Do aftermarket headers and exhaust systems really improve fuel economy? - JeepForum.com
Search  
Sign Up   Today's Posts
User: Pass: Remember?
Advertise Here
Jeep Home Jeep Forum Jeep Classifieds Jeep Registry JeepSpace Jeep Reviews Jeep Gallery Jeep Clubs Jeep Groups Jeep Videos Jeep Events Jeep Articles
Go Back JeepForum.com > Models > Jeep Wrangler Forums > TJ Wrangler Technical Forum > Do aftermarket headers and exhaust systems really improve fuel economy?

Introducing MONSTALINER™ UV Permanent DIY Roll On Bed LineBrand New! Quadratec LED Headlights!New Vendor - ARTEC Industries Battery Mounts

Reply
Unread 05-17-2007, 12:05 AM   #1
CB3
Web Wheeler
2006 LJ Wrangler 
 
Join Date: Apr 2007
Posts: 3,851
Do aftermarket headers and exhaust systems really improve fuel economy?

Do aftermarket headers and exhaust systems really improve fuel economy?

I've heard so from a few local guys. They say aftermarket header, exhaust system, and a new chip and the fuel economy goes up. Any truth to that?

CB3 is offline   Reply With Quote
Unread 05-17-2007, 05:18 AM   #2
spyder6
Got that Toyota chit
 
spyder6's Avatar
2010  
 
Join Date: Feb 2006
Location: Louisville, KY
Posts: 12,038
i have an intake and an exhuast and my fuel economy has improved, not by much though, i can tell seat of the pants power aswell.
__________________
2010 Magnetic Toyota 4Runner Trail Teams

My builds: Bruiser and The Grey

|Forge Overland| or follow us on Facebook
spyder6 is offline   Reply With Quote
Unread 05-17-2007, 06:39 AM   #3
joeyt17
Registered User
2001 TJ Wrangler 
 
Join Date: May 2004
Location: Elgin, Illinois
Posts: 217
after parts and labor....it wont pay for itself. even with these high gas prices
__________________
Steel Blue Pearl 2001 TJ
D30/44 on 33" Cooper MT's
about 4" of lift[/CENTER]
joeyt17 is offline   Reply With Quote
Unread 05-17-2007, 07:10 AM   #4
BronYon
Registered User
2001 TJ Wrangler 
 
Join Date: Mar 2007
Location: Little Rock, Arkansas
Posts: 274
You can always do labor yourself to save some cash . I guess those mods are more considered cosmetic though. The intake will offer you noticeable performance by the seat of your pants and will sound cool. The exhaust will also sound cool too. Both might offer you 1 mpg or a little more gain. It's all about where you want your money to go. I'd go for it unless you are aiming to buy a lift or diff mods along those lines, which will offer direct obvious performance gains off road.
__________________
5 Speed White 01 TJ Sport, D30/D44 3.73 gears, 33/12.5/15 BFG All Terrains, Front Aussie locker Rear TruTrac, 4.5" RE Superflex, sye, Coast cv driveshaft, OME shocks, rear adj. track bar, Aem intake with throttle body spacer, FlowMaster 40 muffler with 2.5" pipes, Optima Red Top.

Next upgrades: body mounted sliders, engine skid, repaint door handles. (Then I hope I'm finished for a while!)
BronYon is offline   Reply With Quote
Unread 05-17-2007, 07:44 AM   #5
jeeptj19992001
Registered User
 
Join Date: Oct 2005
Location: Bushkill pa
Posts: 1,078
it will only take about a 100 years to see the payback.......
you drive a shoe box, the only way to get better milage is not to drive it.
__________________
03 rubi....growing bigger and better every day...
jeeptj19992001 is offline   Reply With Quote
Unread 05-17-2007, 10:49 AM   #6
halfmoonclip
Registered User
2004 TJ Wrangler 
 
Join Date: Sep 2003
Location: Westsylvania
Posts: 1,839
In a word, no.
Moon
__________________
'04 Rubi, manual, usual options, Hella H-4s, any range lockers, Randy's booster seats, Oly pushbar, 245/75R16 BFG
'09 Audi A4 Avant- my bride's schnellpuffenpanzer
'12 Ford Focus-the sure way to get good Jeep mileage
'07 Dodge Caliber R/T AWD-da kid's ride
Goodbye Old Blue XJ; 10+yrs, 100K+ miles; virtually trouble free; Long may you run!
halfmoonclip is offline   Reply With Quote
Unread 05-17-2007, 11:35 AM   #7
CB3
Web Wheeler
2006 LJ Wrangler 
 
Join Date: Apr 2007
Posts: 3,851
So it helps hosspower, but not gas mileage?

or not gas mileage enough to be worth it for that?

I don't need more power. I'm good there. I want more mpg though.

I know a few local guys who claim to have gained mpg by better intake, Borla header, cat back exhaust of brand I forgot on one guy's rig, and local custom exhaust on other guy's rig, and a new chip.

Actually, I know 4 local guys who've done that. Two claim to have gained 2 mpg. Another claims to have gained 3 mpg, and one claims to have gained 5 mpg.

Now I know these local guys well. I'd say the guys who claim 2 to 3 mpg are reliable, trustworthy guys I'd likely believe, but I still wanted to hear what you guys think cause I'm always a skeptic about mpg claims. However, even if they are telling the truth, which they probably are, it doesn't make it cost effective cause those mods are expensive (and might interfere with skid plates).

The local guy who claims 5 mpg is full of crap in my opinion because he's a known bull pooper. He fools himself, but he ain't foolin anyone else. I really hate BSers.
CB3 is offline   Reply With Quote
Unread 05-17-2007, 11:45 AM   #8
Jerry Bransford
Do it right or not at all
 
Jerry Bransford's Avatar
2004 TJ Wrangler 
 
Join Date: Jan 2003
Location: Escondido, California, California
Posts: 60,368
The Jeep already has headers. Jeep is under IMMENSE federal pressure to up their CAFE (corporate average fleet economy) mpg averages and if they could further improve on them by a simple exhaust system design change, they'd be all over it.
__________________
Getting Savvy...

Coolest offroad magazine ever! CRAWL Magazine

When you have a choice, buy American.

Jerry Bransford is offline   Reply With Quote
Unread 05-17-2007, 11:46 AM   #9
bairy
Registered User
2006 LJ Wrangler 
 
Join Date: Aug 2006
Location: Murrieta CA
Posts: 1,370
OEMs try very hard to get the most MPG they can. This means, making the engine run more efficiently and reducing mass on the vehicle. Aftermarket headers do both. But who trusts the OEMs and their dyno numbers. I am sure they purposely did not make them as efficient as they could

I am sure the aftermarket headers do flow more and weigh less. But at how much of a difference? The money you spend on those will get you a long long way in gas. If you have money to blow, and you might want a coupe extra HP on the butt dyno, then go for it. Otherwise you will gain much better mpg and hp by never filling your gas tank over 1/4 for weight savings.
__________________
2006 LJ Claytonized
1999 TJ stockish
1987 J20
bairy is offline   Reply With Quote
Unread 05-17-2007, 12:02 PM   #10
jeeptj19992001
Registered User
 
Join Date: Oct 2005
Location: Bushkill pa
Posts: 1,078
Quote:
Originally Posted by CB3
So it helps hosspower, but not gas mileage?

or not gas mileage enough to be worth it for that?

I
Actually, I know 4 local guys who've done that. Two claim to have gained 2 mpg. Another claims to have gained 3 mpg, and one claims to have gained 5 mpg.

Now I know these local guys well. I'd say the guys who claim 2 to 3 mpg are reliable, trustworthy guys I'd likely believe, but I still wanted to hear what you guys think cause I'm always a skeptic about mpg claims. However, even if they are telling the truth, which they probably are, it doesn't make it cost effective cause those mods are expensive (and might interfere with skid plates).

rs.

liar liar pants on fire
__________________
03 rubi....growing bigger and better every day...
jeeptj19992001 is offline   Reply With Quote
Unread 05-17-2007, 01:25 PM   #11
Jeepguy1977
Registered User
1998 TJ Wrangler 
 
Join Date: Feb 2007
Location: Tacoma, Washington
Posts: 2,179
And another little tidbit for thought, DO NOT BOTHER REMOVING THE FACTORY HEADER UNLESS IT IS CRACKED ALREADY!!!! It's way too hard to find an aftermarket header that won't crack. So scratch the header idea. If it cracks, then get a cheapo one off of Ebay or the top left of this forum page.

As for a cat-back, you'd likely give up some torque if it increases the tubing size.
__________________
1998 TJ, 4.0L Auto and various junk
Rolled Red Jeep Club Member #7
Jeepguy1977 is offline   Reply With Quote
Unread 05-17-2007, 02:34 PM   #12
CB3
Web Wheeler
2006 LJ Wrangler 
 
Join Date: Apr 2007
Posts: 3,851
Quote:
Originally Posted by Jerry Bransford
The Jeep already has headers. Jeep is under IMMENSE federal pressure to up their CAFE (corporate average fleet economy) mpg averages and if they could further improve on them by a simple exhaust system design change, they'd be all over it.
Well, they did improve mpg by coming out with the 07 Wrangler version. Correct?

However, that doesn't retroactively help those of us with 06 and older.

I'm not being a smart aleck. It just seems to me that's how it is.
CB3 is offline   Reply With Quote
Unread 05-17-2007, 02:38 PM   #13
CB3
Web Wheeler
2006 LJ Wrangler 
 
Join Date: Apr 2007
Posts: 3,851
Anyhow, you guys are making me feel a lot better about having stock header and exhaust system.

How about at least getting a larger catalytic converter and a flowmaster muffler?

Wouldn't that help some and do it on the relatively cheap?
CB3 is offline   Reply With Quote
Unread 05-17-2007, 02:38 PM   #14
Jerry Bransford
Do it right or not at all
 
Jerry Bransford's Avatar
2004 TJ Wrangler 
 
Join Date: Jan 2003
Location: Escondido, California, California
Posts: 60,368
Quote:
Originally Posted by CB3
Well, they did improve mpg by coming out with the 07 Wrangler version. Correct?
Do you believe that could have been the result of a simple exhaust system modification?
__________________
Getting Savvy...

Coolest offroad magazine ever! CRAWL Magazine

When you have a choice, buy American.

Jerry Bransford is offline   Reply With Quote
Unread 05-17-2007, 02:42 PM   #15
Jerry Bransford
Do it right or not at all
 
Jerry Bransford's Avatar
2004 TJ Wrangler 
 
Join Date: Jan 2003
Location: Escondido, California, California
Posts: 60,368
Quote:
Originally Posted by CB3
How about at least getting a larger catalytic converter and a flowmaster muffler?
Wide open exhausts help increase HP at wide-open throttle and very high RPMs but they don't do anything for fuel economy or around the town/trail performance. Depending on which school of thought you subscribe to, such systems help high-end HP at the expense of low-end torque... which I believe.
__________________
Getting Savvy...

Coolest offroad magazine ever! CRAWL Magazine

When you have a choice, buy American.

Jerry Bransford is offline   Reply With Quote
Reply

Tags
fuel economy
Thread Tools


Suggested Threads





Jeep, Wrangler, Cherokee, Grand Cherokee, and other models are copyrighted and trademarked to Jeep/Chrysler Corporation. JeepForum.com is not in any way associated with Jeep or the Chrysler Corp.