difference between 97 & 98?

[SRT Handz]

I still conquer that all NPI heads on mustang 1996-1998 are exactly the same..... I seen this with my own eyes.

The exhaust ports are even the same shape (Round) on NPI and PI heads. Thats why you can use the same headers on cars 1996-2004 2V V8 Cars

 

[MustangChris]

On the technology side of the (96-97)/98, the P.A.T.S system which is your alarm system is located through the dash cluster I believe, and the 98's is in the PCM/ECU. This fact is irrelevant as well but the 98 Cobra has the fastest ECU processor, perfect for having a high revving car making a lot of power. People who know about this look for them, and its hard to find.

could they just upgrade to a 99-04 cobra system?

I still conquer that all NPI heads on mustang 1996-1998 are exactly the same..... I seen this with my own eyes.

The exhaust ports are even the same shape (Round) on NPI and PI heads. Thats why you can use the same headers on cars 1996-2004 2V V8 Cars

so be it, ive never seen 98 heads out of a car... and you're welcome to your own opinion.

GT worked for teksid, so he is still a very reliable source of information on this subject.

as i mentioned above (with a *perfect* example) the exhaust port has very little to do with the intake port design (in this case), let alone cc size, etc.

 

[Dalamar]

isn't that stock sausage turd a beauty!!

it's Cat-tastic!

 

[MustangChris]

isn't that stock sausage turd a beauty!!

it's Cat-tastic!

pretty knarly, huh? crazy they even found enough room for all of it under our cars. lol.

 

[GDTrumbo]

I still conquer that all NPI heads on mustang 1996-1998 are exactly the same..... I seen this with my own eyes.

The exhaust ports are even the same shape (Round) on NPI and PI heads. Thats why you can use the same headers on cars 1996-2004 2V V8 Cars

Dude! They only modified the exhaust ports slightly. You won't see any difference at the head/manifold interface opening. If you do a profile check every 5mm along the port from valve seat to the manifold opening on both heads, you will see the difference. Dave Sobota and I did the 2V drawing mods and the mathematical checkpoint layouts for the CMM. 2 "cubed" castings were CMM checked and X-rayed per shift.

Handz, Handz, Handz :angry7: Lying doesn't get me anything. Research the casting #'s.

 

[MustangChris]

so GT,

what youre basically saying is looking at the exhaust ports on heads is much like looking at different girls cooters, and the only REAL way to find teh difference is for a full (sometimes all-night) diagnosis of the said "port" in question? lots of measuring, lots of observing, maybe a friends help if you have to get into some strange positions with your tools?

 

[red95r]

so GT,

what youre basically saying is looking at the exhaust ports on heads is much like looking at different girls cooters, and the only REAL way to find teh difference is for a full (sometimes all-night) diagnosis of the said "port" in question? lots of measuring, lots of observing, maybe a friends help if you have to get into some strange positions with your tools?

:laughing5:

 

[GDTrumbo]

Welp.......... Just knock the bottom out of it!

GT

 

[MustangChris]

hahahahhha.


- hi-jack ended -

GT, what exactly did you do at Teksid? and why was there a change in head design the year before the PI swap? im SURE they had to know PI was coming out??? wasnt it already on the crown-vics (???)

from a business stand point, it litterally sounds like a toilet flushing, to me.

 

[GDTrumbo]

I was doing 3D CAD work in the tech office and was closely tied in with the dimensional lab. As far as the exh. port change, who knows what was on Fords mind at the time. It seemed a bit silly economically to me also.

I don't think the PI castings were used on the Crown Vic's until the '02 Romeo. The '91 thru '04 4.6L has a strange
history. Pay close attention to casting numbers............

GT

 

[MustangChris]

oh. ford paid for it??? thats understandable... i thought you guys were doing it because of contractual agreements or something.... (???) but i figured id ask...