Go Back   EcoModder Forum > EcoModding > EcoModding Central
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 09-27-2013, 04:30 PM   #1 (permalink)
Certified Duct Tape Tech.
 
swoody's Avatar
 
Join Date: Feb 2008
Location: Chicago, USA
Posts: 76

Slow Ride - '00 Honda Civic DX
90 day: 46.32 mpg (US)
Thanks: 0
Thanked 0 Times in 0 Posts
Question Exhaust Choices and Mileage

Hello, world!

So it's been some time since I've been around these parts. I have been cycling the past 5 years, and am just now starting to use a car again. I currently have a 2000 Honda Civic, that will become my daily driver (former best in this same car was 50mpg).

So I noticed my exhaust has a pretty bad leak, just in front of the muffler where it attaches to the exhaust pipe. I was going to look into getting this fixed, but wanted to weigh my options first to see if there may be any difference to be gained here in terms of mileage. I basically have three paths to go here, and was hoping to gain some insight or discussion from the community.

My first thought was to purchase a cheap, aftermarket cat-back exhaust system. This may be lighter and sound ok, but I was concerned the free-flow design may (if it does anything at all) actually lead to less mileage and higher power.

My next thought was simply replacing the muffler with an OEM original cat-back exhaust. This would provide stock power and mileage, and would be nice and quiet.

Going further down this path, I thought about purchasing an OEM style muffler, with a smaller exhaust port than the car came with from the factory. I figure this in addition to a reduced intake port may lead to a leaner burning car, and higher mileage.


I am still really open to ideas at this point, and am hoping someone here may be able to provide some insightful discussion or some personal experiences with exhaust modifications.


Thanks!
Woody

__________________
~ If you don't jump with both feet, you don't move at all ~
2000 Civic DX :: 52/50 psi :: Free Warmer Air Intake :: Duct Tape Aero
"Spare the duct tape, spoil the job."
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 09-27-2013, 04:45 PM   #2 (permalink)
Cyborg ECU
 
California98Civic's Avatar
 
Join Date: Mar 2011
Location: Coastal Southern California
Posts: 6,299

Black and Green - '98 Honda Civic DX Coupe
Team Honda
90 day: 66.42 mpg (US)

Black and Red - '00 Nashbar Custom built eBike
90 day: 3671.43 mpg (US)
Thanks: 2,373
Thanked 2,172 Times in 1,469 Posts
This has been discussed many times... here is a guide to some of those discussions: http://ecomodder.com/forum/showthrea...ead-20689.html
__________________
See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.



  Reply With Quote
Old 09-27-2013, 04:51 PM   #3 (permalink)
The Dirty330 Modder
 
Gealii's Avatar
 
Join Date: Dec 2011
Location: North East Ohio, USA
Posts: 642

CruzeRS - '15 Chevy Cruze LT RS
90 day: 41.29 mpg (US)
Thanks: 10
Thanked 67 Times in 59 Posts
A free flow exhaust can lead to poorer mpg numbers. I am unsure on other vehicles but on ford 302 motors having a single stock exhaust outlet improves upon low end torque which is what hypermilers love. When improved to a high flow true dual exhaust the low end power disappears but the high end improves 4000+ RPM.
__________________



"The only real mistake is the one from which we learn nothing."
- Henry Ford
  Reply With Quote
Old 09-27-2013, 05:17 PM   #4 (permalink)
Master EcoModder
 
cbaber's Avatar
 
Join Date: Feb 2012
Location: Missouri
Posts: 540

Lean and Mean - '98 Honda Civic HX
Team Honda
90 day: 46.69 mpg (US)
Thanks: 30
Thanked 190 Times in 110 Posts
The cat back portion of the exhaust is made of multiple sections, so if your leak is coming from around the muffler, you may only need to replace the axle back section. I bought a cheap ebay axle back section and it has served well over the past couple years. The OEM Honda part is double the price.
__________________
1998 Honda Civic HX - My Project Thread

  Reply With Quote
Old 09-27-2013, 05:36 PM   #5 (permalink)
Hypermiler
 
PaleMelanesian's Avatar
 
Join Date: Dec 2007
Location: Texas
Posts: 2,321

PaleCivic (retired) - '96 Honda Civic DX Sedan
90 day: 69.2 mpg (US)

PaleFit - '09 Honda Fit Sport
Team Honda
Wagons
90 day: 44.06 mpg (US)
Thanks: 611
Thanked 433 Times in 283 Posts
My 96 had that. The pipe coming in to the muffler rusted. I replaced it with a used OEM item. My mileage was good, so I wouldn't mess with it.
__________________



11-mile commute: 100 mpg - - - Tank: 90.2 mpg / 1191 miles
  Reply With Quote
Old 09-27-2013, 05:40 PM   #6 (permalink)
Hypermiler
 
PaleMelanesian's Avatar
 
Join Date: Dec 2007
Location: Texas
Posts: 2,321

PaleCivic (retired) - '96 Honda Civic DX Sedan
90 day: 69.2 mpg (US)

PaleFit - '09 Honda Fit Sport
Team Honda
Wagons
90 day: 44.06 mpg (US)
Thanks: 611
Thanked 433 Times in 283 Posts
Oh, and no exhaust will make it run leaner. The O2 sensors read the actual exhaust and the computer adjusts fuel input to match.
__________________



11-mile commute: 100 mpg - - - Tank: 90.2 mpg / 1191 miles
  Reply With Quote
The Following User Says Thank You to PaleMelanesian For This Useful Post:
Daox (09-28-2013)
Old 09-28-2013, 08:59 AM   #7 (permalink)
Certified Duct Tape Tech.
 
swoody's Avatar
 
Join Date: Feb 2008
Location: Chicago, USA
Posts: 76

Slow Ride - '00 Honda Civic DX
90 day: 46.32 mpg (US)
Thanks: 0
Thanked 0 Times in 0 Posts
Thanks for the quick replies everyone!

That's kind of what I figured - the exhaust wouldn't play a noticable part in the overall mileage nor performance of the car.

I had been looking around just for the axle-back section and think I may splurge for something along these lines:
Walker Exhaust 18561 Exhaust Muffler Muffler | eBay
Bosal 163 727 Exhaust Muffler Rear Silencer | eBay


I can tell that the car is due for a general maintenance though - replacing all fluids, filters, spark plugs, injector cleaning, etc. The car labours just momentarily when starting it cold, or when it has low fuel in the tank. I think some new parts may help out in it running efficiently and maintaining it's longevity.


Thanks again for all the level-headed advice guys

Woody
__________________
~ If you don't jump with both feet, you don't move at all ~
2000 Civic DX :: 52/50 psi :: Free Warmer Air Intake :: Duct Tape Aero
"Spare the duct tape, spoil the job."
  Reply With Quote
Old 09-28-2013, 10:00 AM   #8 (permalink)
Master EcoModder
 
Ryland's Avatar
 
Join Date: Jan 2008
Location: Western Wisconsin
Posts: 3,903

honda cb125 - '74 Honda CB 125 S1
90 day: 79.71 mpg (US)

green wedge - '81 Commuter Vehicles Inc. Commuti-Car

Blue VX - '93 Honda Civic VX
Thanks: 867
Thanked 433 Times in 353 Posts
While a larger exhaust will not directly cause your car to burn more gas, it will shift the power band higher, leading to less power at lower revs unless you drive with a heavier foot.
advantage is that larger, open exhaust will let you hear the engines tone and you'll know sooner when you are pressing to hard on the accelerator pedal.

There are online calculators that will tell you the correct size exhaust you need for a given RPM and engine displacement.

  Reply With Quote
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com