5th Gen / 5.5 Gen Header Thread
i used 18 guage copper wire and just quick spliced the extension on both ends. The wiring looks kinda funny though cuz its really fat where i put heatshrink and electrical tape around the quicksplices but oh well. Im glad i didnt wait any longer though cuz the wire was almost vibrating on the header and had burn marks on it. I shouldnt have any problems w/ splicing as long as theres a good connection right?
I just received my OBX's and I am in the process of doing an engine swap.
With the one piece design of the rear header and y-pipe, anyone have a suggestion of whether it would be easier to bolt on with engine completely out, or set the engine in partially and then bolt them on?
Thanks
With the one piece design of the rear header and y-pipe, anyone have a suggestion of whether it would be easier to bolt on with engine completely out, or set the engine in partially and then bolt them on?
Thanks
Originally Posted by Ronniels
I just received my OBX's and I am in the process of doing an engine swap.
With the one piece design of the rear header and y-pipe, anyone have a suggestion of whether it would be easier to bolt on with engine completely out, or set the engine in partially and then bolt them on?
Thanks
With the one piece design of the rear header and y-pipe, anyone have a suggestion of whether it would be easier to bolt on with engine completely out, or set the engine in partially and then bolt them on?
Thanks
I would put on the manifolds before dropping in the engine, just don't tighten them all the way down.
Originally Posted by upstatemax
You can take care of your secondary o2 sensors with an o2 sim...
Pull your intake again and make sure it is installed correctly along with all Vacc lines.
Pull your intake again and make sure it is installed correctly along with all Vacc lines.
Originally Posted by OOmaxSE
I was praying that the o2 sim will take care of the secondary but it doesn't completely. If you have a faulty o2 sensor, this will trigger a P0141 code (secondary sensor heater malfunction). The o2 sim will take care of other codes relating secondaries (I believe P0138-P0140) but it doesn't tap into the heater wire, that's why the secondaries need to be plugged in still. You need to get a resistor or buy a new sensor, I'm currently in this situation... kinda steaming it out, aha.
You can sim the heater now...
Guess you have to mount it in a safe place because it gets pretty hot... But you are supposed to be able to get rid of the sensor completly after you sim the heater.
I just purchased my hotshot headers for my 03 max and it never came with written instructions. Ive searched and was unable to find what i was looking for. Can someone help me with this. Also ive decided not to go with the o2 sim and opted to weld the o2 bungs but dont know exactly where to place them. does anyone have a diagram or pic as to where they weled them. I believe its on the y pipe somewheres.
Originally Posted by 03MAXTNR
I just purchased my hotshot headers for my 03 max and it never came with written instructions. Ive searched and was unable to find what i was looking for. Can someone help me with this. Also ive decided not to go with the o2 sim and opted to weld the o2 bungs but dont know exactly where to place them. does anyone have a diagram or pic as to where they weled them. I believe its on the y pipe somewheres.
Go get a service manual for the car to learn how to swap the headers or search on this site, the instructions are on here.
The secondary o2 sims that you are not going to sim have to go behind the main cat into the B-Pipe.
If the secondary o2 sim have to go into the b-pipe then why arent they there on the stock b-pipe. Where are they located on my stock exhaust?
Originally Posted by CrucialMaxima
where do you get bungs when you want to just extend the wires??
Why would you want to extend the wires? Do you have headers?
If you do, any exhaust shop should have them.
Originally Posted by CrucialMaxima
where do you get bungs when you want to just extend the wires??
Originally Posted by upstatemax
Why would you want to extend the wires? Do you have headers?
If you do, any exhaust shop should have them.
If you do, any exhaust shop should have them.
Originally Posted by CrucialMaxima
I plan on getting some in the near future. No need to be a ****. I am just trying to find out some information.
And I was trying to get some info from you... So we can give you the info you need.
Sandy Vag FTL.
Originally Posted by CrucialMaxima
I plan on getting some in the near future. No need to be a ****. I am just trying to find out some information.
Prior to getting headers, learn as much about your car as possible. 1st thing to do when considering headers is to obtain an FSM. (Factory Service Manual).
This has well laid out diagrams of both mechanical and electrical components of the entire exhaust system. Which is something very important to a proper install and final set-up.
The question you asked can easily be found on page 1 of this thread. Or, can be seen in the FSM.
I'm sure the reason upstate asked you those questions is because of the elementary nature of your post. If you are seriously considering headers, I'd suggest doing as much research as humanly possible (searching for many hours on here and
) BEFORE asking questions on here. Basically, exhaust(pun intended) all options before asking here. Because, odds are, it's been asked and answered before. You need many hours of --->
Stock midpipe might help you with that dip in the early 5k's. Sift through this thread.
http://forums.maxima.org/showthread.php?t=376123
http://forums.maxima.org/showthread.php?t=376123
Originally Posted by vinny
hey maxspeed, was that corrected or uncorected on the dyno, also what year is your maxima, and finally what was your a/f ratio throughout the poweband?
Thats sae corrected.
heres the a/f graph for you guys.
Stock
vs
headers back after tunning.
BTW I also just got a SES today, pritty sure my MAF is bad, gettin 02 sensor cells but car feels real sligish, it happend before and i just cleanbed it, now the car feels even worse..........
Might go get it retunned.

hey max speed i see your a/f ratio is averaging around 14.5 throuout the power band, do you have any overheating problems. they set mine to around 13.4 throughout the power band, i was wondering do you have any overheating problems with your a/f ratio being set so high and is your engine a 3.5l or 3.0 they told me it would be dangerous to set the a/f ratio any higher because it could burn up the heads finally on your dino sheet was that hp at the wheels or flywheel
Originally Posted by vinny
hey max speed i see your a/f ratio is averaging around 14.5
Originally Posted by vinny
finally on your dino sheet was that hp at the wheels or flywheel
Originally Posted by vinny
they set mine to around 13.4 throughout the power band,
Originally Posted by NmexMAX
Maybe you should take another look
I'm sure he didn't take the time to remove his engine, and then strap it to an engine dyno. It was at the wheels.
Who did and with what? How did they take the readings, and from where?
I'm sure he didn't take the time to remove his engine, and then strap it to an engine dyno. It was at the wheels.
Who did and with what? How did they take the readings, and from where?
There is no way to dyno the engine itself (true chp) with out removing the engine.
I too have the same set-up and my AFR was set to 13.8 using the SAFCII Many factors come into play when tuning, especially that high. Grade of fuel, timing, IAT's, & heat range of spark plugs.
DJ248's measure power at the wheels, that's what maxspeed used to dyno.
I too have the same set-up and my AFR was set to 13.8 using the SAFCII Many factors come into play when tuning, especially that high. Grade of fuel, timing, IAT's, & heat range of spark plugs.
DJ248's measure power at the wheels, that's what maxspeed used to dyno.
Thread Starter
Joined: Apr 2004
Posts: 16,551
From: Fairfax, VA
Originally Posted by NmexMAX
There is no way to dyno the engine itself (true chp) with out removing the engine.
I too have the same set-up and my AFR was set to 13.8 using the SAFCII Many factors come into play when tuning, especially that high. Grade of fuel, timing, IAT's, & heat range of spark plugs.
DJ248's measure power at the wheels, that's what maxspeed used to dyno.
I too have the same set-up and my AFR was set to 13.8 using the SAFCII Many factors come into play when tuning, especially that high. Grade of fuel, timing, IAT's, & heat range of spark plugs.
DJ248's measure power at the wheels, that's what maxspeed used to dyno.
Also, speaking of AF tuning, theoretically, it would seem better to tune with a wideband on the dyno instead of a sniffer. This is probably more applicable to the people with a working main cat because the sniffer will pick up leaner mixtures than the wideband (assuming the wideband is bunged before the main cat, if there is one). I know a main cat affects the sniffer readings, but I'm not sure how much the difference is in terms of AFR, so maybe someone else can chime in on this.
Is the difference even significant? I would have to assume that it is.
Found some info, but not enough to satisfy:
http://forums.maxima.org/showthread....iffer+wideband
http://forums.maxima.org/showpost.ph...1&postcount=16
Yes theres is, UtsuUtsu's (?) But IMO, that's not an engine dyno. The title on the dyno sheet is deceptive (Flywheel horsepower) http://home.earthlink.net/~spchurch/...ting/id12.html
My cat isn't working, well, even it it was, my bung is upstream. In a members thread entitled tuning for newbies,(--> Credit, Kevlo911 http://forums.maxima.org/showthread.php?t=481540 ) there is enough info there to have fun with for a while.
Also I cannot remember where I read it, but there as an AFR log on a dyno with respect to both a wb and a tailsniffer and the only difference was a little lean down low (RPM). Makes sense since the exhaust velocity isn't that great, and therefore may give a lean reading.
My cat isn't working, well, even it it was, my bung is upstream. In a members thread entitled tuning for newbies,(--> Credit, Kevlo911 http://forums.maxima.org/showthread.php?t=481540 ) there is enough info there to have fun with for a while.
Also I cannot remember where I read it, but there as an AFR log on a dyno with respect to both a wb and a tailsniffer and the only difference was a little lean down low (RPM). Makes sense since the exhaust velocity isn't that great, and therefore may give a lean reading.
Thread Starter
Joined: Apr 2004
Posts: 16,551
From: Fairfax, VA
Thanks, I never actually read that whole article. 
Interesting chart there:


Interesting chart there:

One must consider the accuracy of the oxygen sensor, where it is placed in the exhaust stream, the velocity of the exhaust stream at different points in the rpm band, the tools that the tuner has at his disposal to make changes, etc. Another important factor is that most air/fuel ratios are measured via a tailpipe sniffer. This method has proven to be an excellent way of measuring the ratio, but it is not perfect at low rpm. At low rpm, an engine may not be producing enough gas to displace all of the atmospheric air in the tailpipe, and this will produce a false lean reading because of the extra oxygen - as one can see in this chart. This phenomenon is going to be more pronounced in small-bore engines with large diameter exhaust piping. Two important things must be considered when one is tuning with a tailpipe sniffer because of this phenomenon. One, a flat line across the entire rpm band will mean that the actual air/fuel ratio is too rich at low rpm. Two, a real-world driver is almost never at wide-open-throttle at such a low rpm, so the air/fuel curve at that point is something that the driver will never see. One can also see from the chart that the catalytic converter has no significant effect on the air/fuel ratio in this particular vehicle.
exhaust and y pipes
is there a recommended catback exhaust and y-pipe set-up. looking to spend no more that 2000.00 on exhuast. engine management and cold air induction. greatly appreciate suggestions. thanks paul
Originally Posted by PEC2903
is there a recommended catback exhaust and y-pipe set-up. looking to spend no more that 2000.00 on exhuast. engine management and cold air induction. greatly appreciate suggestions. thanks paul
I paid 300$ for me hotshots
about $350 for my catback
$40 for my test pipe
Intake was around $75
and a used safc II was $ 175
Plus tunning is $150.( I did it before the exhaust and once after)
Originally Posted by NmexMAX
Stay away from SAFC's. They are
and freak out 40% of the time after 6000 RPM.
I tuned for 90$/hour ( I got 5 runs)
and freak out 40% of the time after 6000 RPM.I tuned for 90$/hour ( I got 5 runs)
Originally Posted by vinny
may'be on your car but i have had no problem with mine. i have had mine tuned for a month
Believe me, it will find you.
http://forums.maxima.org/showpost.ph...6&postcount=13
Im ready to do install my headers. My friend is letting me use his new lift. So my question is what tools and size do i need to bring with me to get the job done. I want to make sure i have eveeything i need before getting half way into the project and realizing that i dont have everything. Also is it alright if i reuse all the existing gaskets. Im hoping i can install this within a day.
Originally Posted by 03MAXTNR
Im ready to do install my headers. My friend is letting me use his new lift. So my question is what tools and size do i need to bring with me to get the job done. I want to make sure i have eveeything i need before getting half way into the project and realizing that i dont have everything. Also is it alright if i reuse all the existing gaskets. Im hoping i can install this within a day.
You need i believe 12mm and 14mm deep and short sockets.
You SHOULD use new gaskets, but you can use the old ones.
The hardest part is the back header, the front you kinda have to remove the A/C line on my 2000 to get the last nut.
But pretty straight forward, good luck.
Originally Posted by 03MAXTNR
Im ready to do install my headers. My friend is letting me use his new lift. So my question is what tools and size do i need to bring with me to get the job done. I want to make sure i have eveeything i need before getting half way into the project and realizing that i dont have everything. Also is it alright if i reuse all the existing gaskets. Im hoping i can install this within a day.
I don't think anyone was stupid enough to ask it (but I will)
. Can the 3.0L headers work for the 3.5 at all? My engine is fooked and since I'm gettin it swapped, I'm gonna put headers/y-pipe, hollow out the stock cat (we don't need no stinking emissions), and a cheap wide open muffler (basically just a straight pipe haha) on her while I'm at it. Just wantin info. so I can get the cheapest crap possible (w/o being to ****ty). Thanks.
edit: I'm thinkin about the SSautochrome headers...
. Can the 3.0L headers work for the 3.5 at all? My engine is fooked and since I'm gettin it swapped, I'm gonna put headers/y-pipe, hollow out the stock cat (we don't need no stinking emissions), and a cheap wide open muffler (basically just a straight pipe haha) on her while I'm at it. Just wantin info. so I can get the cheapest crap possible (w/o being to ****ty). Thanks.edit: I'm thinkin about the SSautochrome headers...
Thread Starter
Joined: Apr 2004
Posts: 16,551
From: Fairfax, VA
Originally Posted by huffdaddy2008
Every tool youll need is either in this thread or will link you to helpful information for the install. Make sure you have a crowbar for IIRC one of the motor mount brackets. You have to bend it a little bit to get to the bolts. I reused my existing gaskets but ya its prolly better to get new ones. Have fun and good luck. 
Originally Posted by Puppetmaster
I didn't have to bend any motor mounts for my install. Once you remove the center member, you can tilt the motor backwards and will be able to reach the bolts on the rear header. Removing the IM will also help getting to the upper bolts from above.
Originally Posted by Puppetmaster
I didn't have to bend any motor mounts for my install. Once you remove the center member, you can tilt the motor backwards and will be able to reach the bolts on the rear header. Removing the IM will also help getting to the upper bolts from above.



