Headers for 02+ Auto

[unc0808]

I know this is a slim to none chance, but worth asking since there are some of us out there that may be interested.

As I hear the oem 02+ 6MT headers are about as free flow as you can get, I know there is improvement with the NA1 3.0.

Any vendor willing to find a local AUTO owner, test, post performance numbers and possibly make a small batch? If the numbers make sense with the cost, I would for sure be interested.

 

[EuroBoutique]

What you are asking is a needle in haystack - just making any part for the NSX is already exclusive but to make it specifically for an AUTO, that would be special.

Plan to pay at least $2k+ but best bet would be LoveFab, ask Cody

 

[unc0808]

Hence the very first sentence of my original post. Thanks.

 

[Stephen@NCAutoUSA]

I guess going upon the same assumption that there's minimal performance gained between stock 02 headers and regular aftermarket ones the auto would be the same too.

It's dollar for dollar though and what it comes down too. There are some nice headers out there and some run 2k while others run less than half that amount. It just depends but if I were auto I would just opt for some used taitecs/comptechs or pride headers.

I also don't think headers auto vs manual have any difference between them. I may be wrong though.

 

[unc0808]

I never looked into NA2 OEM headers vs aftermarket but I am willing to bet they have similar results when put onto an NA1 manual.

I personally worked with a vendor that confirmed their headers would fit the auto, so I bought them, installed and confirmed that in fact do NOT fit an auto so I had to ship them back. Most other vendors confirmed theirs did not fit the auto either so there is definately a difference between manual vs auto setup.

Jim

 

[dablackgoku1234]

Since you've been under your car, what headers does your car have now?

 

[unc0808]

Right now I am back to the factory OEM NA1 3.0 auto header.

My installer said the reason the aftermarket headers did not fit was because - "Rear Header does not clear transfer case housing"

 

[jtrikakis]

Most, if not all well made headers clear it. I have used DC and LoveFAB F1 headers and they both clear.

 

[unc0808]

Most, if not all well made headers clear it. I have used DC and LoveFAB F1 headers and they both clear.

But are you manual or auto? It's different.

 

[dablackgoku1234]

When you say "OEM NA1 3.0 auto header", is that the left pair or right pair in the picture above? I do not have an automatic, so I'm not sure what they put into 97+ automatic cars. I would assume they put in the 97+ style.

 

[unc0808]

Checking with my installer as I am not sure to be honest.
I do know though that the vendor who sold me their headers that claimed they fit, look similar to the ones on the right but not exact. I attached a pic of them.

 

[jtrikakis]

Good point. I have a manual transmission and I noticed looking at the auto case, it is different. Learning something almost everyday on Prime. Thanks.

 

[Stephen@NCAutoUSA]

Someone I'm friends with I reached out to last night said he has dc sport headers and he's automatic. No modifications needed.

There are heat shields probably on your headers. If you can get a picture or two posted we can tell you what you have.

 

[unc0808]

Someone I'm friends with I reached out to last night said he has dc sport headers and he's automatic. No modifications needed.

There are heat shields probably on your headers. If you can get a picture or two posted we can tell you what you have.

what year is his NSX?
The 02+ are different from the 91-94 which I hear DC made for those years.

 

[Stephen@NCAutoUSA]

I believe his is a coupe. Although the headers are slightly different there are adapters that make any header fit any year nsx. The specifics I actually am unfamiliar with and the routing of where the small collectors merge but I know there are adapters non the less. I don't know if they interfere with the trans casing or not.

 

[BrianB]

Headers will fit auto NSX's I have them the DC on my 91. The only difference in the newer ones would be the exhaust and cats I would think? The DC offer adapters you might want to check into them. Also worst case you could switch to a 91-94 exhaust, then get some 91-94 high flow cats and add a O2 bung behind the cats for the obd2 setup. Some companies will say it won't fit auto for the simple fact they haven't tried. Like Mishimoto on their site says their radiator will only fit stick. Assuming the NSX has a rad mounted transmission cooler. But it doesn't. And the radiator fits fine. I can only speak with certainty on my situation with a 91 auto NSX thou.

 

[whrdnsx]

Its the cheaper OBX & Topspeed headers I have had problems with. The rear bank header is too low & hits on the gearbox casing. the front header is also pointed downward which then pushes the exhaust tips up into the valance.
You get what you pay for I guess.

 

[A.S. Motorsport]

Its the cheaper OBX & Topspeed headers I have had problems with. The rear bank header is too low & hits on the gearbox casing. the front header is also pointed downward which then pushes the exhaust tips up into the valance.You get what you pay for I guess.

+1 the fit very poorly, I've seen them hit the rear cross member as well. Good quality headers like, TaiTec, Comptech, etc fit just fine.A acquaintance of mine has the 3.2L headers on his 3.0L auto and should have the dyno run's for it.

 

[greenberet]

Since you've been under your car, what headers does your car have now?

Looking at the parts catalog, from 1991-1994 automatic and manual NSXs used the exact same cast iron exhaust manifolds and downpipes. In 1995 new downpipes were introduced and those were bolted to both automatic and manual NSXs. In 1997, manual transmission NSXs got 3.2 liter NA2 engines and tubular headers. Automatic NSXs didn't - they continued using 3.0 liter NA1 engines, 1991 specification manifolds, and 1995 specification downpipes until production stopped in 2005.

I wonder how different the external dimensions of the transmissions really are. It's good to hear that the 1997+ OEM manual headers will clear automatic transmissions. From what I've heard the OEM 1997+ manual headers don't boost power as much as good aftermarket headers do but they're way better than the cast iron manifolds.

 

[unc0808]

I believe his is a coupe. Although the headers are slightly different there are adapters that make any header fit any year nsx. The specifics I actually am unfamiliar with and the routing of where the small collectors merge but I know there are adapters non the less. I don't know if they interfere with the trans casing or not.

I know there are adapters but I have yet to be told by any vendor, any NSX auto owner or Prime member for that matter than A) this header fits an 02+ auto and B) this adapter goes with this header to fit an 02+ auto. I have done a lot of research with most vendors here and they all confirm theirs do not fit, and no mention of adaptors.

Headers will fit auto NSX's I have them the DC on my 91. The only difference in the newer ones would be the exhaust and cats I would think? The DC offer adapters you might want to check into them. Also worst case you could switch to a 91-94 exhaust, then get some 91-94 high flow cats and add a O2 bung behind the cats for the obd2 setup. Some companies will say it won't fit auto for the simple fact they haven't tried. Like Mishimoto on their site says their radiator will only fit stick. Assuming the NSX has a rad mounted transmission cooler. But it doesn't. And the radiator fits fine. I can only speak with certainty on my situation with a 91 auto NSX thou.

I already have the pride v2 so not going to switch exhausts. I really dont want to go through an extensive amount of work to make headers fit the car. Just simple bolt on with/without an adapter but seems nobody has really tested these waters on an 02+ auto or has come up with actual proof that they have them on their car that fit. Vendor or NSX owner.

Like said, I already bought headers from a reputable vendor that said they'd fit, my installed proved they didn't, and I had to return them. Not looking to go down that road. Looking for someone to tell me 110% this is what you need to buy and will fit.

+1 the fit very poorly, I've seen them hit the rear cross member as well. Good quality headers like, TaiTec, Comptech, etc fit just fine.A acquaintance of mine has the 3.2L headers on his 3.0L auto and should have the dyno run's for it.

Yes but what year because 97+ auto is different from the 91-96 auto I believe.
If it's 02+ then I would love to know the set up and numbers.

Looking at the parts catalog, from 1991-1994 automatic and manual NSXs used the exact same cast iron exhaust manifolds and downpipes. In 1995 new downpipes were introduced and those were bolted to both automatic and manual NSXs. In 1997, manual transmission NSXs got 3.2 liter NA2 engines and tubular headers. Automatic NSXs didn't - they continued using 3.0 liter NA1 engines, 1991 specification manifolds, and 1995 specification downpipes until production stopped in 2005.

I wonder how different the external dimensions of the transmissions really are. It's good to hear that the 1997+ OEM manual headers will clear automatic transmissions. From what I've heard the OEM 1997+ manual headers don't boost power as much as good aftermarket headers do but they're way better than the cast iron manifolds.

I read somewhere that manual NA2 3.2 OEM headers to aftermarket is nothing significant, but from manual NA1 3.0 to aftermarket is more significant. Wonder what the numbers would be from NA1 3.0 to OEM 3.2 headers on a manual.

 

[A.S. Motorsport]

Well let's clarify a few things

1990-2005 NSX auto's are basically all the same mechanically (yes, '94 had f-matic added, and yes, OBD-II and cats change for smog reasons)
The cast iron header is specific to the 3.0L engine so 1990-2005 auto still uses it.

Any manual exhaust line that is properly made fit's a automatic any year.

The later automatics got the ball socket style flex section where the early manuals had the weak braided connection (doesn't change routing or fitment)

A 2002-2005 automatic, is mechanically 99-05 they just have spring LMA's and LEV catalyst to pass smog.
the later automatics where equipped with adapters so they could use the manual exhaust of the later years.


Are you willing to disclose the name of the header manufacturer?


Also the acquaintance in question has a 1997, he installed the 3.2L headers.


For reference the exhaust layout diagram for 94-05 automatics

 

[greenberet]

I read somewhere that manual NA2 3.2 OEM headers to aftermarket is nothing significant, but from manual NA1 3.0 to aftermarket is more significant. Wonder what the numbers would be from NA1 3.0 to OEM 3.2 headers on a manual.

As you can imagine, that topic has interested NSX owners since 1997. Hapa88 did a dyno test and posted the results here.

Swapping out the OEM cast iron manifolds for the 1997+ manual headers AND swapping out his OEM 1995 muffler for an OEM 2003 manual muffler, he found 14.6 rwhp. A bit of that was probably due to the muffler since the later (manual transmission?) mufflers had small bellmouths inside the chambers whereas the earlier ones didn't.

If I remember correctly, people have found something like 10-15 rwhp swapping out cast iron manifolds for OEM 1997+ manual headers in manual transmission NSXs. Swapping out the cast iron manifolds for good aftermarket headers, people have found something like 20 rwhp in manual transmission NSXs.

 

[unc0808]

Well let's clarify a few things

1990-2005 NSX auto's are basically all the same mechanically (yes, '94 had f-matic added, and yes, OBD-II and cats change for smog reasons)
The cast iron header is specific to the 3.0L engine so 1990-2005 auto still uses it.

Any manual exhaust line that is properly made fit's a automatic any year.

The later automatics got the ball socket style flex section where the early manuals had the weak braided connection (doesn't change routing or fitment)

A 2002-2005 automatic, is mechanically 99-05 they just have spring LMA's and LEV catalyst to pass smog.
the later automatics where equipped with adapters so they could use the manual exhaust of the later years.


Are you willing to disclose the name of the header manufacturer?


Also the acquaintance in question has a 1997, he installed the 3.2L headers.


For reference the exhaust layout diagram for 94-05 automatics

Do you know what the 97 NSX did to fit the 3.2 headers?
Also looking for pretty much bolt on, and no cutting or fabricating.

As you can imagine, that topic has interested NSX owners since 1997. Hapa88 did a dyno test and posted the results here.

Swapping out the OEM cast iron manifolds for the 1997+ manual headers AND swapping out his OEM 1995 muffler for an OEM 2003 manual muffler, he found 14.6 rwhp. A bit of that was probably due to the muffler since the later (manual transmission?) mufflers had small bellmouths inside the chambers whereas the earlier ones didn't.

If I remember correctly, people have found something like 10-15 rwhp swapping out cast iron manifolds for OEM 1997+ manual headers in manual transmission NSXs. Swapping out the cast iron manifolds for good aftermarket headers, people have found something like 20 rwhp in manual transmission NSXs.

Thanks for the info. I am certainly intrigued to know more numbers on the difference between 3.2 oem headers on an auto compared to aftermarket headers. 15-20+ would be the ideal numbers to make it worth while for the potential purchase price.

 

[unc0808]

I may know of a set of headers that will fit. Still working things out but will update this thread if I buy/test fit.

 

[BrianB]

What brand headers did you try? It should just be a bolt up deal. No custom work needed.

Also on a auto NSX the gain isn't as much as the stick NSX. So you're looking 10-15whp for the headers. But that's actually cheap for that much whp with one mod.