Anyone know if they make'em?? I can only find em for the 2nd Gen. If not, does anyone have some they recomend?? Much thanx.:aufkopfhauen-big:

AC is the only make that comes to mind...

AC = www.4x4parts.com

oh and i had a big question about them myself and I got it answered. The AC headers DO bolt on directly to the factory down tubes and no modifications to the pipes are required.. So I guess the only problem is the O2 sensors but the wires can be extended I guess or the 02 trick plugs work as well....

oh and i had a big question about them myself and I got it answered. The AC headers DO bolt on directly to the factory down tubes and no modifications to the pipes are required.. So I guess the only problem is the O2 sensors but the wires can be extended I guess or the 02 trick plugs work as well....

Thanks CB! That's a handy piece of info, I hadn't even thought about it lol

I have the AC headers on and yes you'll need O2 extenders on the 2nd set of cats. I was throwing CEL every time I got up around 60+ kph before the extenders, now nothing.

Once the CEL goes off due to a tripped O2 sensor your ECU is running in a closed loop. I stops taking readings from the O2 sensors until cleared (I used my Scangauge) and will essentially force you to run rich.

Oh ok, so you got headers, and you got the federal downtubes then just extended the
O2 sensor to the second cats right, because the first ones were taken out because the federal downtubes are just pipe with no cat? and if you don't have them extended then you trip the CEL(check engine light?) which makes you run.. rich(not sure what that is but it sounds bad lol) BI-GOLLY I THINK I'M GETTIN IT!

...kinda

i thought the headers were illegal?

Once the CEL goes off due to a tripped O2 sensor your ECU is running in a closed loop. I stops taking readings from the O2 sensors until cleared (I used my Scangauge) and will essentially force you to run rich.

It runs in open loop and ignores the voltage reading produced by the HO2S.

Rich means that there is more fuel than air being taken into the combusttion chamber. The ideal A/F ratio is 14.7:1 just for reference.

Oh ok, so you got headers, and you got the federal downtubes then just extended the
O2 sensor to the second cats right, because the first ones were taken out because the federal downtubes are just pipe with no cat? and if you don't have them extended then you trip the CEL(check engine light?) which makes you run.. rich(not sure what that is but it sounds bad lol) BI-GOLLY I THINK I'M GETTIN IT!

...kinda

First set of cats are deleted by the headers with those O2 sensors (formerly plugging into the front cats) now plugging right into the headers. Second set of O2 sensors plug in further back just before the 2nd set of cats and is where your O2 sensor extensions screw in.

I keep hearing the term 'federal downtubes' but I don't know what they reference. Slang for headers?

There are no legal restrictions on headers in Canada, lots of clean air up here for me to dirty up :mocking:

Federal down tubes are made by the company Walker Exhuast but I dont know much more info on ehtem as I havent looking too much into the headers. I'll talk to a friend a work soon about where he picked his up for his X. Unless he posts on here first with the info

the 4x4 headers seem to be easy to install (reconnecting the o2 sensors that is), i want them but $495 seems a tad steep for v6 headers. did you notice a good amount of power gained with the headers?