Question about getting the AC headers for 2000 X and relocating the cats!

[superslidestyle]

I'm thinking about getting the 4x4parts.com AC headers for the 2000 Xterra V6, but they're telling me that installing these will move/eliminate both catalytic converters and if I wanted to keep both the cats on , that I should have them put in farther down the exhaust pipe.  Has anyone else done this?  And if so, where would I have the 02 bungs welded in for the 02 sensors?  Would the wires for the 02 sensors reach?

Here's the link to the headers in question:
https://www.4x4parts.com/catalog/product_info.php?cPath=367_266_530&products_id=4879

[Bobby B.]

Bear in mind that headers may hose you on the visual part of the smog check. 

You have an 00?  Reason I ask is that the X has four cats, but federal 00 models only had two, so you could, conceivably pass the visual then.

Usually, 02 sensors are in front of and behind the cats, showing that they're doing their job.

[XterracerX]

Dear Santa,

Can you please make CARB legal headers for the 1st Gen Xterra?

PS: If possible, can it be powdercoated in yellow?

Thanks,
Timmy

*sigh

I wish we can write or email the manufacturers and get them going on making 50 state legal headers just like the new gen X.

[superslidestyle]

Mine only has two cats practically on top of the manifolds.  I'm going to have to replace both cats with the Universal Magnaflow metal-core hi-flow units and fabricating my own flanges from stock steel.  As for the visual test, I plan on trimming the heat heat shields (if necessary) and using doubled-up metal tie wire to hold them in place during the inspection.  It actually worked on my Nissan 240SX race car with 4-2-1 HotShot headers.  What do you guys think?

[xperienced]

I called and buged Doug Thorley headers to make some headers that are street legal.  According to DT, if we get 10 people or so they will cut the price and figure out a way to make them smog legal.

I'm willing to get a set if they will pass smog.

DT suggested taking a set of Frontier headers and adding a custom y-pipe.  The only problem is that you will have to install the O2 sensors.

[Bobby B.]

Hopefully the quality of Doug Thorley headers has improved.  We tried to put a set on my friend's Jeep and the fitment was awful, the worst I'd ever seen.

[superslidestyle]

Yeah, I called them and actually spoke with their main fab. guy.  He told me that they just don't have a big demand to make headers for that truck and that we would need to get 10 buyers just to start fab'ing up a set.  This is  without the CARB EO #.

[xperienced]

just another reason to pick up a used but complete z71 motor with tranny, differential, power steering, etc.

I've been looking for a while, but I don't know how much of a fitment issue there will be.

[XterracerX]

Yep! A buddy of mine is experiencing severe exhaust manifold leak (resulting in poor MPG and smog issues) and so I went ahead and called Automotive Customizers and actually spoke to the head of the Research & Development... his name is Mike. Spoke to him for quite a while trying to convince him to make a CARB legal header for 1st Gen X... but to no avail.

Here's the skinny why it is not possible:
1) Due to the strict requirements in CA, the location of the catalytic converters are so specific that removal, modification, relocating or even moving it an inch would render it illegal (for OFF ROAD use only).
2) The time and cost of getting a CARB certification is lengthy and costly.
3) Even if there is a STRONG demand... and he told me that there is... even if it is profitable, due to the very limited space from the engine to the 1st set of cats, it is impossible to create one to even notice any power gains.
4) I even tried convincing him to disregard the power gains and that we're just looking for a better and stronger alternative than buying a replacement stock exhaust manifold, he said that it is just not worth the effort, time and money involved.

He actually explained everything to me and was really patient about explaining the details involved. It's not really the money, the power (if any) gains, but due to the very limited space involved in order to keep the catalytic converters in the same location as designed by Nissan, regardless if there's any power gains, that the R&D is more of an impossibility just to get a CARB approval... even if deemed profitable.

His recommendation, since smog checks are usually every 2 years in CA for most people, is to install the stock exhaust set up during smog check season... and then replace with the non-CARB headers after you get certified and registered. I understand that the system is completely bolt on... but I think it's a lot of hassle to be bolting/unbolting under every 2 years or so... in my own opinion.



I have not heard of Doug Thorley products or have any experience with them.

Hope this helps!