RFY Headers on 2000 NSX?

[Bigfieroman]

Hello,

I am interested in getting headers for my 2000 NSX, but they are different from those of the earlier cars. I was specifically interested in the RFY headers, which are NA1-only. I was told, offhand, that I could make they fit my NA2 with a set of "NA1-Style test pipes". FYI the car currently has stock cats/headers and an aftermarket exhaust of unknown brand.

1) Is that true?
2) What options do I have if I would like to retain catalytic converters, other than custom? I am open to the idea of high-flow aftermarket cats if the stock cats are a source of restriction, but from what I have read, people complain about the stock headers or stock exhaust as restrictions before the catalytic converters.

Thank you in advance.

 

[Justinsx]

Remember reading about the difference between NA1 and NA2 headers in some old posts. The reason for us NA1 owners to get these upgraded headers are in factor our oem are really just manifolds made out of cast iron which is heavy and restricted. A gain can be realised from upgrading a header… but more likely to be the reduced weight. While for NA2, the gain is less.

Correct me if I am wrong. I would love one RFY header in reasonable price though.

 

[Honcho]

You will gain over the NA2 factory headers, but not nearly as much as NA1 manifolds. There are some fitment issues for the different years. They can be categorized as:

91-94 --> Most headers are made to fit this exhaust setup.
95-99 --> The cats changed. so the headers line up with a ball-joint connector now. NA1 and NA2.
00-05 --> The front header will fit, but the rear header is short by 20 mm due to another change in the cat.

Thus, headers made for the "NA1" (they usually meant the 1991-94 coupes) will actually fit 91-99. 91-94 cars will need "header adaptors" to allow the manifolds to connect to the cats. 95-99 bolt right up to the cats. 00-05 need to be special order because they need to lengthen the rear header by 20 mm.

Thus, the RFY will be too short in the rear for your 2000 NSX. It won't make it to the 2000 cat. I have 00-05 headers on my NSX and I had to have an exhaust shop lengthen the rear adapter by 20 mm since I have the 91-94 cats. If you wanted to use the RFY, you could swap in a 95-99 rear cat and it would fit.

 

[RYU]

I'm fairly certain RFY has the right adapter for you. It's worth emailing them.

 

[Bigfieroman]

Ok, thanks all. Are the stock cats much of a restriction?

 

[Honcho]

Ok, thanks all. Are the stock cats much of a restriction?

Not at all on stock power.

 

[Bigfieroman]

Not at all on stock power.

Thank you for all of the detailed information!

 

[MexiRicer]

To quickly answer your question, yes you can make them fit. You will need to run 91-94 cats or test pipes and 91-94 exhaust. I run Fujitsubo headers on my 1997 and I have custom titanium test pipes. When spec'ing our my test pipes, I had the fabricator add 02 bungs toward the flange that mates with the exhaust, same like how where the 02 sensor is located from factory. So, there will be the need to add for the additional 2 02 sensors that the 91-94 don't have. I do know that the 00-05 cars have LEV cats, but I am not familiar with the parameters on those models; if the ECU looks for something in particular in regards to emissions.

 

[NSXnZ]

As mentioned above, I run 91-94 RFY headers on my 95 with 91-94 fitment Sard HFC. Only thing was my 95 needed o2 sensor bungs welded onto the cats. Then 91-94 aftermarket exhaust fit with no adapters also.

 

[OE2]

I have a ‘98 and in the process of having my na1 T3TEC headers installed. I got na1 KSP hfc and have been running tubi style exhaust with adapters. I am hopeful with O2 bungs welded post cats it will be an easy installation.

 

[OE2]

All done and pretty straightforward

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Everything bolted up nicely, there was a transition pipe hanger that needed to be moved so there was some welding aside from the O2 bung but nothing major. I have already dyno'ed stock so when the next dyno day comes around I'll dyno with these headers. An unintended benefit is that the tubi syle muffler was off center before and now that's corrected due the full header back change to NA1 parts.

 

[MexiRicer]

That’s pretty neat. I did not know we can embed instagram posts here!

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