96-98 vs. 99-04?

Discussion in 'SN95 4.6L Mustang Tech' started by tjmaxx, May 29, 2006.

  1. Can someone tell me what the difference in the 96-98 4.6 engine compared to the 99-04 4.6? why does the newer ones produce more power what did ford do differently? I also heard that it is very hard to get any power out of the 96-98 mustangs, is this true? My car has a Mac 2 1/2 inch inch x pipe with 2 1/2 inch catback with 3 1/2 inch tips. It also has a fenderwall cold air intake, it has platinum plugs with summit/ frpp 8mm wires. what kind of horsepower should I be putting down? and what are some good basic boltons? thanks in advance.
  2. i know the big difference is in the heads, i have an 03gt and i guess there is a 40-60 HP difference in non PI to PI heads, i guess i would shoot for trying to get some of these heads along with a TB and plenum setup, as always gears are a plus, maybe cams as well and possibly some headers, i also believe there is a differnet type of intake you can get as well. Just depending on how much you want to dive into it. with my 03 im looking at a few options, its just a matter of spending all the money.. :). Look at companies such as VT, Modular Power House, Fox lake Racing, FRPP, ETC.
  3. thanks for the quick reply. I do have 4.10's and a king cobra clutch and a shorty shifter. It seems pretty fast with the mods it has. I was thinking about doing something like pullies.
  4. Two letters PI. PI stands for Performance Improvement - Ford added PI cylinder heads, camshafts, and intake manifolds to the 99-04's - this is why they make more power. It is harder to get power out of NPI (Non-PI) motors, but a very common mod is a PI swap; this is where you change the heads, cams, and intake from a PI motor and put them on your NPI block.

    You should be making between 200rwhp and 225rwhp. Good bolt on upgrades included long tube headers, nitrous kits, more aggressive cams, and superchargers. Aside from those, there aren't many things (besides the aformentioned PI swap) which will get you over 10rwhp per-mod gain on a NPI car.
  5. You did'nt say what year you have, but '96-'97 were 215HP and '98 were 225HP so I'd say with your mods you'd probably be at 190HP-200HP at the rears.
  6. The 99-04 GT's also have a more aggressive tune in the ECU from the factory.
  7. I have a 96 gt that I just bought. Do these engines have dual overhead cams? sorry for the stupid questions but this is my first stang and I only know about the 5.0's. I have only driven 5.0's and mine seems to pull alot harder than the few 5.0's I have driven, but that could be from the 4.10's and king cobra clutch.
  8. SOHC
  9. O okay thanks. Man you guys reply fast, lol:SNSign:
  10. The PI heads have very little to do with the Power Gain. The newer motors have more aggressive cams, better intake and a more aggressive tune. The biggest choke in the NPI motor was the intake, not the heads. People who have done just the PI Cam and PI intake swaps ARE MAKING the same RWHP as a 99+ car is with the same mods. NPI cars that do the PI headswap as well see a increase in Compression which makes another 10 - 15 RWHP than a 99+ car does.
  11. +1

    Its all about which body style you like best. Your gonna get mod fever either way, and make the power you want.

  12. +1
  13. Yeah true - also ported NPI heads have been known to flow well. What was that one company was selling ported NPI heads??

  14. this is false info. I know of 3 cars with the pi cams and intake that were nowhere close to my numbers with similar mods. you are correct on most, but not the numbers. heck I know of a car with aftermarket cams that isnt making what I was with just pullies and exhaust.:shrug:
  15. Renegade Racing did the heads for my 5.0L Big-Bore NPI motor. No website, just email to get ahold of him. Steen Racing also does NPI heads.
  16. Depending on the place/person porting the heads.Ported NPI heads
    will outflow ported PI heads.I know Renegade Racing and Steen Racing
    does some great porting work on the NPI heads.Correct it's not the heads
    that constrict the airflow on the 96-98 cars it's the intake manifold that
    is the real bottle neck.
  17. Got any dyno numbers of a NPI car with just PI intake and cams making 230rwhp in a 5spd?

    I remember seeing a PI cam swap alone and he gained something like 2rwhp.

    How many compression points? 1 to 1.5? That is an awful lot.
  18. Kris Danner when the PI Intake swap was first done, as a test car installed PI Cams, PI Intake, 80 mm LMAF( Lightning MAF ) and on a 96 Cougar. The car made 220 RWHP through the 4R70W and an IRS. That is bang on with PI motor swapped TBird Cougar. Now from my personal experience, my 96 TBird with these mods:

    Removed Air Silencer, 80mm 03 GT MAF, 04 GT intake Tube, 04 GT Intake, PI Cams, custom exhaust, 3800 Stall TC, 3.73 TL rear end, SCT Tune. This car weighs just under 4000 lbs and is running low 14's, remember this is an auto and IRS equipped car. I am hoping with the 4.30's that it hits 13's, just have not taken it to the track yet.

    This car has beaten 99+ Mustang GTs in the 1/4 and beats my friends 01 GT motor swapped TBird that has more mods done to it. I have heard of a few cases where the PI intake and PI cams swapped cars are not making the power, but they usually are. As I stated earlier the Intake Manifold is the biggest bottleneck in the NPI car.
  19. Whats a good intake manifold to get for my 96?
  20. Just pick up a PI intake manifold, you can get it from gefracing.com, mustangtuning.com, and a whole host of other places. For a basically stock, N/A car, the PI manifold provides more than enough flow