Have any of you installed Mugen headers before? What's the best way to do it ie where do you start and what piece should be put on first etc. Are there any instructions on header install around? Thanks.

 

i've never installed MUGEN one but i have lots of experience with headers and such ..

first of.. is ur car old ?
cause the only hard part about installing a new header
is removing the stock one
ehhe

u should check out for rusted bolts on the head and the 2 spring/bolts that holds the header to the downpipe ..

though if u get mugen..u are surely having the mugen cat that go with it ?
if u do..
then it's pretty easy

first off...remove the heat shiedl on ur car
maybe use some wd40 on the header bolts if they seem rusty alot
only use 12 mm socket on header bolts. . and a 8sides one
u'll maybe have to use a 12mm key too ..

be sure to put the socket all the way on the bolt or u could strip it ..

then untighten all the header bolts..
next the oxy sensor(s) on the cat ..
i don't remember what size it is..but it should be either 14mm or 17mm
( everything on hondas is 10,12,14 or 17mm ...19mm for lugs )
use a key
if it seems to be really really hard..and u are afraid to brake it ..as all the oxy sensors always are after few years.. ur only option will be to use a blow torch and heat it up a little bit..then it will come out easy e


go under the car..
and remove the bolts that holds the cat to the piping. .
( i dont' really remember how it is ..but i think it's only 2 12mm bolts )

then check out for the gasket ..

while ur at it..u can check out ur exhuast port to see if they are clean
maybe little hand sand paper kob woul help ;p
just don't overdo it..and blow the dirt away afterward ..

then use mugen exhuast gasket.. ( i think there is a side for it.. )
assemble the header and the cat before putting them on the car..that should make it easier

then put all back reverse order

maybe there is specific mugen stuff to do too

ah and i heard that the mugen changes color if u leave **** on it when it's running..
so if u don't want some spots on it..try to wash it before turning the car ON ..

( there maybe a round gasket for the cat to the exhaust pipes too..don't forget it )

 

Thanks Jin. My car is a 98, with 22k miles, so the bolts might be stuck on there pretty well. you said to assemble the header before I install it? Will it fit into place if I do that? Also, would you recommend getting a new header gasket or can I just use the stock one again?

 

I wrote this on another board when I installed my Mugen header, hope this helps.

I started the process by spraying WD-40 on all bolts a week prior to doing the install.

Every morning for a week my car could be seen puffing white smoke on route to work. It was sorta funny to watch people starring at me in bumper to bumper traffic.

INSTALL
I started the install by trimming away the metal covering the catalytic converter as the flange on the Mugen is bigger than the stock pipe and wouldn't fit unless I 1. bent back the metal or 2. cut off the excess metal

1. I used a dermal and about 12 cutting disc's later the metal was cut.
2. I started with the 3 bolts that connect to the cat !

O2 sensor was my main concern and I wasn't gonna continue if we couldn't get the O2 off ! but with out any hassle and a 7/8th wrench the O2 sensor come really smooth.

So working our way from the cat to the block all the bolts came off one by one ! The WD-40 did it's job !

Once the header was off ! I decided to clean out the exhaust ports with some carb cleaner so that took me about 45mins to an hour. I got the exhaust ports looking like brand new !

As I was cleaning the exhaust ports I also wiped down the Mugen header with some brake cleaner. Once that was done it was time to wipe clean all the nuts and bolts to make sure there wasn't any WD-40 remaining so they didn't loosen up once installed.

3. Now came the fun part we installed the header with the new exhaust gasket from Honda. Once the header was on, we noticed that there were these 2 brackets one on each side of the header that was sorta making contact with the header ! These 2 brackets actually were there to hold up the stock exhaust manifold but with the Mugen being bigger the brackets were actually getting in the way ! At this point we decided to remove these brackets, after some carefully consideration they were removed.

4.had to pry the A-pipe onto the cat with a thick screw driver ! Once we bolted the
3 bolts there everything else just fit like a glove. The only hard part was the O-clamp that goes over the collector and the collector on the Mugen header being 2 3/8 inches the stock O-clamp was a tight and I mean very tight fit ! but once we were able to the bolt started the clamp went on pretty easy.

Once it started I watched to see if I was gonna get the "engine" light telling me I messed up my O2 sensor. I let the car run for about 10 mins and no light ! So the sensor still works and no leaks, NOW was the time for a test drive !



[Modified by Luded, 6:32 PM 9/5/2001]

 

very very nice luded....thanks. Your post will be by my side when I do the install.

 

Here a some additional information that you might find handy.

In the picture below you'll notice the O2 bung on my header is located on the side of the collector pipe just take a look at your collector pipe some Mugen headers have the bung on top of the collector pipe dead centre. Nothing really wrong with the O2 sensor being there but the wires for the sensor will make contact with the under body of the car. This might lead to some problems if there is too much vibration from the header, resulting in a faulty O2 sensor.

Secondly you can also see where I had to cut the heat shield around the cat in order to make room for the Mugen flange to fit on the cat.

Here's a picture of my Mugen header
[img]C:\WINDOWS\Personal\My Pictures\Post-1-14833-O2_sensor.jpg[/img]

Here's a picture of someone else's Mugen header (notice the O2 wires)


[img]C:\WINDOWS\Personal\My Pictures\O2 on top.jpg[/img]

 

I think my sensor area might be directly on top. What should I do to prevent from having a faulty O2 sensor?

The guy I bought them from said that the headers rub against the frame when the motor shifts. He said he filed down the frame area wher it was hitting because it was making a noise when he turned sharply or accelerated hard. have you heard of this?

 

oh, those pics you're trying to post are on your c: drive. Can you email them to me??? I want to take a look. Oh and any other mugen header install pics you have would be much appreciated too. thanks!