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Old 09-06-2012, 07:12 PM   #1 (permalink)
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Honda Civic Remove Rear Bumper or add a belly pan?

So after weeks of procrastinating I now have a 4x8 sheet of black coroplast, and had planned on starting on the rear, as it is like a parachute, as some have said in the past.
So just looking for recommendations on whether to do the pan or just remove the entire back end all together.
At this point looks don't really matter. So I am leaning toward just removing the bumper and seeing how much it helps.

Gonna take it into the shop tomorrow to get the clutch replaced, so it probably won't happen until next week sometime.

Opinions welcome!

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Old 09-06-2012, 08:58 PM   #2 (permalink)
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IMO if you can remove the rear bumper without destroying it or its mounts I would say test it if it ends up being better u can always take coroplast and make a cover to make it look nicer
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Old 09-06-2012, 09:32 PM   #3 (permalink)
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or just remove the part that is making it "parachute" this mod is obviously not reversible but i did something similar on my old barina:


i didnt have it on long enough to see if there were any gains though
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Old 09-06-2012, 09:54 PM   #4 (permalink)
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It's not a parachute so much as a trapped cushion of air. Unless the rear bumper hangs down below the rear axle.

Do the belly pan.
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Old 09-07-2012, 02:16 PM   #5 (permalink)
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Thanks everyone for the replies. I had sometime last night, so I pulled it off, 10 screws in total I think. Unfortunately I had the day off today and did not get my regular drive in. In theory I think it'll help, but does look a bit funny.
Was also thinking about cutting up a used one, found em on eBay and locally for about $100, so I'll wait.

I'll post some pics I took with it off, with a few angles, soon.

-Dave
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Old 09-08-2012, 12:10 AM   #6 (permalink)
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rear bumper

Quote:
Originally Posted by blackcivic96 View Post
Thanks everyone for the replies. I had sometime last night, so I pulled it off, 10 screws in total I think. Unfortunately I had the day off today and did not get my regular drive in. In theory I think it'll help, but does look a bit funny.
Was also thinking about cutting up a used one, found em on eBay and locally for about $100, so I'll wait.

I'll post some pics I took with it off, with a few angles, soon.

-Dave
I've never seen HONDA do a bumper which was too low.If anything,they weren't low enough.
One way Subaru got their 1986 XT down to Cd 0.29 was to radically lower the bottom lip of the rear bumper even with the bottom of the spare tire well in the trunk(which itself was lowered even with the belly of the car).
Had they gone lower,I can see where that could lead to higher drag.
I would follow their lead.It may not be sexy,but it's very scientific.
It highly likely that removing your bumper will punish you at the pump.
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Old 09-13-2012, 01:47 PM   #7 (permalink)
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As promised here are some pics.

Rear end with bumper cover off


From the driver side


From the passenger side


And the bumper shot from the top, really more for me and my pan plans, but hopefully others will find it helpful.


I also have some more close up shots, let me know if you have interest.

-Dave
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Old 09-13-2012, 03:17 PM   #8 (permalink)
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Quote:
Originally Posted by blackcivic96 View Post
In theory I think it'll help...
What theory is that?
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Old 09-13-2012, 03:32 PM   #9 (permalink)
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Quote:
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I also have some more close up shots, let me know if you have interest.

-Dave
I happen to have shots with the bumper on, muffler off, that I took with a bellypan possibility in mind. Here they are:







james
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Old 09-13-2012, 10:19 PM   #10 (permalink)
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Leave the bumper on and add skegs like the newer Prius ...es.

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