2017 Lx hatchback compatible with 2020 sport hatchback diffuser ????

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Zanraza03

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I also get 25mpg after my exhuast setup
My gas mileage has actually improved by 1.5mpg, for about 41-42mpg. That’s with about 90% freeway driving, and just cruising along at 65-70mph, trying to keep out of boost as much as possible. But even thrashing it, my mileage doesn’t get any worse than 32-33mpg. What were you getting before the exhaust conversion? 25mpg seems pretty bad, even if you just are doing city driving.
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FK7 Civic Pilot

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There is a lot of unknown variables on why both of you seem to be getting worse mileage. Generally speaking, a cat back exhaust on the Civic isn’t going to have much impact on the car’s performance / gas mileage since all the change is downstream of the cat and 02 sensors. In my case, I believe the gas mileage improvement is coming from reduced back pressure and possibly better exhaust scavenging, based on the long term / short term fuel trims running slightly leaner than with the OEM exhaust. But we’re talking about a 4% increase in gas mileage, not a huge change. Not sure what your fuel average was before the exhaust mod, but if you’re getting more than a 5% change in gas mileage, and assuming nothing else is different, ( driving habits, bad alignment, bad 02 sensor, new tires, under inflated tires, etc ) then I’d check to see if you have an exhaust leak somewhere, or your exhaust pipe is damaged ( sharp bend, restriction in exhaust, or significant change in the pipe diameter ) Too early for winter blend gas, but you might ask your gas station if they switched over early or something. That usually affects a 10% decrease in gas mileage. ( based on what I see when California changes to winter blend gas )
 
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Zanraza03

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There is a lot of unknown variables on why both of you seem to be getting worse mileage. Generally speaking, a cat back exhaust on the Civic isn’t going to have much impact on the car’s performance / gas mileage since all the change is downstream of the cat and 02 sensors. In my case, I believe the gas mileage improvement is coming from reduced back pressure and possibly better exhaust scavenging, based on the long term / short term fuel trims running slightly leaner than with the OEM exhaust. But we’re talking about a 4% increase in gas mileage, not a huge change. Not sure what your fuel average was before the exhaust mod, but if you’re getting more than a 5% change in gas mileage, and assuming nothing else is different, ( driving habits, bad alignment, bad 02 sensor, new tires, under inflated tires, etc ) then I’d check to see if you have an exhaust leak somewhere, or your exhaust pipe is damaged ( sharp bend, restriction in exhaust, or significant change in the pipe diameter ) Too early for winter blend gas, but you might ask your gas station if they switched over early or something. That usually affects a 10% decrease in gas mileage. ( based on what I see when California changes to winter blend gas )
Ya I’m not sure other than I don’t drive good lmao
 


ilipac

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The excess turbulent air That is coming up and through the bumper is causing my rear bumper to shake or flex at speeds in excess of 80 mph
 
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Zanraza03

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Oh , that’s weird mine doesn’t do that ? And some of my pins didn’t even match up
 

ilipac

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ilipac

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Any source on the euro finisher piece or part number yet? Spent a good time trying to find a part number with no luck.
i got rearended so that’s a no go for no lol. I’ll be using Stephen for the part. I’ll be parting my civic out in April/May
 

Rjgonzales27

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i got rearended so that’s a no go for no lol. I’ll be using Stephen for the part. I’ll be parting my civic out in April/May
Sorry to hear that, I found a thread that had the part number and source. That little trim piece is about $150-170. I’m just going to reroute my exhaust.
 

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Screenshot_20200803-182421.jpg


So this is the part. You should be able to get it at your local Honda dealer for around this price. I got mine for around $120 and picked it up because shipping is insane. You need part#26 too, it's the little cover in the middle which is a stronger plastic, otherwise the exhaust will slowly deform your bumper over time.
This is pretty late, but are these the only 2 parts necessary? Or would I have to buy the entire 2020 sport bumper?
 
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FK7 Civic Pilot

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This is pretty late, but are these the only 2 parts necessary? Or would I have to buy the entire 2020 sport bumper?
Yes, that's all you need to install the 2020 diffuser on a hatch. It won't fit if you're planning to put it on your EX-T sedan.
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