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Discussion Starter · #1 ·
got one side out one more bolt on the other side.
 

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Discussion Starter · #4 ·
**** yeah i did!
because as soon as you take it out and lie it on the ground.
spray bolts with wd40, wait 10 seconds and use a breaker bar to loosen the bolts. i used a crecent wrench and a hammer to get the o2 off it was easy. just at easy to put the new header on. do you know how much more time i would have wasted trying to loosen the bolts and remove the cats first. they both came out easy and went back in easy!

I would say that the most time consuming parts are getting the coolant hard pipes out. yeah every single clip was upside down and out of reach for needlenose pliers and i had to figure out a way to get them right side up just so i could simply use the needle nose pliers to pop them off.
I guess someone at the nissan factory thought this would be funny.

also half the header bolts are easy to get off and the others are a PITA.

one click per wratchet turn is rediculous.

some of them i had to use a box end wrench and on those the stud came out and those suckers take forever to get out.

and the hardest ones were the rear bolts, the last 2.

i had to use a breaker bar with extensions(beveled for a slight swivel) and a ujoint adaptor just to break it loose from underneath. the wratchet was sticking out just behind the tire.

and OMG the one on the drivers side almost stripped.....
I was using 9/16 and it was a really good fit and did not strip any of my bolts, but i quickly tried to find a tighter one and found that 14mm was a tiny bit tighter.
i went to the auto store twice today so that wasted some time right there.

as i stand right now the passenger side is on and the drivers side wil be in in the morning, its just too dark right now.

yes i have been at it all day but i'm doing it all by my self with no help.
plus i stoped a few time to get drive thru.
but yeah it was a full day.
everything came off with out breaking and things should go back together smoother. I reused my manifold gaskets because i only have 6k on my car. and if i have any coolant leaks ill take it to nissan and let them fix it. and if they complain about the headers, well honestly i bought it used with 4k on it and didnt know it had headers on it. haha.
dealership is only 2 miles away anyhow.
 

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Discussion Starter · #5 ·
here are some pics
 

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Discussion Starter · #6 ·
I have reason to believe that those who say headers dont add much power is due to the stock cats.
here is a pic of the material inside the cat. i remember the meterial used in my civic and the civic looked like a high flow compared to this. i mean the holes are twice as small.
so this is proof why people are going with test pipes and getting really good gains.
 

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Discussion Starter · #7 ·
also the stock headers(manifolds) are restrictive right at the front lips. I mean not even my factory integra manifold was this restrictive. jees. After looking at the quality of stock i was glad i was swapping the headers out.
look at the ports. the header seems to look like it has a lip but doesnt its just the sunlight. i took like 10 pics and here are the best ones i have. the pics below are the stock manifold ports which have a lip al around. the main reason for being so restrictive.
 

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Discussion Starter · #8 ·
last pics of the day!!
 

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I told you the stock headers, cats and y pipe were restrictive... :) nothing new prof. daniel

Now let's just hope the megan headers hold up and you don't have to do it all over again.


Here's the kicker... when you are done with all of this.. I suggest limping it to a dyno and checking your A/F ratio. I don't know what other mods you did, but you may have just cracked open a lean can of worms.
 

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I had headers on my car and they don't do much. Much like any n/a mod. That said, the oem extractors do look restrictive, especially when you see them in person. Still don't expect much out of headers
 

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I had headers on my car and they don't do much. Much like any n/a mod. That said, the oem extractors do look restrictive, especially when you see them in person. Still don't expect much out of headers

Did you have it tuned for the headers? ie: flash, etc.. to richen up the mixture?? Because you will net power from headers. I posted my gains in Daniels other thread about headers. Noticeable mid range improvement.
 

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Did you have it tuned for the headers? ie: flash, etc.. to richen up the mixture?? Because you will net power from headers. I posted my gains in Daniels other thread about headers. Noticeable mid range improvement.

I did the whole nine yards -
flash, test pipes, headers, intake, plenum, crank pulley, etc


Headers do very little.
 

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Headers got me 14whp and 13ft.lb of torque with stock cats, stock y pipe, arc tail section, intake.

And after that a total increase of 18 and 19 respectively WITH the ECU flash and tune + AAM y pipe and hfc.

So, I don't know, I guess that's not that much power.. but when you are still N/A it seems to be a bit better. I would be surprised to see headers not make at least 10whp.
 

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Headers got me 14whp and 13ft.lb of torque with stock cats, stock y pipe, arc tail section, intake. And 18 and 19 respectively after the ECU flash and tune + AAM y pipe and hfc.

So, I don't know, I guess that's not that much power.. but when you are still N/A it seems to be a bit better.

With my n/a setup I dyno'd at 256.9 whp on a dynojet. I didn't do a baseline and this was with everything but the ecu flash. The car actually felt more sluggish after the flash, so I would guess the pre flash numbers to be better than the post flash.


No matter what way you slice it, I figured I got about a 25whp gain out of everything I had done, obviously not doing a baseline this is only an estimate. Who wants to put up that kind of time and money into 25whp, heck, even 50 whp? What an absolute waste.

If you don't plan on going FI, throw some nice wheels on the car, lower it a bit, some tint, and leave the performance mods to no more than a catback if you must have something. The VQ is tuned decently well from the factory and it takes a lot more than simple n/a bolt ons to make any sort of real gains
 

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With my n/a setup I dyno'd at 256.9 whp on a dynojet. I didn't do a baseline and this was with everything but the ecu flash. The car actually felt more sluggish after the flash, so I would guess the pre flash numbers to be better than the post flash.

No matter what way you slice it, I figured I got about a 25whp gain out of everything I had done, obviously not doing a baseline this is only an estimate. Who wants to put up that kind of time and money into 25whp, heck, even 50 whp? What an absolute waste.
I agree with you about how much power you made tuning it how you did. I also picked up 25-30whp. True, it's not a lot.. But it depends on what you are comparing it to.

I don't believe that has anything to do with headers not making power. N/A tuning won't make you a ton of power, sure. Esp. when you compare FI. BUT, 25-30whp bolted on WITHOUT touching the heads , is pretty **** respectable. Considering the state of tune from Nissan.

I actually did a baseline before and after to provide data to Strup. So just saying headers don't make power, isn't true. They do make power. But it's along the same scale as NA tuning the Z. Small gains. But gains none the less.

I don't get how the car felt more sluggish. Did you see the a/f ratio after the tune? Was it bad? I could notice the difference after tuning. It was MUCH more responsive. :dunno:

It may not be "worth" the money.. but that is all relative. Daniel paid like $200 for the headers, so if they make 10whp at best, that's a deal. You can spend money elsewhere and make more power if you go with any FI. But, there's nothing wrong with trying to tune and keep it NA. There is still untapped potential here. Japanese tuners are now doing 340ps (which is about = to our brake horsepower rating) That's a descent amount of power over stock without a supercharger or turbo. It's just different than what everybody is doing. Because everybody wants a turbo charger or supercharger... There are very few that stay NA and set the pace.
 

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I agree with you about how much power you made tuning it how you did. I also picked up 25-30whp. True, it's not a lot.. But it depends on what you are comparing it to.

I don't believe that has anything to do with headers not making power. N/A tuning won't make you a ton of power, sure. Esp. when you compare FI. BUT, 25-30whp bolted on WITHOUT touching the heads , is pretty **** respectable. Considering the state of tune from Nissan.

I actually did a baseline before and after to provide data to Strup. So just saying headers don't make power, isn't true. They do make power. But it's along the same scale as NA tuning the Z. Small gains. But gains none the less.

I don't get how the car felt more sluggish. Did you see the a/f ratio after the tune? Was it bad? I could notice the difference after tuning. It was MUCH more responsive. :dunno:

It may not be "worth" the money.. but that is all relative. Daniel paid like $200 for the headers, so if they make 10whp at best, that's a deal. You can spend money elsewhere and make more power if you go with any FI. But, there's nothing wrong with trying to tune and keep it NA. There is still untapped potential here. Japanese tuners are now doing 340ps (which is about = to our brake horsepower rating) That's a descent amount of power over stock without a supercharger or turbo. It's just different than what everybody is doing. Because everybody wants a turbo charger or supercharger... There are very few that stay NA and set the pace.
The AFR before the flash was decently lean. TS supposedly riched up the the AFR and added some timing in up top. I had noticable tq loss down low, but the car did pull a bit harder above 5000 rpms. I never did another dyno, because it didn't seem worth it, and afterall, they're only numbers. I could care less if my car dyno'd at 200whp, if it pulled like I wanted/expected it to after the time and money I threw at it. It really was a disappoint IMO and a complete waste of my time. I lost little on the parts as I was able to sell those that didn't jive with my TT setup.

I only paid around 200 + coating for my headers which were the equivalent of strup, DC, alpha werks, megan, etc. I even installed them myself, so with a couple hundred bucks + my time I still say it isn't worth it. Heck, if I paid nothing for the headers and I merely had to install them myself, it still isn't worth it IMO.

For the time and money invested, you just don't get the returns modding the Z with n/a bolt ons like headers and exhaust.

If I did it all over again and had no plans on FI, I would do the followign:
1.) crank pulley
2.) lightened clutch/flywheel
3.)3.9 final drive
4.) Exhaust, including test pipes - stictly for the sound
4.5.)maybe a plenum or spacer

No headers, no intake, no ecu flash
 

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**** yeah i did!
because as soon as you take it out and lie it on the ground.
spray bolts with wd40, wait 10 seconds and use a breaker bar to loosen the bolts. i used a crecent wrench and a hammer to get the o2 off it was easy. just at easy to put the new header on. do you know how much more time i would have wasted trying to loosen the bolts and remove the cats first. they both came out easy and went back in easy!
I see. . .

Obviously the how to's are NOT being used.

Cat bolts are removed from the engine bay very quick & easy (2 of 3)
3rd is done from the bottom, but you're looking at it anyway.

22mm is the size of the O2 Sensor. Have both Long & Short handled wrenches for this as it will need to be checked on occasion.

http://www.350z-tech.com/zwiki/Tutorial:Header_Installation

Congrats on the install - could have saved yourself some agony that's all.
 

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If I did it all over again and had no plans on FI, I would do the followign:
1.) crank pulley
2.) lightened clutch/flywheel
3.)3.9 final drive
4.) Exhaust, including test pipes - stictly for the sound
4.5.)maybe a plenum or spacer

No headers, no intake, no ecu flash

Thanks for the nice reply , Zivman
 

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Discussion Starter · #20 ·
Honestly the bolts that mated the cat to the header were to **** tight.
I only broke one loose. So i ended up doing it on the ground.
I just want these **** headers in the car.
I did look at the wiki install and two others because i was looking for more pictures.
does wiki mention removing the alternator bracket to get to the front bolt on the passenger side, because it really needs to come off.

Yes i know these bolt ons dont make that much power, and honestly they dont make that much on any car. unless the manufacturer was really cheap on that part.

and yes when i get all of these bolt ons and only get my 25-30 i will be getting everything the enging can put out STOCK!!
yeas the motor is still STOCK!!
In order to get more power headwork and cams are needed.

I'm going to leave the head alone and get cams and final gear ratio later on.
I will choose my cams carefully.
I want as much power as possible with out having to change anything else.
also albertos car on this forum has the 287hp motor and he has his ECU modified so the redline is at 7200rpm and he has not thrown a rod or spun a bearing yet. so there are some options out there.
I don't want to go FI.
here is my list of what ive done and what i plan on doing.
K&N drop in
Megan headers.
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later on
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y pipe
plenum spacer
cams(not sure which ones)
ECU flash.
final gear mod (maybe)
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the cams will be serious money so i will have to choose wisley.

I just might go NOS again.
had a 80 shot direct port on my integra that i used for over 2 years and never had any problems with reliability.
It's like forced induction exept you use it when you want to, too bad there are not alot of people using this on the Z i would like feedback on this.

well i have to put coolant in the car, button everything up and clean out the garage.

I didn't think this would end up in a debate.

Are there any high flow cats out there that have a lifetime warranty.
Iv'e had bad experiences with them especially random technology because the material comes loose inside.

one day in my civic it started bogging down for like a week and i was sick of it so i nailed it and it struggled and then the material shot right through my exhaust and hit the car behind me on the bumper.

when i had the motor rebuilt my buddy salem told me "yeah it burned up, look its completely hollowed out".

I dont want this problem.

Test pipes are sounding pretty good right now.

hey ills have anyone on this forum have any problems passing smog?

well i have to get back to work ill chat with you guys later.
 
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