diesel exhaust - Page 2 - Fuelly Forums

Android Users - Coming Soon! - Migrating from aCar 4.8 to 5.0

Reply
 
Thread Tools Display Modes
 
Old 09-27-2007, 10:51 PM   #11
Registered Member
 
theclencher's Avatar
 
Join Date: Aug 2006
Posts: 542
Country: United States
I should have given thomas some more background the first time...

Anyhow, I'm confused by this: "i was wondering if i got straight open exhaust on it if it should get better mileage... i've heard that diesels don't require any back pressure from the exhaust to run right but i had exhaust on it a while back and it seemed to get 10 mpg anywhere!?!" If you "had exhaust" on it before and got 10, but are getting 14-16 now- presumably with exhaust ("the truck doesnt have a turbo or a cat all it has are the mufflers") what's different?

I am suspicious of Red's (or his friend's) claim of a four inch system yielding a 20-40% mpg increase. It flies in the face of everything I *think I* know about exhausts. Plus, if it was true, you can bet it would have come from the factory that way.

On a different note, it seems to me if you are getting better mpg in the city than on the highway, you are likely burning up too much fuel by pushing massive amounts of air aside with that big square sled. Also, high speed is the enemy of that old-skool tranny w/o lockup converter and OD. Slowing down, being steady or using cc, and airing up those nice high psi, highway tread tires should help.

There are many vehicle mods and driver techniques that remain consistant whether you are driving a ZX2 or an Excursion. Instead of repeating them all again I would urge you to do a search here for all the wonderful knowledge that's already posted.
__________________

__________________
Tempo/Topaz:
Old EPA 23/33/27
New EPA 21/30/24

F150:
New EPA12/14/17

theclencher is offline   Reply With Quote
Old 09-28-2007, 10:55 AM   #12
Registered Member
 
GasSavers_Red's Avatar
 
Join Date: Nov 2006
Posts: 513
Country: United States
Send a message via MSN to GasSavers_Red
Quote:
Originally Posted by theclencher View Post
I am suspicious of Red's (or his friend's) claim of a four inch system yielding a 20-40% mpg increase. It flies in the face of everything I *think I* know about exhausts. Plus, if it was true, you can bet it would have come from the factory that way.
The guy does drive like an @$$ and the thing is lifted, sitting on 38" boggers so it might be off some....
__________________

__________________
GasSavers_Red is offline   Reply With Quote
Old 09-28-2007, 11:56 AM   #13
Registered Member
 
omgwtfbyobbq's Avatar
 
Join Date: Jul 2006
Posts: 1,516
Country: United States
Yeah... Given that a driver can double or half the EPA rating, I would guess that it's kinda hard to attribute any mileage change at all to the exhaust.
__________________
Quote:
Originally Posted by FormulaTwo
I think if i could get that type of FE i would have no problem driving a dildo shaped car.
omgwtfbyobbq is offline   Reply With Quote
Old 01-14-2010, 05:39 AM   #14
Registered Member
 
Join Date: Dec 2009
Posts: 32
Quote:
Originally Posted by skewbe View Post
LOL, those loud a$$ harleys suck major a$$ too.

And it is especially dumb because the bozos riding them probably think they are "all american".


There are tons of faster/quieter/lighter/far less expensive/better looking/reliable bikes out there (thanks Mr Suzuki!).
The American carbs that Harley tried to use for years were unreliable. Those same Japanese carbs are on our ATV's, Jet Ski's, & even lawn mowers. The only thing better is FI.

Dave
__________________
94 vx
93 del Sol
93 Miata
92 Prelude Si
Dave's Civic Duty is offline   Reply With Quote
Old 01-14-2010, 04:31 PM   #15
Senior Member
 
Join Date: Mar 2011
Posts: 446
Country: United States
Location: Charlotte nc
6.2 is an N/A diesel so bigger exhaust probably won't help too much. if you could get your hands on a turbo kit for that it would greatly improve the milage and power.

this article may help even though it is performance oriented the concepts work for milage too.

http://www.dieselpowermag.com/tech/c...dup/index.html
Philip1 is offline   Reply With Quote
Old 01-14-2010, 04:49 PM   #16
Registered Member
 
theholycow's Avatar
 
Join Date: Apr 2008
Posts: 6,624
Country: United States
Send a message via ICQ to theholycow Send a message via AIM to theholycow Send a message via MSN to theholycow Send a message via Yahoo to theholycow
I don't think adding a turbo will increase FE at all. Changing to a smaller engine with a turbo probably would.
__________________
This sig may return, some day.
theholycow is offline   Reply With Quote
Old 01-14-2010, 06:13 PM   #17
Senior Member
 
Join Date: Mar 2011
Posts: 446
Country: United States
Location: Charlotte nc
without adding fuel it will add a little power but make the engine more efficent
Philip1 is offline   Reply With Quote
Old 01-14-2010, 06:24 PM   #18
Registered Member
 
theholycow's Avatar
 
Join Date: Apr 2008
Posts: 6,624
Country: United States
Send a message via ICQ to theholycow Send a message via AIM to theholycow Send a message via MSN to theholycow Send a message via Yahoo to theholycow
I don't see how. A turbo uses exhaust pressure (which comes from pistons) to cram in more air; the fuel injectors add more fuel to match, don't they? Or does it just run leaner because diesels run widely varying ratios? If it just runs leaner, then you're using the pistons to push exhaust to turn a turbine to push more air into the cylinders...sounds like a recipe for loss unless it was running too rich beforehand.
__________________
This sig may return, some day.
theholycow is offline   Reply With Quote
Old 01-14-2010, 06:56 PM   #19
Senior Member
 
Join Date: Mar 2011
Posts: 446
Country: United States
Location: Charlotte nc
the 6.2 runs pig rich when pulling any load. A turbo would lean that out and make use of the fuel rather than wasting it as black smoke. the main reason a turbo would help milage is the 6.2 n/a has 145hp but with a turbo it makes 60 hp more. This will move the 6000+LB Suburban much better than the N/A could ever do. The banks power pack claims 10% increase in milage with an increase of 60hp and 115 lb/ft.
Philip1 is offline   Reply With Quote
Old 01-31-2010, 05:04 PM   #20
Registered Member
 
Join Date: Sep 2007
Posts: 54
Country: United States
I just ordered a 3" downpipe for my powerstroke to go with the 4" exhause it had on it when I bought it. Will post the results when I get it installed
__________________

__________________
http://www.bestamericanoil.com
smay665949 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Server Time ynpmoose Fuelly Web Support and Community News 2 12-20-2013 12:53 PM
All Licensed Drivers terrapin Fuelly Web Support and Community News 0 08-07-2008 10:49 AM
Scan Gauge 2 How it works popimp General Fuel Topics 15 06-20-2007 06:46 PM
Quick release windshield wiper ideas? MetroMPG Aerodynamics 30 12-10-2006 07:02 AM
PepsiCo Connections? SVOboy General Discussion (Off-Topic) 3 10-12-2006 05:52 PM

Powered by vBadvanced CMPS v3.2.3


All times are GMT -8. The time now is 12:25 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.