Cutting vents - pros and cons

Did you cut your vents?

  • Yes, and I feel great about it

    Votes: 13 17.1%
  • Yes, and I am considering going back

    Votes: 0 0.0%
  • No, but I am sure will do it in the future

    Votes: 17 22.4%
  • No, cutting my own car?! are you crazy?

    Votes: 46 60.5%

  • Total voters
    76

Prozento

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Dear Civicx Members
I spent a lot of time considering to cut this huge ugly horrible disgusting black fake rear vents. I spent time reading a lot of topics about it on this forum and these are the main ones:
https://www.civicx.com/threads/cutting-opening-up-existing-fake-vents-on-front-bumper.27081/page-5
https://www.civicx.com/threads/diy-rear-bumper-fake-vent-conversion.14370/page-19
https://www.civicx.com/threads/poss...ng-mustaches-with-the-17-hatches.42357/page-3

Not only the look is far to be beautiful, there is a huge amount of dust trapped all the time on the rear bottom part of the rear bumper.

BUT...there is always must to be a "but"...

When I read all these topics I thought that Honda missed this point and there is no reason to not cut these vents...and then the 2020 generation came out with same but a little deeper vents...fake again.
Now my main question is - wont I make any damage to aerodynamics or other characteristic of my car by doing this small change? In the end, I am far to be as smart as a division of Honda engineers, so maybe they got a point? Or on other hand maybe its just some "safety" thing that they cant go over and cut them already on the factory.

Hope to hear you opinion (and sorry for my english)
Sincerely
Prozento
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MuffinMcFluffin

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According to others, cutting holes in front vents would produce more drag, whereas cutting holes in rear vents would reduce drag. Cutting the front also exposes more parts to water that you might not want to take in water, too (the only opening they currently have in the front vent is for the horn).

I'd love to do a rear vent cut myself, but to make it look best it appears that if you want the whole thing to be "open" you also have to cut into some of the bumper. I'd be taking it to a shop for that. Technically that reduces weight and creates a larger opening, which should also improve speed in the long run. I'm sure none of it would actually matter unless you're looking to improve your 0-60 time, though.

Also, most people aren't cutting holes out of the actual vents themselves. They are removing the plastic fake bit, fitting some grated/holey object into the frame of the vent piece, and then securing it with adhesion before placing it back in. If I went through this process, the only "cutting" I'd do of my vehicle would be of the bumper itself.
 

FK7 Civic Pilot

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Dear Civicx Members
I spent a lot of time considering to cut this huge ugly horrible disgusting black fake rear vents. I spent time reading a lot of topics about it on this forum and these are the main ones:

When I read all these topics I thought that Honda missed this point and there is no reason to not cut these vents...and then the 2020 generation came out with same but a little deeper vents...fake again.
Now my main question is - wont I make any damage to aerodynamics or other characteristic of my car by doing this small change? In the end, I am far to be as smart as a division of Honda engineers, so maybe they got a point? Or on other hand maybe its just some "safety" thing that they cant go over and cut them already on the factory.

Hope to hear you opinion (and sorry for my english)
Sincerely
Prozento
I cut out the rear vents about 2 years ago, and the only measurable difference anyone is going to have on a daily driver doing the legal speed limit is in terms of appearance. I’ve read wild speculation about this mod, from “ you’ll cut your quarter mile time and lose weight” on one side, to “ you’re going to poison yourself with exhaust gas, create drag, and have a dirty rear bumper” on the other side.
For me, none of those claims were true. My gas mileage remained exactly the same, my 0-60mph time remained exactly the same. My coast down distance on a measurable road I use to check aero mods remained exactly the same. Cutting out your vents isn’t going to suck exhaust fumes in the interior of the car. The rear bumper area neither stays any cleaner, or get any dirtier, than before the mod was done.
That said, I would still cut out the vents, it was a free mod, requiring just the labor involved. Everyone who’s seen it agrees the Civic looks a lot better with vents that doesn’t look fake.

The reason why Honda went the fake vent route is because for a mass produced car, there’s nothing to be gained making functional rear vents worth the added manufacturing costs over sticking on a fake garnish piece. Even the 2020 Toyota Supra is festooned with fake vents all over it, it’s just what car manufacturers do, and the majority of the car buying public accepts.

Honda Civic 10th gen Cutting vents - pros and cons 0712D1A8-58DC-43C6-83BD-3E2F80892B1E


Honda Civic 10th gen Cutting vents - pros and cons 28E4E698-4D30-4C6F-A998-1625715E2E44


Honda Civic 10th gen Cutting vents - pros and cons B90BE8C7-2A51-4D76-95EA-03A5B024A60A


Honda Civic 10th gen Cutting vents - pros and cons D071EBC6-7E0E-440B-9B97-FF9FCCEC7271


Honda Civic 10th gen Cutting vents - pros and cons 6EAB4D35-B197-45DB-A056-9D389C685F22
 
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Prozento

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I cut out the rear vents about 2 years ago, and the only measurable difference anyone is going to have on a daily driver doing the legal speed limit is in terms of appearance. I’ve read wild speculation about this mod, from “ you’ll cut your quarter mile time and lose weight” on one side, to “ you’re going to poison yourself with exhaust gas, create drag, and have a dirty rear bumper” on the other side.
For me, none of those claims were true. My gas mileage remained exactly the same, my 0-60mph time remained exactly the same. My coast down distance on a measurable road I use to check aero mods remained exactly the same. Cutting out your vents isn’t going to suck exhaust fumes in the interior of the car. The rear bumper area neither stays any cleaner, or get any dirtier, than before the mod was done.
That said, I would still cut out the vents, it was a free mod, requiring just the labor involved. Everyone who’s seen it agrees the Civic looks a lot better with vents that doesn’t look fake.

The reason why Honda went the fake vent route is because for a mass produced car, there’s nothing to be gained making functional rear vents worth the added manufacturing costs over sticking on a fake garnish piece. Even the 2020 Toyota Supra is festooned with fake vents all over it, it’s just what car manufacturers do, and the majority of the car buying public accepts.

0712D1A8-58DC-43C6-83BD-3E2F80892B1E.jpeg


28E4E698-4D30-4C6F-A998-1625715E2E44.jpeg


B90BE8C7-2A51-4D76-95EA-03A5B024A60A.jpeg


D071EBC6-7E0E-440B-9B97-FF9FCCEC7271.jpeg


6EAB4D35-B197-45DB-A056-9D389C685F22.jpeg
First of all thank you for a great reply. I agree that its diffidently looks better.
Can you please show the tools you did it with? Was it literally cutting the holes on the original fake vent or you cut all the whole hole and glued a new net?
 

COOL COUPE

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The back vents are unforgivable - that's why I would only go with the coupe. I don't mind the front at all .. honestly ... The new front makes it worse in front because the honey comb in the middle left and right is now all goofed up. So ... I like my front end even more! The 2020 lights take away from the mean look that I like with car. I will either keep this car for 12 more years or maybe get tempted by something else ... Time will tell. The 2020 wheels would prevent me from a purchase ... So I am good!
 


NonyaBisness

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I wouldn't expect much if anything other then a visual change by cutting out the rear vents but blocking off vents on the front is a favorite past time of hypermilers trying to reduce drag. Honestly I doubt it's a big change and there are aftermarket bumpers with fully open mesh vents so aside from being able to see all the parts behind the vents (like the unpainted crash bar or the piping for the intercooler) I think it just comes down to what you think looks good, remember automakers are using every trick to try to optimize mileage to fit the CAFE standards that they have to reach while still giving style to the cars to attract buyers so even small fractions of an increase in MPG might not matter to the individual they matter to the companies producing the vehicles.
 

FK7 Civic Pilot

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Honda Civic 10th gen Cutting vents - pros and cons image
First of all thank you for a great reply. I agree that its diffidently looks better.
Can you please show the tools you did it with? Was it literally cutting the holes on the original fake vent or you cut all the whole hole and glued a new net?
I used my Chinese knock-off of a Dremel rotary tool, With the small cut off wheel to cut out the section of the plastic bumper cover underneath the fake vents, and a spiral cutter to cut out the slots of the vent itself. The small files were used to dress up the edges of the vents after I finished with the rotary tool. Tedious and time consuming, I popped out the rear garnish and worked on it a little each day, depending on my patience I’d cut anywhere from maybe 12 slots to as little as two slots a day, taking my time so not to make any mistakes. I just cut out the original solid part of the honeycomb. I’ve seen where guys cut out the entire middle part and epoxy in a replacement screen, looks ok and might take less time, but would cost extra for getting the screen and epoxy, where the way I did was purely a labor only mod.
 

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I don't like your poll options. I have nothing against cutting my car, I just don't want to. It's a lot of work for negligible benefit.
 
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Prozento

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I don't like your poll options. I have nothing against cutting my car, I just don't want to. It's a lot of work for negligible benefit.
Hey. It was made just for humor reasons, no offense :). The idea was "I made it already", "Planing to do it" and something like "Never will even think about it".
 
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Prozento

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image.jpg


I used my Chinese knock-off of a Dremel rotary tool, With the small cut off wheel to cut out the section of the plastic bumper cover underneath the fake vents, and a spiral cutter to cut out the slots of the vent itself. The small files were used to dress up the edges of the vents after I finished with the rotary tool. Tedious and time consuming, I popped out the rear garnish and worked on it a little each day, depending on my patience I’d cut anywhere from maybe 12 slots to as little as two slots a day, taking my time so not to make any mistakes. I just cut out the original solid part of the honeycomb. I’ve seen where guys cut out the entire middle part and epoxy in a replacement screen, looks ok and might take less time, but would cost extra for getting the screen and epoxy, where the way I did was purely a labor only mod.
Thank you very much for the info. Look like a really time consuming work hehe. But as for me, its indeed looks good.
 


MuffinMcFluffin

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So what does it take to pop off the rear bumper pieces? I assume you don't have to remove the entire bumper to do so, would you? That doesn't seem like it would be very much worth it on an everyday basis to do, heh.
 

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So what does it take to pop off the rear bumper pieces? I assume you don't have to remove the entire bumper to do so, would you? That doesn't seem like it would be very much worth it on an everyday basis to do, heh.
If you just go with a dremel tool you probably don't even need to take the pieces off to modify them. Just be careful around the painted portions. I do like the way the above poster did it by cutting out the individual honeycomb pieces and leaving the honeycomb pattern intact. Looks dope.
 

MuffinMcFluffin

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If you just go with a dremel tool you probably don't even need to take the pieces off to modify them. Just be careful around the painted portions. I do like the way the above poster did it by cutting out the individual honeycomb pieces and leaving the honeycomb pattern intact. Looks dope.
Same, but he also claims to have cut into the plastic bumper piece inside of the vents as well. Can't really do that without popping those guys off if you need to.

Plus, when I look closely at his job, it looks like you'd want to repaint those suckers black again somehow (Plasti Dip?),
 

DoctorC

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Same, but he also claims to have cut into the plastic bumper piece inside of the vents as well. Can't really do that without popping those guys off if you need to.

Plus, when I look closely at his job, it looks like you'd want to repaint those suckers black again somehow (Plasti Dip?),
True true, you may need at least some black touch up paint. If he didn't use any plasti-dip or paint it looks very clean for a simple mod.

But I don't believe the rear bumper is too difficult to remove if the plastic vents can't be popped out on their own. Hopefully they can though.
 

FK7 Civic Pilot

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So what does it take to pop off the rear bumper pieces? I assume you don't have to remove the entire bumper to do so, would you? That doesn't seem like it would be very much worth it on an everyday basis to do, heh.
IMHO, taking the bumper off and on was the easiest part of the mod. Tools used was a T30 bit for 4 bolts, a small flat screwdriver for popping out the plastic trim fasteners and for helping to pop out the garnish piece, and a trim removal tool to separate the bumper cover from the quarter panel clips. There’s a few YouTube videos that detail how to take off the rear bumper cover, takes about 15 minutes, and much easier than trying to just pop off the garnish pieces while the bumper cover is on the car. No touch up paint from cutting the slots is required, the vent garnish is black throughout. The white flecks you might be seeing in the photos is just from my crappy android phone camera lens. I did spray the white orchid pearl body and bumper area a flat black, thought it would look better once exposed from cutting the vents, but that’s just a personal preference.
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