Full Replacement Rear Diffuser for Si sedan

Type of exhaust tips and position you prefer?


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CanadiaegeanBlue

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Hey all,

I'm not a huge fan of the HDMI port exhaust tip on the Si. Dual Tips are the easy solution, but it leaves too much blank space on both sides. Are there any aftermarket replacement diffusers currently available or incoming that would replace the OE unit?

Picture for reference, including a render that I have seen online
Si sedan rear diffuser.png


--

Here's the three replacement variants I can think of:

- Diffuser that surrounds the OE single exhaust tip (see Lamborghini Aventador picture)

aventador-s_green_063-816x544.jpg


- Diffuser that reduces the space and allows one to comfortably run dual 4" exhaust tips (see Mazda Miata picture)

242d57ac82aa3f913236bca238479df3.jpg


- Diffuser that let's you switch to a quad tip setup (see BMW M2 picture)

bmwf8710.jpg


--

Would love to see a vendor offer these full replacement options. Any insights appreciated. Thanks!



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mjdecker

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Been working on various ideas on this for some time... I'd love to get the exhaust out of those fake vents and have the diffuser contain no exhaust cutouts (though there's issues of heat on the plastic, what's behind the vents I think is a metal bumper so that will need to be cut into, ect)...

VentConcept2.jpg

I may experiment with a more aggressive diffuser but so far, I'm liking this.
 
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CanadiaegeanBlue

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First off you should take out the "sedan" part, because as a coupe owner I am highly interested as well, so it'd be great for both platforms, and secondly I think companies are going to be starting to roll out options for diffusers but its great to give some input on what we want, personally you can do a lot of different styles with our car and I like that, and most of them will look really good so it will be cool to see the unique ways people do their exhausts, hell, for example, someone has already done quad exhaust through the fake rear vents on the coupe
34956569605_e3c9e0e575_k-jpg.jpg
Have seen this one before, and I'm so-so on the idea, but that's just my personal taste. Perhaps with more pictures/angles I might like it better. Thanks for sharing :)

The R8 has a similar-looking setup, but you can see how well integrated the tip design is to fill in that space. Perhaps someone can find a tip that will fit nicely in that space!

R8 exhaust.JPG
 
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CanadiaegeanBlue

CanadiaegeanBlue

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Been working on various ideas on this for some time... I'd love to get the exhaust out of those fake vents and have the diffuser contain no exhaust cutouts (though there's issues of heat on the plastic, what's behind the vents I think is a metal bumper so that will need to be cut into, ect)...

VentConcept2.jpg

I may experiment with a more aggressive diffuser but so far, I'm liking this.
Interesting, haven't seen this so far! Unique for sure
Been working on various ideas on this for some time... I'd love to get the exhaust out of those fake vents and have the diffuser contain no exhaust cutouts (though there's issues of heat on the plastic, what's behind the vents I think is a metal bumper so that will need to be cut into, ect)...

VentConcept2.jpg

I may experiment with a more aggressive diffuser but so far, I'm liking this.
Interesting! Liking the diffuser, and waiting to see if anyone will be doing that.
 

a c i d.f l y

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First off you should take out the "sedan" part, because as a coupe owner I am highly interested as well, so it'd be great for both platforms, and secondly I think companies are going to be starting to roll out options for diffusers but its great to give some input on what we want, personally you can do a lot of different styles with our car and I like that, and most of them will look really good so it will be cool to see the unique ways people do their exhausts, hell, for example, someone has already done quad exhaust through the fake rear vents on the coupe
34956569605_e3c9e0e575_k-jpg.jpg
Am I the only one that feels the bumper port exhaust looks absolutely ridiculous? I really dig the diffuser look, but the pipes coming out of the bumper clearly contrast with the intended design of the rear end.
 
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CanadiaegeanBlue

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Am I the only on that feels the bumper port exhaust looks absolutely ridiculous? I really dig the diffuser look, but the pipes coming out of the bumper clearly contrast with the intended design of the rear end.
I agree. If it can be disguised as well as the R8 picture I shared above, then it'll be good looking.
 
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CanadiaegeanBlue

CanadiaegeanBlue

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Omg if someone comes out with a cf diffuser like that r8 with the fins up the middle and the split rectangles on each side, id buy it right now lol
The more traction this thread gets, the better the chance of that happening as vendors will take notice :)
 

a c i d.f l y

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This is the style I like best so far, if the diffuser fins were thinner and longer that'd be awesome... Quad tips isn't bad, either, just reminds me too much of an M3.

Screenshot_20180423-035912_eBay.jpg
 
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This is the style I like best so far, if the diffuser fins were thinner and longer that'd be awesome... Quad tips isn't bad, either, just reminds me too much of an M3.

Screenshot_20180423-035912_eBay.jpg
See that's a pretty good one; just need one that is Si Coupe and Sedan-specific.

The quality on that unit does look 6/10 with the fitment, and I agree diffuser fins should be narrower longer. Dual tips of Quad tip options should both be available
 

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Ok so this company called CF-Spec Carbon has some Carbon Fiber products for our 10th gens and this diffuser is like the goal of what I want for my Si Coupe and I reached out to them to see if it would fit because it didn't specify but this design (maybe more aggressive tho) is what I hope can be made by other vendors soon, the price is super steep but other options should have different prices...its the design I'm after!
s470188906567893417_p443_i1_w450.jpg
I have seen a lot of their stuff out there over the years. Pretty much everything they carry is very $$$ not sure on the quality as I have never seen any of it in person.

-R
 
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Dual Tip, Center Exit is in the lead. This is valid market research for any vendors watching the thread!

Keep the votes and comments coming :)

Exhaust Poll.JPG
 
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CanadiaegeanBlue

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Just thought about the ATS V, and realized it too has a diffuser and exhaust setup that would look good on the Si!

ATS V Rear Diffuser 1.JPG
ATS V Rear Diffuser 2.JPG
 

mjdecker

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Just thought about the ATS V, and realized it too has a diffuser and exhaust setup that would look good on the Si!

ATS V Rear Diffuser 1.JPG
ATS V Rear Diffuser 2.JPG
I especially like the idea of a backup/brake light integrated in it as well.
 
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CanadiaegeanBlue

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I like this one. Lookslike it fits in the space of the factory diffuser but extends down and fills it out.
79203_1806724689642367_3862110269886955520_n.jpg?ig_cache_key=MTUyOTE0MjYzNTg2NDA0OTE3MQ%3D%3D.2.jpg
A bit too wild for my taste, but for a show car it's not bad at all!
 

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