I've looked all around the how to section and can't find a write up on header insalls of any brand. Does anybody have a write up on this.

 

There are a few memebrs out there that do have write-ups & how tos.

 

I have this saved from one of the threads/writeups. Have fun...


Alright here is the deal, remove the radiator fans off the radiator- should be just secured with 2 10mm bolts on top and 2 on the bottom of the car. Remove the lower splash shields. Remove the motor mount bolts- that go through the motor mounts and engine mount bracket. Then remove the cross member. After that remove your 02 sensors using a 22mm wrench or a special O2 sensor socket, then remove the whole ypipe off the car. Proceed to remove the front exhaust manifold, you will need to slightly move the AC line in order to get at the left exhaust manifold stud/bolt thats all the way to the left top corner of the manifold. If you have the stock precat on the front manifold (fed spec 3.0Ls do not have it) then you might wanna remove the 4 10mm bolts that hold the shield onto the precat, and then get a 12mm THINWALL 3/8" drive socket and 14" long 3/8" drive extension to break the bolts loose from the manifold- you are removing the front precat off the exhaust manifold. After that you will be able to remove the manifold with easse. I found that if you remove the motor mount bracket off the block you do NOT have to remove the precat, it all depends on how you wanna do the job. As far as the rear manifold- jack up the motor so that instead of it sitting in the engine bay like this IIIII it will be sitting in the engine bay like this ///// - this will basically pivot the engine so that the rear cylinder head exhaust manifold bolts are more accessible. Remove the REAR engine mount bracket off the block, the 2 top 14mm bolts are impossible to get at cause there is a metal support brace inside the motor mount bracket that is in the way of the bolts. What I did was use a long pry bar and bend that support brace so that I can get my socket and 14mm rachet on those bolts, then remove the lower bolts off the bracket and you are free to do the manifold bolts. There are only 4 bolts holding the engine mount bracket to the block. After that you can go ahead and use a swivel 14mm socket to remove exhaust manifold bolts and remove the rear precat. I reused my factory exhaust manifold gaskets on the headers- they are metal and will not leak. Install the new headers on the heads HAND tight, so that you can move them around on the exhaust manifold studs, then you need to bolt the Ypipe to the manifolds. After that tighten the exhaust manifold studs tight as ***** and tighten the Ypipe. If you tighten the manifolds tight as he11 1st and then try to install the Ypipe you will not be able to install the Ypipe cause the holes for the exhaust manifold studs are big enough so that when U install the headers your flanges for the Ypipe will be way off. After you install the headers basically install your 02 sensors, install 02 simulator for the rear O2 sensors ( don't bother extending the wires most people get check engine lights from added resistance of the lenghtened 02 sensor wires that throw off the 02 readings).

NOTE- any factory bolt you will try to remove- SPRAY down with *PB BLASTER* it works alot better than WD40 as a penetrating fluid.

It took me 2 hours to do my headers, with a oil change and evacutating the AC system plus removing the high side line off the compressor- as the primary 02 sensor hits the AC compressor and line on the 3.0L with HS headers.

I could do a 3.0L header install in bout a hour now... 8 hours is highway robbery. Take it from someone who rebuilds his own trannies and engines. I don't let ANYONE touch my ride.

 

My sincere apologies for not citing and crediting the originator was for it, I did not write that down...

 

But he has a 3.5L ...

 

So true....i can't understand why people say it take so long, guess they don't have the proper know how or the proper tools. Removing clogged precats off my 3.5 took exactly 1 hour to do(getting them off and reinstalled),and i figure removal of the exhaut manifolds would take another 20-30 minutes max....

8 hours is just rediculious to install headers!

 

So, 1.5 hrs for a header install ... ?

 

If you smoke rocks.....

At a full mechanics shop with a lift and proper tools, 4hrs

In your driveway, by yourself, 8hrs

"" "" with friends, 6hrs

 

It was Mike's (BlackbirdVQ) write-up.

 

I was referring to this post ...

 

BTW, just to clarify, I pasted the entire post I had saved, none of those notes and comments within the post #3 are mine

I never did the installation myself nor I foresee myself doing in any near future... I just had it saved in case one day I change my mind...

 

Daily Driver, I am in orlando. If you can get the car up and remove the precats in 30 minutes without using a lift and air tools, I will give you my headers.

 

Hm, that's a decent offer. Wish I lived closer ;-)

Jokes aside, on my 2K, when I did the Y-pipe, it took about an hour to install it using a full size hoist, power tools and torch for two of us...

 

Doing headers is a PITA... Done many of them on other V6 cars and I do not assume it will be any easier on Max, hence my abstanance from it for now...

 

i had a certified mechanic install my headers/y-pipe (cali spec)....took 11 hours. the only extra time in there was while we looked up what to do with the 2 extra O2 sensors that did not fit into the y-pipe. had we known what to do with those, i would say it's more like a 8 - 9 hour install.

 

Oops i meant to say two hours for unstall and install....i just caught that myself. Give yourself another hour to get out the metal subsubtrate.

But all in all installing headers will not take 8 hours. Oh i removed my precats without a lift, used jack stands to hold my car up, and i did use air tools. But hey you can't fault me for having proper tools! LOL!


Oh and my pops assisted too... so ok maybe it would take a little longer by yourself.

 

All Data says it takes like 9hrs. I was hoping to do it in about halfe that time. I have the resources because I manage an auto shop.

I mainly just want to know of any problems people ran into other than rust.

 

What did you do about the O2 sensors for the rear? I just got back my car from infiniti for warranty work and one of the technicians (who is also an enthusiast) said the shop that I took my car to for the header install last year, did not plug up the correct O2 sensors for the front. I knew that they couldn't plug up all of the sensors (CEL light for about half a year) and I never bothered to check on my car. From what the technician said, I actually have one of the rear O2 sensors plugged into front (idiot). Anyway, the technician from infiniti said that my front O2 sensors can't reach far enough to plug up correctly. He also said I am losing power for not having the correct ones plugged in for the front. Is this true? IF SO, how did you guys get your front o2 sensors to plug in? What about the rears?

 

Didn't run into any rust that caused me any problems when removing my clogged precats 4 months ago...i don't think i will run into any when doing my header install in the near future....everycar is diffrent.

 

lee135 - i bought that ebay header set which had 3 bungs total in it. we took the two pre-cat O2 sensors and put them into the two closest bungs (we didn't have any problems with them reaching), then we welded the last bung closed. the two post-cat O2 sensors are just zip-tied between my headlight and battery. since they are supposed to detect nothing (a zero voltage which represents everything the cats removed), it works fine to have them just sitting in the engine bay. i've never had a CEL code either. hope that helps.

 

Okay, so still sorta on the same topic. I need to know who in the Tri State Area will install headers for me? Preferably at a decent price. My car is a daily driver, so I cant afford to have it off the road for long. Any suggestions, let me know!

 

Maybe try posting this question in the regional forums? Might get better answers there....

 

are you running cattman headers? if so, the stock primary o2 sensor doesnt have enuff wire to reach the o2 bungs for the cattman headers...when I installed mine, my wires had to be extended....the stock wire length isnt long enough for cattman headers...

 

The write up is mine.

I can do headers on a Maxima in bout 2 hours without a problem. Having done a few of them I think I have the install down. Most mechanics have no clue bout stuff like that and even at my shop some people take 8 hours or so to do a stupid clutch on a Integra. Or the mechanics who are installin em are saying it took sooo long so they can charge U up da azz for the install but didn't take near as long. They park the car outside and tell U its a long time operation.

My 02 sensor wires on the primary 02s where long enough to reach the bungs on the HS headers. I have my front header priamary 02 bung rewelded as the 02 sensor was hitting the AC compressor, so it was eighter NO AC and headers, or no headers and AC.

 

Thanks Puppet.

Will do

 

Steve

Any welding required when you move the o2 sensors? Or is it purely wire extension?

 

How much horsepower would headers give ur car?

 

Depends on the design, and what other mods you have. Headers alone without intake or catback will probably give you 10whp at most. If you have a full catback and intake, you are likely to see almost 20-25whp.

 

As mentioned in the write-up above, you could also extend the wires or get simulators...

 

There are many threads on this and answers are 5 and 5.5 gen specific...

 

Steven88 - Thanks for responding. I do have cattman headers, and one of the front O2 sensor (blue connector and wire) is not plugged in at all (idiots!!!!). I am going to a custom fab shop this weekend to get that fixed. My question to you is, am I losing any horsepower with my O2 sensors not being installed correctly? AND are you still receiving a CEL even after extending the wires? The reason why I am asking is because I just bought a Apexi SAFC-2 and I want to be running perfect before I hook the SAFC-2 up and tune it.

 

I don't think so. Nmexmax dynoed at 233 whp with headers, POP charger intake, and stock cat-back and Fezzik dynoed at 235 whp with headers, Injen intake, and stock cat-back... so that's already 20-30 whp over stock. Both were untuned as well.

http://forums.maxima.org/showthread.php?t=341501

http://forums.maxima.org/showthread.php?t=411340

 

by untuned, you mean they are not using safc, just the stock ecu?
if that's the case, those are impressive numbers, especially with stock exhaust.

 

Yes, I meant with no AF tuning/adjustments of any kind...

 

you know whats weird....I had both blue connectors (primary o2) disconnected and drove around like that for awhile...dont ask why...but lets just say I needed to do some testing...I went through one tankful with those primaries disconnected....and gas mileage, and engine performance felt nearly the same as with them plugged in...

im thinking with them disconnected, the engine is running open loop mode (rich) the whole time....and since the headers makes the engine run lean, disconnecting them will make it rich and bring it back to a stoich mixture...

just ask nmexmax...hes putting down 233whp with no o2 sensors being connected...and he banks the **** out of vdub r32s and WRXs

 

just extend the wires...no need to move the o2 bungs...its way harder to move the bungs, when u can just add some wire to the o2s....

 

I have 4 02 sensors 2 have light blue plugs, 1 has dark blue plug, and the other has a Green plug. One of the light blue connectors is at the rr corner of the engine. Wich 2 are inportant and wich 2 do I want to simulate?

 

cardomain.com/id/morgan006 page 6. writeup with pics

 

thanks but I already read that and already installed my headers. this did not speak of O2 sensors at all though. The question was wich of the 4 O2 sensors need to be plugged in, Lt Blue, Lt Blue, Drk Blue, Green? And wich ones do I simulate?