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JDM exhaust downpipe
Posted: Fri Aug 14, 2015 1:26 pm
by rick82
Hi
Does anyone know where I can get a JDM exhaust downpipe from? I ordered one from my local motor factors which was meant to be for the import but was too long.
They are saying the only two they supply is uk model which is 880mm flange to flange, or jap one which is 845mm. But the one off mine is measuring 820?
Posted: Fri Aug 14, 2015 1:36 pm
by wurlycorner
Is it an oem downpipe you're after?
I may have one. Will have to check the measurements since you say you're having trouble finding on that matches your car...
Posted: Fri Aug 14, 2015 5:53 pm
by rick82
I believe so, this is the one I got previous which was apparently the import spec. The top flange holes did not match up to the manifold either?
mine has split at the flexi so am thinking if I can't get one I will just buy a new flexi section and get it welded in.
Posted: Fri Aug 14, 2015 6:23 pm
by wurlycorner
Yep, that one on the left hand side is oem.
The manifolds are the same on jdm and ukdm vtecs, so the downpipe is the same length at the front (height, in that pic) so the 2 you have there are really confusing - I can't think what's going on!
The only difference between ukdm/jdm is the flange that bolts to the cat is slightly different.
The cat is then a different length (shorter on jdm) which means the mid-section of the exhaust is a different length (longer on jdm).
Your car is a JDM 4g with an H22a engine, right?
Posted: Fri Aug 14, 2015 7:01 pm
by rick82
Yeah its a H22a JDM bb4. The holes in the top flange were way out and also the pipe diameter was slightly bigger? Not sure what's going on either

Posted: Fri Aug 14, 2015 8:15 pm
by wurlycorner
Maybe it's for an ATR?
Posted: Fri Aug 14, 2015 8:46 pm
by mercutio
one looks aftermarket maybe a megan or dc sports copy the oem one is shorter at the manifold taller at the downpipe the aftermarket are the other way around
Posted: Sat Aug 15, 2015 5:57 pm
by wurlycorner
@rick82 not dug them out yet, but can see I have a choice of 3 downpipes
Where are you located?
EDIT: have dug them all out and got pics. Will upload later...
Posted: Sat Aug 15, 2015 8:22 pm
by wurlycorner
Right, loadsa pictures;

The nearest 2 (in that pic) are oem downpipes off a jdm, the furthest is an after-market downpipe off a ukdm. They are all exactly the same fitment (length/downpipe flange etc.)
They're all perfectly serviceable and complete with lambda sensors. The flexi braiding has partially come away at one end on the middle downpipe in the pic below, but that's not a problem - the flexi stainless pipe inside is what really matters and that is intact.
2 of them have grounding marks (the after-market from the UKDM and the jdm nearest in the shot below)

The jdm pipe inside won't be damaged, it's the outer heat shield covering that's been lightly scraped.
Flanges on the other end (one of the JDM's still has the cat attached at the moment);

You can see the one off the UKDM has slots rather than holes, so it should fit a JDM or UKDM cat with no problem.
FYI, length along the underneath is 880mm

Vertical is around 235mm
A few more pics of the after-market one (basically new - it was only fitted a few months before I bought the car to break and it never did any miles on the road)
So let me know if any take your fancy?
Posted: Sat Aug 15, 2015 9:33 pm
by rick82
Thanks for those pics wurly, you say the measurement underneath is 880mm and the vertical is around 225mm which has a total length if it were straight of over 1000mm. The one that's on mine has a total length of 820mm.
I will measure the vertical length and horizontal on Monday again just to compare, I'm quite confused now though.
