preston145

So my question is i have a 98 2v mustang gt that is pi swapped with 99 gt heads. So my friend has offered to sell me longtube headers off his car with an o/r h-pipe for 200. I know its a heck of a deal. so will the longtubes off his 4v 99 cobra fit my 99 2v heads along with the h pipe? I researched this and what i have read is that it will work but i need to use 2v gaskets. some one enlighten me! please let me know asap! Thanks! And if there's anything else i need to know please do!

mrtstang

Nope! They are different designs. It won't work.

preston145

are you positive???

mrtstang

Yes i am

preston145

****!

preston145

ok so i have been researching this pretty much all night and i came across this guy who did a swap. Basically what i get out of it is that the 99-04 porting is a little different but that the bbk longtubes on a 99 4v will bolt up to the 99 2v with minimal porting difference. just read it and let me know.

"Alright so the intake portion is taken care of, what about the exhaust? 2V Mustang headers are physically the same. The 2V uses a round port design as the 4V mustangs use an oval port design on the flange…and there are even 2 styles of oval design. 99/01 Cobras use a TRUE oval design and the 03/04 Cobras, Mach 1s and Aviators all use a ‘square’ oval port design. Will any header work with either? Yes, but there will be a LITTLE and I mean LITTLE port match difference. You can use stock any Cobra or Mach 1 manifolds on either style head and it will work and will bolt up to your stock 2V exhaust the same. The only difference in the exhaust from Cobras and GTs/Machs is the Cobras use IRS so the cat back is different, and the headers use oval port designs, other than that, all the other exhaust bolts up in the same locations. So take stock Mach headers, and bolt them up to your stock GT exhaust…no adapters needed. You will however need a new passenger manifold collector gasket (about 7-10 bucks from Ford)
I chose to get 99-up BBK longtube headers and matching O/R h-pipe. Now if you have emissions in your state, you might want to consider keeping stock manifolds and all the emission equipment. I stated earlier that the ports are different from 99 Cobras to 03/04 Cobras, Machs and Aviators, but I still got headers for 99/01 Cobras. BBK doesn’t make a 03/04 specific flange, but it does work. I have them on my car and they have VERY, VERY minimal port mismatch. I have seen other headers that have horrible port mismatch, but from my experience the BBKs aren’t noticeable and I doubt I am losing any power from it. The only other companies I know of that make specific 03/04 headers are SLP and Kooks. Look to spend about 1000 bucks for just the headers. I got my headers and H-pipe for $525 shipped. These are the ceramic coated ones. I believe a vendor on SVTPerformance.com is still selling these for this GREAT price! That is where I got mine. Also if you get Longtube headers you need to get some O2 extension harnesses. I also got these from BBK. I think I paid something like 35 bucks.

IRSmart

also gotta think if the header bolts are even in the same place. after all, they're entirely different heads