DIY 2012+ Si Axle Back on non-Si: DX/LX/EX R18

Nix

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So after reading and thinking that some people have run the 9th gen Si axleback on their non-si I have found that this part:

DOES NOT FIT.

2012+ Si Axle back does not fit the R18. Not direct bolt on anyway.

The 2006-2011 Si axle back does fit. I'll explain how later. For now...


How to get the 2012+ SI axle back on your R18:

First off the flange on the end is completely the wrong size.

a5xg.jpg




I had thought the possibility to drill the flange existed but as you can see that would require drilling into the area where the gasket sits, & there is not enough material to drill towards the outside either.

dv9.sized.jpg


It's not even close. So what to do?



I took both mufflers down to the local exhaust shop and had them cut the flange off the current R18 muffler and cut the flange off the new Si muffler. Then they welded the old one onto the new one. They did a pretty nice job. I gave them a lot of freedom and said "just make it work." I didn't care where they cut/welded whatever.

Here's the results:

5g95.jpg



They managed to get it right on the end and only transferred the flange.They said it was a little tricky since it was so close to the bend.

dful.jpg



Not the cleanest weld but they did it for me in an hour while I waited.

buj2.jpg



So now it should bolt right up to your R18. Reuse your old gasket and hanger. You may have to bend the tangs to get perfect fitment under the bumper. Also reuse your hanger. Thats the black rubber thing you see in the picture on the tangs.

Install is 2 bolts and a hanger. I'll try and get pics when I do this in the next couple days.

So how much did this cost??

That's the real variable.

Option1: 2012+ Si axle back:

Requires modification. You will no longer have your stock muffler.
2012+ axle back - $100-150 used
Welding - $depends on the shop you go to. They charged me 1 hour labor $86.

Total so far: $246.


Option 2: 8th gen (06-11) Si axle back:

Direct bolt on fit.
Find a 2006-2011 SI axle back. Usually $100-150.
For this to work you need a new 8th gen Si muffler gasket. About $20
Part number: 18229-S7S-003
Possibly a couple 5/8" washers to space out the spring bolts so they don't rattle.
nat3d has an 8th gen axle back on his 9th gen R18.

Total: <$200


Option 3: Borla Non-Si Axle Back:

Borla makes a direct bolt on for the 2012+ R18
Part #11828
Wesellcarparts has it. It looks nice but it is costly.
http://www.wesellcarparts.com/store/scripts/prodView.asp?idProduct=9814

Total: $400-ish!


Option 4: Megan Racing Non-Si Axle Back:

Same as the Borla.
http://www.wesellcarparts.com/store/scripts/prodView.asp?idproduct=9833

Total: $400+ Yikes!


Option 5: TSUDO cat-back system:

Yes, you can get a full cat-back tsudo for the EX/LX for less than the cost of the Borla or Megan muffler alone.
http://www.erzperformance.com/Tsudo-Honda-Civic-DX-LX-EX-2012-2013-Coupe-or-p/20-9376.htm
Total $330-ish




I think Injen has an axle back that should be available at some point but I didnt see it available yet.


Let me know if you have questions. I'll try and get the install done this weekend. Ill post the update here.
 
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Thanks Nix! This info might make it easier to sell my Si exhaust after I install my Full-Race exhaust. :D
 
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Nix if you like i can make a video for everyone to hear the 8th gen exhaust.
 
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Yes that would be great! Thanks nat3d. Also confirmation that the 8th gen bolts right up?
 
yup. direct bolt on no hassle 5 minute mod. 3 things though

1. bend the hangers. im aperently too weak to do it and left it and it will melt your bumper but its under the lip so you cant really see it.

2. it will sit close to your rear suspension. i havnt had a problem though. and ive had it on for a while (2-3 months if not a little longer)

3. i need to tighten the spring bolts and or get the washers to eliminate the rattle i get sometimes on take offs so just keep that n mind when you install yours
 
ok im kinda embarrassed to post this because that rattle is getting bad. but thats just a washer away from being fixed
 
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ok im kinda embarrassed to post this because that rattle is getting bad. but thats just a washer away from being fixed
It might be the heat sheild? My tsudo was rubbing the heat sheild and sounded pretty terrible
 
It might be the heat sheild? My tsudo was rubbing the heat sheild and sounded pretty terrible

not that i can tell. i looked and felt around and it dosent seem like its that.
 
Is it possible to get a 8th gen si exhaust and put it on an 9th gen r18. I'm not talking about the stock one but like an aftermarket axelback.
Note: I just finished putting on my buddy's old 8th gen axelback on my 9th gen r18 and it has a real nice deep tone. Not very loud though. I'm looking for something louder, but also keeps the deep tone.


Thanks for the help
 
Is it possible to get a 8th gen si exhaust and put it on an 9th gen r18. I'm not talking about the stock one but like an aftermarket axelback.
Note: I just finished putting on my buddy's old 8th gen axelback on my 9th gen r18 and it has a real nice deep tone. Not very loud though. I'm looking for something louder, but also keeps the deep tone.


Thanks for the help
one could only assume because the stock one bolts right up. i cannot confirm though.
 
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Hi everyone. A couple of questions. I acquired a 2009 Civic si axle back and attempted to install yesterday. I used penetrating oil on the bolts to try and aid in removal. When I tried to undo the first bolt it broke and some of it is still in the midpipe flange. Now, I was wondering if the nut on the flange is welded on or whether it can be removed. I purchased a new spring bolt set specified to work with my 12 Civic, however it includes a nut as well as the bolt and spring. From what I've seen the nut in the flange is welded on. Is this true? Any ideas of how to remove the piece of bolt.

Thanks
 
You could try a torch and an easy out extractor. I think they sell them pretty cheap at Harbor Freight. If not you may have to drill out the old bolt, which a trip to HB for disposable drill bits isn't a bad idea either.

Let the penetrating oil sit on it overnight. Which one did you use? 50/50 ATF and acetone is stronger than a lot of the off the shelf products.
 
I bet you'll have to use an extractor and heat like nix said. I just dealt with some bad bolts and tried the acetone and automatic transmission fluid mix. It didn't break it free with a long extension breaker bar. I used a propane torch and heated the bolt and it's broke loose easily. I think I paid like $12 for the propane torch set and igniter.
 
Thanks for the reply guys. When using a torch, would it be good to heat the bolt up and add more penetrating lubricant and then attempt to remove the bolt?

Do you guys have any experience with CRC or Loctite Freeze Off? I wonder how that would work.
 
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