The Nissan Club banner

QR25DE Header and Pulley Install

101K views 123 replies 52 participants last post by  MarkSpecV 
#1 ·
2.5 Altima Header Install


Keywords: QR25 QR25DE Hotshot SSautochrome XS Stillen Manifold Removal Pre-cat
Applicable to any 4-1 header, or similar header without a downpipe included.

Estimated Time for Install: 2-4 Hours

Pictures and install performed on ’05 Altima AT with SSAutochrome/XS Header.

Tools I used:

Set of Allen Wrenches (preferably metric, though I used US)
½” and 3/8” Ratchet
Ratchet Extensions
Wrenches & Sockets (both ½ & 3/8, deep and shallow): 10, 12, 14, & 17mm
If possible, air ratchet and impact are useful.

The stock setup:


Start by removing the engine cover. Using an Allen wrench, remove the four bolts on the engine cover:


Then remove the heatshield by removing the four 10mm bolts, two near the top, and two on the lower part of the manifold.


There are five bolts on the manifold. In order to access all the bolts, the alternator must first be removed.



Start by removing the two 10mm bolts on the overflow bottle. Move the bottle out of the way. Then remove the 10mm nut on the front of the IPDM (the black box). Lift the IPDM out of the bracket and move it out of the way. Next, remove the IPDM bracket by removing the 2-12mm bolts in the bottom of the bracket. Remove the bracket and put it aside.



In order to remove the alternator, you must remove the drive belt. I suggest having a piece of string or wire in order to tie the belt aside and keep tension on the other pulleys (eliminating the need to put the belt back on all the pulleys). To remove the belt, use a 14mm wrench to turn the tensioner clockwise (“tightening”). Use a small bar, ie. a drill bit, a bolt, etc., lock the tensioner in place by placing the ‘bar’ through the holes in the block and tensioner, as pictured:



Next remove the alternator by removing the two-14mm bolts, one on the top, and the other on the bottom near the block. Also, remove the black wire retainer to give the alternator more freedom to move. You may have to work the alternator a bit to get it to come off. By working the alternator back and forth, it will eventually come free. Beware, it may take some effort to get off. Set the alternator aside, no need to completely remove.



Next, remove the 5-14mm nuts from the stock manifold. Start from the outside, loosening toward the center. If numbered from left to right: 1, 5, 2, 4, 3



You may have to use a large breaker bar, or another large wrench to get enough torque to turn the nuts.

 
See less See more
10
#2 · (Edited)
Header Install Continued...

Next, remove the O2 sensors from the manifold. I believe they are 17 or 19mm, but cannot confirm. (’05-06s only have one on the upper portion of the manifold, 02-04 have two)



Now, you must remove the bolts from the flange of the manifold. Gain access by jacking the car up from the front, remember to use jackstands to properly support the car.

Crawl under and locate the two bolts with springs. These are special bolts, threaded on each end, with a stud in the middle. Remove the bolts using a 14mm deep socket. Also remove the bolt just to the side of these, connecting a bracket to the manifold.



Remove the manifold by carefully lifting it out of the engine bay.





Prepare the new header by replacing the lower “donut” gasket, near the flange. Either use a new gasket, or re-use the one from the stock manifold. (Not actual gasket)



Place the manifold gasket from the header onto the bolts on the block. Now, carefully lower the header into the engine bay, and place it into the lower pipe. Another jack (stock) is useful to support the lower pipe to properly position the header to insure a proper seal.



Insure the lower seal is properly placed into the flange connection. Replace the two bolts with springs. In my case, the thread pattern from the stock manifold did not match the header. So I had to purchase new bolts and washers. They’re M10x1.25x60mm (confirm with your own). Be sure not to overtighten the bolts and overstress the springs. Be sure to tighten the bolts evenly per side to insure you have no exhaust leaks.



Place the header flange onto the bolts set in the engine block. Replace the nuts. Tighten, starting with the upper right (looking at front of car), lower middle, upper left, outer right, outer left. Torque to 29-32 ft-lb. Be sure to re-torque the two upper bolts after finishing the first sequence.

 
#3 · (Edited)
Header Install continued...

Replace the O2 sensors in the spaces provided in the header, using Anti-seize on the threads. DO NOT OVERTIGHTEN! The upper O2 sensor can be replaced directly into the header. The second sensor requires either an O2 spacer, or Sim to avoid the SES light. For ‘05+ it is recommended to use two O2 spacers. The Sim will not work for '05+.
(My ‘05s second sensor was located under the car, after the flex pipe. Other models it may be located on the lower portion of the manifold)











To complete the install, replace the alternator into position. Replace and tighten the bolts, including the wire retainer. Place the belt on the alternator pulley and insure it’s properly positioned on the other pulleys. Using the 14mm wrench, remove the “bar” used to retain the tensioner and release the tensioner. Replace the IPDM bracket, and IPDM. Then replace the overflow bottle and tighten the bolts. Finally, replace the engine cover and the four Allen bolts holding it down.

Finished product:



Congratulations. Insure the belt is properly placed, and all sensors are connected and in place. Crank the car and check for exhaust leaks, and any other anomalies. Enjoy your new header and gains!

All Comments Welcomed.
LSUtigerME
 
#4 · (Edited)
Pulley Install...

2.5 Altima UR Pulley Install (Auto)

Keywords: Underdrive Crank Lightened

Estimated Time for Install: 30 minutes

Install performed on ’05 Altima 2.5 AT.

Tools:

Jack
Lugwrench
19mm Socket
Pulley Puller
Air Impact
Flathead Screwdriver
10mm Wrench
Large Screwdriver

Start by jacking up the passenger side front wheel. Remove the wheel and set aside. Remove the plastic cover near the front of the wheel well by removing the three plastic clips, and one 10mm bolt. This should expose the crank pulley.





Next, remove the drive belt. To remove the belt, use a 14mm wrench to turn the tensioner clockwise (“tightening”). Use a small bar, ie. a drill bit, a bolt, etc., lock the tensioner in place by placing the ‘bar’ through the holes in the block and tensioner, as pictured:



Next, using the air impact, or a large breaker bar, LOOSEN the 19mm bolt holding the pulley in place. On manuals, have a friend place the car in 5th gear and hold the brakes while you turn the bolt. In autos, insert a large screwdriver through the slots in the pulley and hold it against a piece on the block, preventing the pulley from turning. Of course, if a pulley holding device is available, use it. The bolt holes are 6mmx1.0.
(Image courtesy of Nissan Performance Mag)



Do not remove the crank bolt. It is used by the pulley puller. There are several options for pullers.

The most suitable is a harmonic balancer puller (NO, our pulley is NOT a harmonic balancer). The stock (and UR) has two bolt holes in it, used by the HB puller to pull the pulley off the shaft. To use it, simply follow the instructions included. They’re also available for rent from Autozone.

The second option, used here and by me, is a claw-type puller. The stock pulley does not have much of a lip on it to grasp, but enough is there to pull it off (mine came off almost by hand). Simply position the center bolt point on the crank bolt and the “arms” around the pulley, grasping the small lip. Turn the center bolt until the pulley comes loose.
(Image courtesy of Nissan Performance Mag)



Remove the crank bolt and pulley. There will be a small amount of oil from the front seal, this is normal. Avoid getting any on the engine belt.



Apply a small amount of anti-seize to the inner portion of the new crank pulley. Also, a small amount of oil is recommended to be applied to the inner portion of the pulley (not where the shaft goes) to help lubricate the front seal. Next, position it so that the small notch on the crankshaft lines up with the notch in the new pulley. Lightly tap the new pulley into position.

Replace the crank bolt, and torque to 30-34 ft-lb. Use a large screwdriver to hold the pulley in position while you torque. Using a marker, place a small mark on the pulley next to a line on the washer on the crank bolt. Holding the pulley still, turn the bolt until the next mark on the bolt meets the line on the pulley (approximately 60º).



Replace the belt, the plastic cover, and wheel. Insure the belt is positioned correctly on all pulleys, and remove the “bar” from tensioner and release tension on the belt.

Congratulations. Check to make sure belt is positioned properly, and enjoy your new pulley.

LSUtigerME
Additional info and thanks to Nissan Performance Mag, SpecV install.
 
#5 ·
Wow nice write-up!! Sticky material! I thought you took off your headers?
 
#6 ·
I did. I had a horrible exhaust leak. I wanted to fix that, and since you guys didn't really seem interested in buying, I decided to try again. Much, much better without the leak (these pictures are from first install, you can see how tight the flange connection is w/o the "donut").

Figured I'd try the pulley too. :D
 
#10 ·
No comment on the gains right now. It's a little noisier than before. I haven't really pushed it high in the rpms, so I don't know for sure. It seems a little bit more responsive, but that's it. I'm going to give it some time before I say.
 
#11 ·
faq plz
 
#12 ·
LSUtigerME said:
No comment on the gains right now. It's a little noisier than before. I haven't really pushed it high in the rpms, so I don't know for sure. It seems a little bit more responsive, but that's it. I'm going to give it some time before I say.

Yea someone once said that the noise of the headers installed sounded like shit. I heard the video and it did. But then again that could be video quality.
 
#14 ·
Excellent Write-up and great pictures. Welcome to the Header/UDP club :).

FAQ FTW
 
#16 ·
wow... that's like a professional install guide. excellent writeup... you should sell them to xs :p
 
#17 ·
mikethemike said:
Yea someone once said that the noise of the headers installed sounded like shit. I heard the video and it did. But then again that could be video quality.
yup thatd be me, but i have an 18" resonator so i really couldnt expect much, but good news, i have on the floor behind my a 27" magnaflow waiting to be installed... we'll see what happens, nice write up, i wish i had this when i tried to instal it!
 
#21 ·
Congrats LSU on the install, i dont have a pulley yet so this might help in the future. Btw if you want, i can get a clip of my ehxuast (altho be it loud when not cruising and while driving on continuous high speeds) it sounds nice and throaty. However i have no cats, and running 2 of the biggest magnaflow resonators available with it.

I'll get some better clips of it 2morro or so.
 
#23 · (Edited)
I've gotten used to it. It definitely has some pull in the upper rpms. The sound isn't bad, but I haven't gotten to really hear it from outside the car. It's by no way obnoxious, but I'm not real sure what to characterize it since I only hear it from the inside. I don't think it sounds rice, so that's really my main concern.

It has a few frequencies where it vibrates something in the cabin, but I don't know what it is. It isn't bad, just a split second where something will rattle (like the rearview) then it smoothes out.

It's worth it. Easy install, not real expensive, and you get some nice gains. MPG went down, but I put my foot into it a lot more too.

As for the pulley, waste of money. It's easy to install, but at over $100, it's not really worth it.

EDIT: I tried to get some sound clips, but my camera wasn't really picking it up. I might borrow my gf's to see if it does any better. Or just splurge and buy a good video camera.
 
#24 ·
Wow. Great job. By the way, that header used to be mine. lol. I heard the pulley is a waste of money too. I start to feel like we waste so much money on performance parts that don't perform. I'm just gonna save up money and upgrade to a turbo instead of wasting on all of these parts. However, the look and the sound system of the car is not a waste of money.
 
#26 ·
I have the same thing, but I have a horrible sound coming from the exhaust that has just developed. It sounds like a bad exhaust leak. Im guessing it is that 'donut' gasket. I didn't have one, I didn't notice one that should have been there. I bet that it where the noise is coming from, because I only hear it if I get on it. I need to replace that here when I get the time. Good write up. The biggest pain is the alternator.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top