Disconnect hoses, throttle cables, etc. Label the hoses as to what has VAC and what has Coolant. One of them is your PVC line, which will probably be oily.

unbolt the front 10mm bolts first. Everything you can see when standing in front of car.

Then remove 2 10mm EGR bolts.

Then some bolts in the back, theres 2 brackets there with 2 holes each. not sure if yours has all 4 holes being used but they're 12mm.

 

So besides that does the 3.5 headers produce more power then the 3.0 does or are they about the same?

 

I purchased the 3.5 OBX Headers off of a guy on ebay named Sparktech I believe, paid 350 or so shipped new in box, was a good seller, quick to ship and gives you tracking number.

As for the install, I installed on my 02 SE - get yourself PBBLaster and if you have access to heat (torch) get ready to use it. I live in the Northeast, rust is a big issue up here and I stripped/broke roughly 10 bolts off my headers/heatshields/exhaust. Other then that its generally self explainitory if you have automotive knowledge.

Just some food for thought, I had read a writeup on obx headers installed on a 3.5 03 and the dumbass cut the motormount, you do not have to. The motormount I speak of is the rear (firewall side) center crossmember mount, not sure how its setup on the 3.0's but theres a slight clearance issue w/ the downpipe from there, don't stress it when you get to this part - take the time to work around it, never cut/notch a motor mount becuase you loose structual integrity.

Also, the gaskets they give you are ****...absolutly horrible. Head down to Napa and get some stock ones, they'll work just fine and are much better quality. As for o2 sensors, I highly suggest that you use all 4 (in the 3.5 it has 4 total o2 sensors), I was told that if you match the o2 sensors in both Bank 1 and Bank 2 you should be okay to run 2 o2 sims but I am planning on purchasing 4 matching ones to get them all the same and rewire them in, they are 3 wire style. The only struggle I've bene having is soldering the wires, do your best to wire them 100% matching so that way you do not have any intermdiant connections, also make sure you weather-proof them to the best of your ability, shrink wrap and electrical tape do a decent job, but there are other ways.


Just to note, I am not a pro at this I am only giving my advice from the issues I've ran into w/ my install. I have a 2002 SE w/ 110k, the car wasn't very well maintained therefore I had alot of extra work to do. Take the time to do the job right, because I know for a fact I do not want to have to struggle with it again....

Any questions feel free to pm me or email me at Maltese.Rob@gmail.com Good luck my friend.

 

Just to make sure you know this and to clarify, the two primary O2's are 3-wire and the two secondary O2's are 4-wire

 

Are you sure? Which ones are the primaries and which ones are the secondary? I'm going to be wiring up my o2's this weekend... Do I only need to run primaries?

 

The primaries are the ones that are 3-wire stock, they should have been the first ones (closes to the head) on the exhaust. You only need primaries that is correct. If you put the secondaries in you will throw O2 codes. Youre gonna need a sim for the secondaries