Gaskets Gaskets Gaskets...JDM Exhaust Install

[thegame888]

I want to install my full Mugen exhaust myself.
I have the header gaskets at both ends only.

Do I need gaskets for:
Header to cat (I have donut gasket). Any other required?
Cat to B-pipe
B-pipe to muffler

http://i45.tinypic.com/2v3hv8z.jpg

Depending on if I need them, where can I get them because they're not that common at exhaust shops?
I'd prefer to buy pre-cut ones rather than making my own.

Thanks in advance for your help guys.

[Limbo]

you will need gaskets for those point for sure, otherwise you will get leaks. Usually you put gasket glue on them also, just a light coat on the gaskets.

You can get the gasket from most exhuast shops, otherwise try ebay you might find something

[thegame888]

you will need gaskets for those point for sure, otherwise you will get leaks. Usually you put gasket glue on them also, just a light coat on the gaskets.

You can get the gasket from most exhuast shops, otherwise try ebay you might find something

Cheers Limbo. But I went to a couple shops and they didn't have jdm type gaskets. Only audm ones. Regarding ebay, I'm not sure.

Plus what sort of bolts do you recommend, plain bolts or bolts with spring?

[IEVAQ8]

wats the difference with jdm gaskets???

[thegame888]

wats the difference with jdm gaskets???

They fit because they are the right shape. Kind of triangular. Otherwise no difference.

[markismaximus]

bolts with springs are only used on joints that utilise a donut style gasket. They allow necessary movement, like on the stock cat. On a normal flange joint use normal bolts, you dont want movement, at a guess an M10x30mm bolt should suit (measure the holes). I've also found using manifold cement works better than other gasket goo. Its less prone to being blown out if there isn't a perfect seal.

[markismaximus]

this ebay seller has a variety of "JDM" gaskets and may have what you're after.

http://shop.ebay.com.au/nahux/m.html?_nkw=gaskets&_sacat=0&_odkw=&_osacat=0&bkBtn=&_trksid=p3911.m270.l1313

out of interest when you went to these exhaust places did you ask for JDM gaskets? or did you ask for 2" three hole gasket? or whatever size you're after...

[90LAN]

you dont need to put crap on a quality built exhaust

you need 2 donut gaskets because there is one in the front and back

as for cat its a good fit and most times you dont need a triangle gasket

as for bolts go to super cheap to get off the bolt rotating bolt stand

if you need the mugen spring bolt set up , it is larger than a oem honda exhaust spring bolt set up
so find one that suits it from exhaust shop

note most exhaust shops dont have this size as most honda performance exhuast sizes are odd sizes
so i wouldnt try them as they dont stock
they will tell you to cut and use two bolt flange lol

[thegame888]

bolts with springs are only used on joints that utilise a donut style gasket. They allow necessary movement, like on the stock cat. On a normal flange joint use normal bolts, you dont want movement, at a guess an M10x30mm bolt should suit (measure the holes). I've also found using manifold cement works better than other gasket goo. Its less prone to being blown out if there isn't a perfect seal.

So bolts with springs only on donut style gasket. Ok...


this ebay seller has a variety of "JDM" gaskets and may have what you're after.

http://shop.ebay.com.au/nahux/m.html?_nkw=gaskets&_sacat=0&_odkw=&_osacat=0&bkBtn=&_trksid=p3911.m270.l1313

out of interest when you went to these exhaust places did you ask for JDM gaskets? or did you ask for 2" three hole gasket? or whatever size you're after...

1. I'm thinking I might get those off ebay. Unless anyone has any other suggestions/
2. I just asked for jdm gaskets.


you dont need to put crap on a quality built exhaust

you need 2 donut gaskets because there is one in the front and back

as for cat its a good fit and most times you dont need a triangle gasket

as for bolts go to super cheap to get off the bolt rotating bolt stand

if you need the mugen spring bolt set up , it is larger than a oem honda exhaust spring bolt set up
so find one that suits it from exhaust shop

note most exhaust shops dont have this size as most honda performance exhuast sizes are odd sizes
so i wouldnt try them as they dont stock
they will tell you to cut and use two bolt flange lol

Thanks 90LAN. I know about the header needing donut, but where does the donut go in the back?

Re: cutting the exhaust, fark that!!! Never!!!!

[90LAN]

where u have marked it with a 3 it also needs a spring nut too for that location

[markismaximus]

2. I just asked for jdm gaskets.

that might be part of the problem, asking for JDM gaskets. The exhaust shop would've been saying wtf is this guy talking about.

Ask for 2" three bolt hole gasket, or whatever it is and they will have it. JDM gaskets:confused:

[thegame888]

where u have marked it with a 3 it also needs a spring nut too for that location

Ahh cool. Got the 2 donut gaskets now.


that might be part of the problem, asking for JDM gaskets. The exhaust shop would've been saying wtf is this guy talking about.

Ask for 2" three bolt hole gasket, or whatever it is and they will have it. JDM gaskets:confused:

Got all my gaskets now. Cheers.

Now I just need to find spring bolts that fit the threaded holes. Hmmm.











(PS rep given to you helpful guys; may I be lucky enough to get it in return hehe)

[thegame888]

A few more questions:

How much does Honda recommend to torque down the header bolts?

What is the proper criss cross pattern to tighten?

At which joins should I apply a bit of manifold/exhaust cement.

[markismaximus]

32nm for manifold bolts, start on the center bolt and work outwards.
like the pattern below,

...6...2...3...7
8...4...1...5...9

[thegame888]

32nm for manifold bolts, start on the center bolt and work outwards.
like the pattern below,

...6...2...3...7
8...4...1...5...9

Luv ur work! :thumbsup::thumbsup::thumbsup:

[thegame888]

Who'd have thought finding screws & bolts for a mugen twinloop would be so difficult?