Alright, just to provide some info for the people out there..

my car is a jdm z33, and i just bought a pair of headers off ebay. the headers were $89 for the set, the shipping cost was more than the actual headers for me being in new zealand.. still a good price for a set of headers that is made out of T304 stainless.


The quality of the headers were actually better than I thought. the weldings seemed 'ok' but the joins were not polished down to smooth, who cares, you can't even see the damn thing when they're fitted anyway :P
the tubes were about 1.5mm thick, flanges on both ends were smooth enough and the set came with required gaskets and bolts/nuts for the cat flange.
I have seen a few pictures of DC/Nismo/Alphawerks headers and their flange had this carving done around the holes to make it look tidier, this set has just flat flanges.
In the middle tube, both sides got this tag welded on that says 'Edge Racing'.
When lookin inside the tubes, I was able to see some polishing done inside to get rid of the burrs and welding craps on the engine side flange, and the joins of the three tubes.


I did not bother heatwrapping them because I wasn't sure how strong this header would be even though that there aren't much of weight hanging on the header to cause them to crack but I did not want to take any risk seeking for more high temp flow. heat wrap sure will lower the engine bay temp though


And installing, I finished the left hand side (passenger side for jdm cars) today, the work was not 'hard' but very time consuming like many have said already. I am doing this on a set of jack stands, the right hand side will be done tomorrow.

the tools required so far, strong 1/4 inch or 3/8inch drive socket wrench, good 14mm long socket(header nuts, cat nuts/bolts), good 10mm socket (heat shield, intake, underbody covers and etc), swivel, few extensions, 14mm spanner/rachet. those are MUST. if you miss any of the above tools, go buy them before starting the install because you will need them.

Removed strut brace and stock airbox, then got under the car and unbolted the Y pipe from the exhaust, then cats. Instead of taking the o2 sensors out of the cat, I simply unplugged it from the harness and pull the whole thing out. then removed the heatshield bolts off the stock headers. the space is pretty limited, make sure you got a nice 10mm socket because if you round off any of these bolts by trying it with crap socket, you are screwed. I took them all off using 10mm socket with or without extensions and swivel. after undoing the bolts, I was able to take the heat shield out of the engine bay from underneath. I had to unbolt the steering column for the right hand side (drivers side for my car) so I didnt bother doing that yet.

After taking the heatshield out of the way, taking the stock header out and putting the aftermarket one in was equally time consuming. it actually took longer to work on the nuts when putting the aftermarket one because I could not use the 14mm socket on many of the nuts due to the piping being thicker. when taking the stock header off, the 14mm long socket fit on ALL of the nuts. I removed the very front and rear one from underneath the car, and the rest from above. the very front one was a bit tricky to place the long socket on but it had just enough space to work on. when putting the aftermarket header on, I had to use a spanner/rachet. the middle lower nut was a pain to tighten up because i could only turn about 1/8 a turn each time.

I read the nismo headers intall review and it was saying that the heat shields wouldnt completely come off until the headers were off, but I was able to get it out of the way fairly easily, maybe because I do not have the steering column on left hand side of the vehicle, I am not sure.

I will continue and work on the right hand side (drivers side for me, passenger side for LHD cars) tomorrow. hopefully I wont need to drain the coolant!

 

For that price you could have found someone around you that would have coated them with thermal paint. I picked up my headers off ebay also for around $200. I sent them out to be coated by JETHOT... they still look great a year and a half later with 40k on them!

Have fun...
Zquicksilver

 

alright, right hand side is done too.

I had to remove the coolant pipe because it was just too hard to get tools in place, i dont think its easy to crack those header nuts without removing the coolant pipe..

apart from the coolant hassle, the job was pretty much identical to the other side.

i read some people saying that the header gets too close to the fuel line, i sort of agree. i do not think it will ever get hot enough to melt thru the fuel line tube but if for some reason the fuel line shakes around and touch the header, it could set the car on fire I am going to get some heat shield sleeves and wrap them, just to feel safe..

I was thinking whether i should put test pipes or cats.. and went with the cats because I didnt like the rasp when I had TP fitted, made my bumper yellowy, smell gas every morning, etc etc..

my car now has ebay headers, stock cats, ebay Ypipe and fujitsubo cat back.

after finishing the install, lowered the car from jack stand (been raised up for 3 days ) and refilled the radiator with tap water. i should flush the system soon too..

started the car, and the headers were burning the stuff on them. it smoked for a few minutes, this got me worried for a sec because i thought i was seeing exhaust gas leaking after the heating up, the headers turned a bit goldy.

the exhaust notes changed a bit. it growls bit deeper from 3k rpm onwards.

powerwise, i am not too sure but it definately gives better response. i shoudl go out and measure my 80-120km acceleration in 3rd using rsm.. i was getting 3.69~3.75 constantly, so it should be able to tell if it has created any more/less horses..

so far, i am happy with the cheap headers i bought off ebay. it came with all necessary gaskets and bolts, it fit perfectly fine, looks good under the hood.

will post the 80-120km time soon..

 

You really have a great writeup. I always wish I had the presence of mind to take notes when doing work on the car, but I never do. I do take pics though. Did you do any pictures? Did you try using a torque wrench or just guessed?

 

hehe i was doing this alone, so i couldnt take any pics.. i didnt want to put wd40-full hands on my cam lol

no i did not use torque wrench at all because it was impossible to fit in the torque wrench in such a limited space.. i just tightened them upto my 'that should be enough' torque

 

Photos would make this thread more interesting.

 

Alright, just did the 80-120km test to compare.

before - 3.69-3.75 seconds
after - 3.54~3.58 seconds

so thats 0.15~0.21 seconds of difference in 80-120km acceleration.

the car only revs upto about 5700~5800rpm so the gains above that cant be shown using this 80-120km method, but 0.2seconds of difference is not bad at all especially when comparing between 3800~5800rpm only.

I am starting 3.9 gears and cusco rs lsd install tomorrow, it will be interesting to see how much it is going to improve the 80-120km time.

 

Great job but I always try to let people know that when you pay that much for a set of headers you better get ready to buy another set soon, because you get what you pay for. Since you do your own install, I will say you don't have to worry about it. If anything happens you will replace them. Most people pay somebody to do the labor, so its a better idea to buy better quality stuff. Hope everything works out for you.

 

Had a track day session and gave the car some good push, and the headers did not crack yet i dont think it will ever crack unless i bottom the car HARD or something.

it gave me nice gain in accel, i am happy with it!