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  • SN95 4.6L Mustang Tech

P.I. Intake opinion

  • Thread starter Thread starter Lostcause
  • Start date Start date Dec 30, 2004
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Lostcause

Member
May 27, 2004
81
1
9
Homestead Fla.
Dec 30, 2004
#1
  • Dec 30, 2004
  • #1
I wanna do a P.I. intake swap on my car,but I don't know if I should do the adapter plates or the R.V.T. with gaskets method. In the furure I plan on using nitrous. So with this said I don't know if the R.V.T. method would hold up due to the added pressure from the nitrous. Any advise or opinion would be greatly appreciated.
 

TweekedGT

New Member
Jul 22, 2004
1,274
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Alberta
Dec 30, 2004
#2
  • Dec 30, 2004
  • #2
You may as well do it right the first time. Get the adapter plates or do the whole headswap. It will be more expensive now but better in the long run. just my .02.
 

Sick96Stang

New Member
Aug 20, 2004
621
0
0
Gilbert, Arizona
Dec 30, 2004
#3
  • Dec 30, 2004
  • #3
Lostcause said:
I wanna do a P.I. intake swap on my car,but I don't know if I should do the adapter plates or the R.V.T. with gaskets method. In the furure I plan on using nitrous. So with this said I don't know if the R.V.T. method would hold up due to the added pressure from the nitrous. Any advise or opinion would be greatly appreciated.
Click to expand...

Definetely do the adapter plates. You wont get nearly as much power from the PI intake if you use the RVT. If you plan on doing nitrous you should also get the PI heads to raise your compression.
 

98GTVortech

New Member
Sep 30, 2003
242
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0
Philadelphia
Dec 30, 2004
#4
  • Dec 30, 2004
  • #4
Better safe then sorry go with the adaptor kit.
 

mr. jones1

New Member
Apr 2, 2005
102
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0
NJ
Apr 2, 2005
#5
  • Apr 2, 2005
  • #5
try my plates.
[/IMG]
on e-bay right now you have to search plates 4.6l. read the description and go to site for instructions.
 
B

bdcardinal

tree hugger
Jun 10, 2003
3,612
16
69
santa barbara, CA
Apr 2, 2005
#6
  • Apr 2, 2005
  • #6
mr. jones1 said:
try my plates
[/IMG]
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7965784004&category=33556

on e-bay right now. read the description and go to site for instructions.
Click to expand...
no sales in the forums.
 

edbo

New Member
Mar 31, 2005
198
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0
Valley, AL
Apr 2, 2005
#7
  • Apr 2, 2005
  • #7
I have a question regarding this. The plates are for just attaching a PI manifold to the current '96-'98 4.6 motors without changing heads for approx 20-35 HP gains. For those of you that have done PI mods (Both Intake and Intake/Heads), what is the average cost for these mods and what are your experiences in the changes in the mods. I also noticed that the head raise the compression to 10:1 so I am sure higher octane gas would be required, so what would minimum octane be to run the full setup? Appreciate any posts regarding these mods.
 

Sick96Stang

New Member
Aug 20, 2004
621
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0
Gilbert, Arizona
Apr 2, 2005
#8
  • Apr 2, 2005
  • #8
edbo said:
I have a question regarding this. The plates are for just attaching a PI manifold to the current '96-'98 4.6 motors without changing heads for approx 20-35 HP gains. For those of you that have done PI mods (Both Intake and Intake/Heads), what is the average cost for these mods and what are your experiences in the changes in the mods. I also noticed that the head raise the compression to 10:1 so I am sure higher octane gas would be required, so what would minimum octane be to run the full setup? Appreciate any posts regarding these mods.
Click to expand...

I picked up my heads (unported) for $550, cams for $90, and intake for $130 all parts had about 10K miles on them. I got a good deal from a local guy because he hooked me up on installation also. PI Intake is worth around 15 rwhp. Cheapest I have seen the parts brand new is $1300 for a kit including all the parts you need. I run 91 octane in my car and I am fine, could possible get away with 87 or 89 octane but I dont know for sure on that. To date the PI stuff has been the best mod I have done so far and I would recommend and 96-98 GT to do that for there first mod.
 

mr. jones1

New Member
Apr 2, 2005
102
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0
NJ
Apr 2, 2005
#9
  • Apr 2, 2005
  • #9
these plates allow you to install the manifold(pi) on your 1996-98 4.6l. no head change required.
Yes you will get better performance by changing the heads and the manifold but it is alot more work and money.
I have seen new 1999 to 2004 manifolds for $160. these plates will give you a good boost in power.
I fabricated these plates, installed them and did get my car (1998 GT) tuned. hp at the motor was 255, torque was 311.
this was with an x-pipe. the hp also peaks at 4800rpm's (not 4400 when stock). this give you more usable power. not bad for around $325 total in parts.
check out the site for details on installation www.unitedmajority.com
 

COramprat

...I can take it. I think.
20+ Year Stangneter
Mar 2, 2003
8,474
1,463
223
Sea of Tranquility
Apr 2, 2005
#10
  • Apr 2, 2005
  • #10
mr. jones1 said:
these plates allow you to install the manifold(pi) on your 1996-98 4.6l. no head change required.
Yes you will get better performance by changing the heads and the manifold but it is alot more work and money.
I have seen new 1999 to 2004 manifolds for $160. these plates will give you a good boost in power.
I fabricated these plates, installed them and did get my car (1998 GT) tuned. hp at the motor was 255, torque was 311.
this was with an x-pipe. the hp also peaks at 4800rpm's (not 4400 when stock). this give you more usable power. not bad for around $325 total in parts.
check out the site for details on installation www.unitedmajority.com
Click to expand...
I'm going to give you a shot...
 
A

Apollo 13

New Member
Aug 9, 2004
45
0
0
Tucson, Az. Its a dry heat
Apr 3, 2005
#11
  • Apr 3, 2005
  • #11
I think I'll try them to. They look awesome.
I don't think pointing out an item for sale that is directly related to the topic should be a problem.
 
T

TGJ

New Member
Mar 30, 2005
1,049
4
0
Apr 3, 2005
#12
  • Apr 3, 2005
  • #12
When I did the PI Intake swap, it cost me $200.00 US to get all the parts needed new. You can still do this swap for a similar price if you know where to shop. That said, I did not use the adapter plates for 3 reasons and 2 of which are still valid to why I still won't.

1) No Adapter plates were available when I did the swap. This the one no longer applies as there is adaptes out there now.

2) The extra cost of these plates is unjustified. There is no data supporting that the plates make more power, than those who did the swap without the plates.

3) The plates raise the intake manifold the width of the plates. What this does is raise the fuel injectors up that width. Now my concern with the plates is: Does the plates affect the fuel injector flow and possibly cause a lean condition? I ask because the fuel is being sprayed higher up than it is supposed to be.

I have pictures of the PI intake gaskets and SVO heads. You could possibly use the PI gaskets and not use any RTV. I would still use the RTV and it is a very small spot on the coolant port that requires it. I have had my intake on over a year and about 35,000 kms on it and do not have any issues with the intake. With that swap, I used the NPI gaskets, when the SVO's go on, the PI gaskets will be used.
 
A

Apollo 13

New Member
Aug 9, 2004
45
0
0
Tucson, Az. Its a dry heat
Apr 3, 2005
#13
  • Apr 3, 2005
  • #13
I wanted the plates since my manifold is pressurized by the Vortech. Didn't want to blow a hole in the RTV if the gap was too large.
 
T

TGJ

New Member
Mar 30, 2005
1,049
4
0
Apr 3, 2005
#14
  • Apr 3, 2005
  • #14
Apollo 13 said:
I wanted the plates since my manifold is pressurized by the Vortech. Didn't want to blow a hole in the RTV if the gap was too large.
Click to expand...

Just an FYI:

You will have no issues if you use the PI gaskets with your set-up. IMO, I would be more inclined to stay away from the plates with the SC, if I was you.
 
D

david l gary

Founding Member
Nov 8, 2002
104
0
0
Millsap Texas
Apr 3, 2005
#15
  • Apr 3, 2005
  • #15
Just use the PI intake and gaskets. A small dab of RTV at the corners of the water passage will do it.
 

CanadaStang

New Member
Sep 7, 2003
2,093
1
0
Mb
Apr 3, 2005
#16
  • Apr 3, 2005
  • #16
If I would have just done the intake, I would have went with the intake and adapter plates from Livernois, they are a little pricey, but I'm thinking the cost of them wouldn't be much more than the tow truck bill if the RTV let go.
 

mr. jones1

New Member
Apr 2, 2005
102
0
0
NJ
Apr 3, 2005
#17
  • Apr 3, 2005
  • #17
well lets see if I can answer all of these questions.
If you use the SVO heads you really should use the manifold designed to match those heads. They are a round port design and have a manifold similar to the bullit design. Not the cheapest way to go. Now if you use the PI manifold there are some issues. yes the water jacket ports do not match up 100%. I have compensated for that in my design (no RTV). The intake ports will not match so plates will enhance this transition.
My plates do this.
As for fuel injector spray pattern-what I can tell you is that my car was rich when dynoed. But not to a point that cylinder wash was an issue or cat damage was possible.

Now do plates make more power that no plates and a PI gasket on a non-PI head. I can not confirm this because I did not do a gasket only install and dyno the car. I did install my plates and gaskets-with the blending on the plate and with an x-pipe I made 255hp and 311tq.
(no heads and no cat back eather)
I have seen post of 15hp without plates. If you follow some of the mustang mag's you will see that 25-35HP with plates is possible.
Now under boost I would want plates because they do blend the ports and provide excellent sealing surfaces.
No issues with a lean cylinder or water leakage or contamination.
If you buy heads (PI) later I would think you could sell your plates for the same price you paid for them.
 

98GTVortech

New Member
Sep 30, 2003
242
0
0
Philadelphia
Apr 3, 2005
#18
  • Apr 3, 2005
  • #18
TGJ said:
Just an FYI:

You will have no issues if you use the PI gaskets with your set-up. IMO, I would be more inclined to stay away from the plates with the SC, if I was you.
Click to expand...

Why would you want to stay away from adaptor plates with a supercharger?? It would seem that the plates would guarantee that you don't lose your intake..IMO
 
H

hbk_136

New Member
Feb 28, 2004
194
0
0
Southeastern GA
Apr 3, 2005
#19
  • Apr 3, 2005
  • #19
98GTVortech said:
Why would you want to stay away from adaptor plates with a supercharger?? It would seem that the plates would guarantee that you don't lose your intake..IMO
Click to expand...


Seems like the adapter plates are the better and safer way to go, especially under more power stress, like from a supercharger.
 
T

TGJ

New Member
Mar 30, 2005
1,049
4
0
Apr 4, 2005
#20
  • Apr 4, 2005
  • #20
98GTVortech said:
Why would you want to stay away from adaptor plates with a supercharger?? It would seem that the plates would guarantee that you don't lose your intake..IMO
Click to expand...

Why would I stay away from the adapter plates with a SC? Because using the plates will cause the car to go lean and you could lose your motor. The only way to find out how lean it is is to put it on the dyno and tune it that way. These plates are not as easy to tune for as if you just swapped over the intake!

What people are not realizing is that a proper calibrated car gets the signal from the MAF telling the EEC how much air the engine is seeing regardless of intake used. A PI intake swap with no vacuum leaks will NOT require a tune, however these plates do. With these plates, you have to command the EEC to provide more fuel because the plates are sitting the fuel injector's higher up on the motor. With a mail order tune at best you are guessing how much more fuel to command.

I have seen over 20 Dyno graphs of cars with PI intake swaps. Some of these cars used Livernois's plates. All of these cars ranged from making 10 HP to 20 HP over the curve and 15 to 36 HP Peak HP over the NPI intake. Livernois's plates swapped cars are in the upper middle of the pack and right on par with the just the gasket swaps in the same area of the country.

Now why I am not using the SVO intake on my car.

1) Cost

2) Requires Hood blanket to be removed and lots of bracing to be cut in a Tbird. It will also dent the hood. What I am going for, is if someone was to pop the hood, the car looks stock. Which intake do I use to accomplish that, PI or NPI? I am not going to choke this car with the NPI.

IMO, the best thing to do is Port-Match the NPI heads to the PI ports and use the PI gaskets with RTV. If I am going to send my SVO's to be P&P, this is the route I would go. However, there was some talk of a gasket being made which had the PI intake ports and NPI coolant ports on modular depot. The guy making these, his first batch failed and then he got injured. If this ever comes back to life, that is a good alternative as well.

I have never seen RTV blow out in a PI intake swapped onto a NPI car or a car with PI Heads using the NPI SVO SC intake. The amount of RTV to be used is very small, and if done properly will not blow out.

With the limited amount of solutions out there, IMO these plates are the WORST ones.
 
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