Xterra / Frontier 3.3L V6 headers by Doug Thorley

[SteeevO]

Getting these new headers made by Doug Thorley has been a long process that took much longer than we anticipated. From the first prototype, to ordering the materials, bending the tubes, having small parts machined, welding, and ceramic coating, all mixed in with Doug Thorley's other large projects, we finally got them done and the pre-orders have shipped. Being that the headers just arrived a few days ago, we haven't squeezed a 3.3L Super Charged truck into Doug Thorley's busy R&D department for test fitting quite yet but we're working on getting this done as soon as possible. We know there are tons of you guys asking about these for your super charged trucks and I want to get you guys taken care of as well. For those that are interested in a set of headers right now, we do have them on the shelf ready to ship and can be ordered here:  Nissan 3.3L Headers by Doug Thorley I thank you all for your patience while we pulled this project together.
-Steven Lutz

[mikeyjm1]

just a note: you said all hardware is included. I just ran around town to get the gaskets needed and fought several hours to get one side apart to realize that half of the head stud/bolts are not going to work. i would recomend that anyone preparing to put these headers on gets new gaskets and a new set of the short studs and nuts ahead of time. looks like our X is down for the weekend.

[SteeevO]

Originaly DT was going to include new gasgets but they then found out that the factory ones are metal which don't need to be replaced.

I wasn't aware of any stud issues. the headers have been installed on other xterras without issues at all.
can you elaborate?

[mikeyjm1]

three of the studs on each side are very long since part of the manifold is thicker. the long studs are not fully threaded they only have threads at either end.

[SteeevO]

What year is your truck and is it super charged?

[mikeyjm1]

no not supercharged. i did figure out that there is no egr on mine so i had to plug it. now my only problem is leaks around the bottom flanges. the oem pipes didnt have gaskets but i guess this will need them.

[SteeevO]

Strange the you didn't have gaskets from the factory there.
What year is your truck?

[mikeyjm1]

2001

[mikeyjm1]

UPDATE:
 the xterra is my wifes and she was away on business while i did battle with the truck. i did finally win. they do sound pretty cool, the truck sounds more like it looks now. i dont have a dyno budget but for "seat of the pants" it seems to bog just a bit from a start compared to the original higher back pressure but mid range and top end power seems to be decently improved. just reinforces that i need to re-gear. Chris is very happy with them.

[onewaysoldier]

Hey Steve,

      Do you know if the headers are CA Smog friendly?

[SteeevO]

Unfortunately they are not CA smog legal

[mikeyjm1]

more updates:

1. the bad. the coating on these kinda sux. the have little rust bubbles popping through all over the place.

2. THE GOOD!!! WITH STATE INSPECTION COMMING UP, I FINNALY TACKLED THE "CHECK ENGINE" LIGHT.

     I SIMPLY SOLDERED A RESISTOR IN THE BLACK WIRE IN EACH OF THE SECONDARY O2 SENSOR HARNESSES. YOU CAN DO THIS EASILY IN THE ENGINE BAY, ON TOP OF THE PASSENGER VALVE COVER. I USED WHAT I HAD ON HAND SO ONE IS A 1.13kOHM AND THE OTHER IS 1.47kOHM.
SO FAR, SO GOOD...

[mikeyjm1]

OK, I did later pop a code on the passenger side (1.47kOhm) but the driver (1.13kOhm) worked. I switched to a1kOHM that tested at 1.001 and its good. I just passed the Inspection with no faults or codes.

Now Im gonna look into getting the 2000 Xterra mid pipes. did anyone know that they fit perfectly in place of the secondary cats?

[mikeyjm1]

new update:

just popped the CEL at about 100mi since the last reset. but it passed its annual check yesterday so now i have time to perfect it. havent been back to Advance Auto to rescan but i still believe im on track.

more to come when i get further into it.

[granitex]

CEL eliminators do a really good job of taking care of the codes, They take the o2 sensors far enough out of the exhaust stream that they still pick up that there is a difference in the voltage between the two.

They can be a Pain to install but they do work.

[SteeevO]

The next shipment of these headers is due in by June 24th.
 

[mikeyjm1]

I recently found a local exhaust shop, that does mandrel bends, that can build new  midpipes with high-flow magnaflow cats. he will make proper sized pipes to make a smooth transition between the headers and the nismo y-pipe and exhaust and also move the rear o2 sensors downstream so they work correctly. the quote is $400 total.

i have moved a sensor like this before, on my old sentra se,r since the sims never seemed to work consistently.

I'll post more when this has been done.