96-98 vs. 99-04?

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

If you read the "WHOLE" post you will notice I said "NEW" not used low mileage. Apples to apples. You can get a used PI intake for 50.00.
 
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LI98GTStang said:
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.

Dyno's vary. I don't think you will find many in that range. I take average vs. average. Some 99+ bone stock 5spd's have hit 235-240rwhp. But then again, I take average.

I asked without the heads and all else being stock. Not your example. Just PI cams and PI intake, untouched.

To many variables for one to compare one used to the other and see the gains that just the heads give.

Add the head horsepower and the upped compression to get the 20-25rwhp. Not just flow.
 
5spd GT said:
Dyno's vary. I don't think you will find many in that range. I take average vs. average. Some 99+ bone stock 5spd's have hit 235-240rwhp. But then again, I take average.

I asked without the heads and all else being stock. Not your example. Just PI cams and PI intake, untouched.

To many variables for one to compare one used to the other and see the gains that just the heads give.

Add the head horsepower and the upped compression to get the 20-25rwhp. Not just flow.


by doing a PI headswap you gain @ 40-45rwhp
by doing the PI intake/cams you get 30-35rwhp and i've seen dyno's...
so the 10 hp gained by switching to PI heads isn't that impressive when you factor in the almost 1 point of compression bump.
 
COramprat said:
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


ok now lets get down to real world results, forget the dyno. lets talk 1/4 mile.

correct me rick if I am wrong here. I dont wanna post untrue info. your car up until the cams had CAI,TB,Plenum,prochamber, catback (brand??) and 4.10's correct?:shrug:

my car before my ported heads and cams had pullies, flowmaster weld in's, 3.73's and a tune. must add in i have a vert which weighs considerably more

My best on that setup at our same track was 13.66 @ 100.xx

from my understanding even with the new cams and a tune... plus stickies you have yet to reach that. I AM NOT DOGGING YOU RICK!!! PLEASE!!dont think that, just a discussion. All I can figure is the Heads must have helped :shrug:
 
01Steeda said:
ok now lets get down to real world results, forget the dyno. lets talk 1/4 mile.

correct me rick if I am wrong here. I dont wanna post untrue info. your car up until the cams had CAI,TB,Plenum,prochamber, catback (brand??) and 4.10's correct?:shrug:

my car before my ported heads and cams had pullies, flowmaster weld in's, 3.73's and a tune. must add in i have a vert which weighs considerably more

My best on that setup at our same track was 13.66 @ 100.xx

from my understanding even with the new cams and a tune... plus stickies you have yet to reach that. I AM NOT DOGGING YOU RICK!!! PLEASE!!dont think that, just a discussion. All I can figure is the Heads must have helped :shrug:


I posted my results after each mod...thought it was here but I guess not. Anyway...

Catback is stock...still

4.10s, Prochamber...untuned...14.7 @ 94

Upper intake combo (PI, Plenum and 70mmTB)...untuned...14.5 @ 97

Cams and tune 14.0 @ 99

DR's 13.8 @ 103

My MPH traps on street tires were close to yours...my ET was low because I drive my own car. :D

On stickies I trapped HIGHER than your car did before your new motor...still with the same crappy driver. So someway, somehow I was able to get a BETTER trap speed (twice) than you had.
 
Pennywise2 said:
What is the elevation where you live in Louisiana COramprat?
Because your times are good for your mods.
12 feet...:nice:

The night of the 13.8's it was mid 60's with 35% humidity. Pretty decent weather. With the corrected times I should be running 13.7...again...just a hair from my good ol buddies 13.66...
 
COramprat said:
12 feet...:nice:

The night of the 13.8's it was mid 60's with 35% humidity. Pretty decent weather. With the corrected times I should be running 13.7...again...just a hair from my good ol buddies 13.66...
That explains it! Again congrats on your times you must have the drive mod lol. :nice:
What year car and what mods does your friend have?
 
COramprat said:
I posted my results after each mod...thought it was here but I guess not. Anyway...

Catback is stock...still

4.10s, Prochamber...untuned...14.7 @ 94

Upper intake combo (PI, Plenum and 70mmTB)...untuned...14.5 @ 97

Cams and tune 14.0 @ 99

DR's 13.8 @ 103

My MPH traps on street tires were close to yours...my ET was low because I drive my own car. :D

On stickies I trapped HIGHER than your car did before your new motor...still with the same crappy driver. So someway, somehow I was able to get a BETTER trap speed (twice) than you had.


Yeah thats true I hadnt noticed you trapped so high... :nice: there is definatly more there. although my car would have benefited from some sticky tires as well and most probably trapped alot higher. I would think though with the weight difference and the mods you should have been ahead of me, IF the heads were not a big deal right? Thats my point. you shouldnt be running right with me, you should be outrunning me if the heads were a non issue.

I dunno I for one agree if porting is your aim then stick with the NPI's.. more there to work with. I have said this to you as well rick. If not, you can pick up a set of used PI heads for 300 dollars all day. it is a very effective 10-15 HP increase. thats all I am getting at. If people are willing to spend 200 for 1hp from a CAI then why is 300 to much to spend for 10-15? and yes the compression is raised almost 1 point... 9.5:1... whoopdey doo :rlaugh:
 
So PI cams will work in NPI heads??
When you swap the intake manifold there do you need to get it tuned or since it's just changing the air coming into the car the vehicle can compensate for it?

When does a car actually need to be tuned when switching parts on it.
 
01Steeda said:
If people are willing to spend 200 for 1hp from a CAI then why is 300 to much to spend for 10-15? and yes the compression is raised almost 1 point... 9.5:1... whoopdey doo :rlaugh:

PI swap comp is more like 10.3 ish...but if that person is on a budget and staying NA then that compression is a good thing.

CAI is easily installed, PI heads aren't for most on here. Maybe thats why some opt to not do a Full PI swap. :shrug: Also don't forget you have to buy gaskets and head changing kit etc so that $300 can become $500 real fast.
 
DropTopPony said:
PI swap comp is more like 10.3 ish...but if that person is on a budget and staying NA then that compression is a good thing.

CAI is easily installed, PI heads aren't for most on here. Maybe thats why some opt to not do a Full PI swap. :shrug: Also don't forget you have to buy gaskets and head changing kit etc so that $300 can become $500 real fast.


ok so you spend double the money for 10 to 15 times the results :shrug:

and if the compression goes to 10.3:1 wouldnt that be a 2 point raise? Am I mistaken are dont the 4.6L have 8.5:1?????
 
Never said heads were a non-issue. I'm just pointing out alternatives to a headswap to get comparible numbers. If I'm not mistaken it is a hell of a lot easier doing a cam swap than a headswap. If it gets you similar numbers on the NPI heads then why do a headswap? My car still has a better ET in it as it sits. HP numbers is one thing. What you do with that HP is another. I'm running with PI cars now. Wouldn't be a stretch to spend a few more bucks on headers and be trapping with stock LS1 cars. ***Oh...did I just say that?***

Another point is the newer 4.6's are built to work together...bottom to top. Bolting on items in a mix/match fashion such as a PI intake on NPI heads leaves alot to be desired. I'd be interested in a nice upgraded intake for the NPI if they were not so expensive.
 
I understand what your saying rick. I am just pointing out that with the heads you can get so much more out of all those extra bolt ons. Imagine if My car had TB,Plenum,4.10's(do now) and cams when I ran those times.. I woulda been 13.3 at the least. I should have run faster than 13.0 with my head cam setup... but not traction and a bad driver limited what I got out of it.
 
The stock compression ratio is roughly 9.0:1 to 9.4:1 on the NPI cars, adding PI adds bumps that 1 pt to 10.0:1 to 10.4:1 on the NPI block. PI cars have roughly a little more compression stock than the NPI cars did roughly 9.3:1 to 9.7:1.

Now we are talking 1/4 miles. Do not forget my TBird with the mods I pointed out earlier( page 2 of this thread ) is running 14.1's. Friends TBird with a complete 01 Mustang GT 4.6 is running 14.5's with more mods than me and his car is lighter than mine. Seems to me the heads didn't help him. There is modified 99 - 04 GT's that are running slower than my TBird. There is an 04 Mustang with a SCT tune, 3.73's, Nittos, and a few other things and can only get a 14.5 out of his car. Silver04GT is his Stangnet name.

My track elevation is 1600 feet above sea level. So I think at a different track at a lower elevation, my Bird breaks into the 13's easily. I would also be betting that my Bird is a lot heavier than your Vert Mustang.

I am not saying NPI heads are better than PI's. I am saying that each has their use. For a budget of $1000.00 - $2000.00 dollars, it is really tough to beat the PI headswap. Under a $1000.00, the PI intake swap with some type of upgraded cam swap is very tough to beat.

I am going to keep saying that PI intake an PI cam swap in a NPI headed car will make very similar power to a complete PI motor with similar mods. I have not seen any evidence that points the other way for me to change my mind on that.

As I pointed out earlier, a PI intake, PI cam TBird makes roughly 210 - 220 RWHP. PI motor swapped Tbirds make roughly 210 - 220 RWHP. PI headswapped Tbirds make roughly 230 - 235 RWHP. There is some cars that vary outside of those numbers.
 
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.

i paid 200.00 for the heads/cams low miles
88.00 for intake
gaskets, etc.

good idea.