96-98 vs. 99-04?

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

  1. 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.
  2. I see alot of new PI cams for sale. People buy new PI heads and aftermarket cams. They sell the stock PI cams that came in the heads.

    Look around, PI cams are everywhere.
  3. I still have the ones out of my 04 GT...22K on them, but since they are roller new is just as good as some with 100K...as in there would be 0 difference on the dyno. Im not sure how much I can sell the for though :shrug:
  4. $80-100 is the avg
  5. 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.

  6. 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.

  7. 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:

  8. 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.
  9. What is the elevation where you live in Louisiana COramprat?
    Because your times are good for your mods.
  10. 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...
  11. 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?

  12. 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:

  13. he is talking about mine.

    01 GT vert at that time I had underdrives, 3.73's, flow's welded in and a tune.

    not bad for a heavy pig :D
  14. 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.
  15. 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.

  16. 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?????
  17. 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.
  18. 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.
  19. 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.
  20. i paid 200.00 for the heads/cams low miles
    88.00 for intake
    gaskets, etc.

    good idea.