them. All they had to do was basically sell their CNC program….the heads sold themselves. Mustang enthusiasts wanted PI heads and that's what they got. True performance potential had very little to do with it.

As far as why Ford decided to change the heads in the first place. These heads were originally slated for use on the '99-up 5.4L in the F150. In bone stock trim, the new PI castings did show slightly better flow velocity at low lift levels mainly due to the restructuring of the emissions mask. Combining this with better valves and slightly more aggressive cams meant it would maintain good low-end torque and fuel efficiency, while increasing still being able to breath on the high end. Combine that with the fact that the truck now had a new matching intake manifold that sported longer and large volume square port runners to improve breathing capability on top of this and horsepower, torque and over all efficiency jumped dramatically. You’ve got to remember, the best selling vehicle in Fords inventory was and still is the F-series Pick-up and make no mistake…..it go the attention it needed first, long before the Mustang. Since these were in fact “Modular Engines” and the new head/intake package had already worked for the F150, why couldn’t it work for the Mustang as well? The Windsor plants were already set up for the new castings. A better breathing package is where the Mustangs 4.6L suffered, so why not swap out the Trucks Heads/Cams/Valve Train over to the Mustang for the same results. It was nothing for them to redesign and replace the old upper intake with a large volume long runner one….and since that’s where the 4.6L in the Mustang really needed the attention; they were likely to do it anyway. You see it as them spending millions of dollars for no reason; I see it as them killing two problematic birds with one stone and saving face and money at the same time.

lover said:
Trust me, Ford tries to save every penny they can. If they thought the only thing choking perfomance was the intake, they would've only made an intake upgrade and kept the NPI heads and saved millions and millions of dollars because designing a new head isn't cheap, but they didn't. They upgraded the heads also because they knew the PI heads had more potential than the NPI heads...:D
Believe it or not, it's not always about saving money with Ford. They'd already had problems with the '99 Cobra's being down on power and they were damned if they were going to lose any more GT sales to the Bow Tie camp because of the lack luster performance associated with the previous model GT. The cars ran just fine without the modifications, but keeping customers happy in the power department was their main concern. Ford spent a lot of money in the '99 model year between those two cars on what would be considered by bean counters standards an “unnecessary expense".
 
My car with no performance mods ran a 15.2@92 with a 2.1 60', stock. This run I did not spin at all.

Stock 04' engine,3.73's,I ran a 14.2@99 with a 2.1 60'. I spun through most of first, and shortshifted into second.

Same crappy launch and ok shifting, much different results. BTW the DA at was basically the same each time out.

I think the results speak for themselves
 
LI98GTStang said:
So catted x-pipe and pulleys are worth ~20-25rwhp? I posted my dyno chart as to proof of what mods were worth on my stang, so let's see some dynos of just those mods in the 255rwhp range on 99+. This would be eye opening for me, so I'll keep and open mind here. I was just going by what I've seen on the place I went to get dyno'd by way of recollection.

I'm talking about 20-25rwhp from heads. Not catted x-pipe and pulleys. Where are you reading?


Where are you getting the 255rwhp numbers? You dynoed at 229rwhp.
 
5spd GT said:
I'm talking about 20-25rwhp from heads. Not catted x-pipe and pulleys. Where are you reading?


Where are you getting the 255rwhp numbers? You dynoed at 229rwhp.

Yes, I dyno'd at 229 with PI cams and intake plus I had catted X and pulleys at the time, and you asked for someone with 230rwhp without the fullheadswap - PI intake and cams only and I responded. If you or someone could post a 99+ stang with those same two mods then we can directly compare with the heads being the only difference.

The 255 came from your estimate that the heads themselves are worth 20-25rwhp on top of stock stock 99+ PI headed stang being approx. 230rwhp (230+25=255). The 99-04s that I've see with similiar mods as mine were in the low 240 range which would mean that the heads are worth ~10-15rwhp.