Header question...

[OneRedNSX]

I am installing a set of headers from a 2002 on my 1993 NSX. In preparation of the install I am trying to purchase new gaskets so I don't have to worry about it.

My questions are as follows:

1. Which gaskets do I get?

- 1993 Gaskets (PN 18115-PR7-A02)
or
- 2002 Gaskets (PN 18115-PBY-J02)

2. Where to extend the pipe?

- From looking at the drawings, I noticed that there are only exhaust hangers on the cats. Therefore, they have to remain in the position that they are in to be properly supported without having to make more modifications. That being said, is my best bet to cut the cats right before the header-side flange and have the pipe extended there so that I preserve both the cats factory location and the factory flanges on all connections?

 

[davidf]

+1 on the gaskets, this will be in my near future.

 

[OneRedNSX]

Anybody have any thoughts on this? I need to order parts haha :tongue:

 

[L8apex32]

I'll take a stab at this since I'm in the middle of putting aftermarket headers on my '92.

As far as manifold gaskets, its seems unlikely that you'll need to replace them. They look like 3 or 4 thin metal stampings loosely held together... if held at all. They just sandwich up there between the manifold and head. Although their age shows in the color, physically they seemed in tact and could be re-used. (My header kit came with new gaskets so I'm using them.)

Regarding the header to cat ring gasket, I am not sure. My headers came with new o-ring gaskets but I haven't seen how or where they fit. Maybe I have to pry something out of the cats that these replace.

For question #2, the way I understand it is that aftermarket headers, meant for an early NSX, take adapters (extensions) to get them to fit later model exhausts. That means to me that later exhaust headers are longer than early ones. I believe that your new headers from a later NSX will be too long to join with your older/original cats. One way to make later headers work is to switch to later year cats. I am not sure what pipe work would be needed without switching to the later year cats.

This, btw, is why I didn't go this route. I didn't find a good way to mount a later NSX header to an earlier cat-back system.

I hope this helps.

 

[OneRedNSX]

well the first thing i am worried about with the gaskets is why they changed b/w 93 and 02. i dont want to find out after i have everything off haha.

as far as the cat pipe i am not worried about that yet as it will be easy to overcome once i have the headers on.

 

[nbovelle]

For Question 2:

SOS makes adapters to extend the late model headers on the early models.
I used it and it worked fine.
The link is here:

http://www.scienceofspeed.com/produ...s/NSX/ScienceofSpeed/factory_header_adaptors/

 

[OneRedNSX]

For Question 2:

SOS makes adapters to extend the late model headers on the early models.
I used it and it worked fine.
The link is here:

http://www.scienceofspeed.com/produ...s/NSX/ScienceofSpeed/factory_header_adaptors/

what year did your headers come off of? i have 2002s and it says it may require modifications (which i dont want to buy adapters then modify them...)

 

[nbovelle]

My headers came off a 97.
You may try doing a search.
I think I may have seen a post a while back about the differences in NA2 headers between years.

Good luck,

Nate in DC

 

[OneRedNSX]

My headers came off a 97.
You may try doing a search.
I think I may have seen a post a while back about the differences in NA2 headers between years.

Good luck,

Nate in DC

I looked but i can't see anything that would change the fitment of the adapter. Something about air jets in the head that might have required a different port pattern slightly but nothing on the other side that should mess up an adapter...

 

[DPG]

Call SOS, they more than likely will have the answer for you. I know Chris loves it when I bother him, but as long as I buy something every once and a while, he is cool. :wink: