Go Back   EcoModder Forum > EcoModding > General Efficiency Discussion
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 12-30-2013, 06:31 PM   #1 (permalink)
EcoModding Lurker
 
Join Date: Nov 2013
Location: NEPA
Posts: 13
Thanks: 0
Thanked 1 Time in 1 Post
Why no more lean burn??

If the Honda VX and HX were so good at achieving fuel mileage with lean burn, why is it not in all current Hondas and other economy cars?

May seem like a simple question or stupid question, but those are the sought after cars....why not keep using the "lean burn"? What did they find wrong with it?

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 12-30-2013, 06:41 PM   #2 (permalink)
Master EcoModder
 
Join Date: May 2012
Location: USA
Posts: 2,643
Thanks: 1,502
Thanked 279 Times in 229 Posts
Too much nox generation.
  Reply With Quote
The Following 3 Users Say Thank You to Cobb For This Useful Post:
Panther140 (10-17-2017), Shawn D. (03-18-2014), Xist (08-21-2017)
Old 12-30-2013, 06:59 PM   #3 (permalink)
...beats walking...
 
Join Date: Jul 2009
Location: .
Posts: 6,190
Thanks: 179
Thanked 1,525 Times in 1,126 Posts
Q: Why no more lean burn??

A: EPA regulations.

Notice how "Best Economy" (blue line, ie: Lean Burn) coincides with NOx peak in below graph...and, remember, it's NOx which creates LA's brown-smog.



• source: EndTuning - Air Fuel Ratios

Last edited by gone-ot; 12-31-2013 at 12:09 AM..
  Reply With Quote
The Following 8 Users Say Thank You to gone-ot For This Useful Post:
ChazInMT (01-01-2014), Cobb (12-31-2013), COcyclist (11-24-2017), ECONORAM (01-06-2014), mikeyjd (02-20-2014), Shawn D. (03-18-2014), SoobieOut (01-01-2014), Xist (08-21-2017)
Old 12-30-2013, 08:07 PM   #4 (permalink)
It's all about Diesel
 
cRiPpLe_rOoStEr's Avatar
 
Join Date: Oct 2012
Location: Porto Alegre, Rio Grande do Sul, Brazil
Posts: 12,548
Thanks: 0
Thanked 1,622 Times in 1,447 Posts
Big Oil hates lean-burn.
  Reply With Quote
The Following 4 Users Say Thank You to cRiPpLe_rOoStEr For This Useful Post:
Cobb (12-31-2013), EcoCivic (01-09-2018), j12piprius (03-31-2015), mikeyjd (02-20-2014)
Old 12-30-2013, 10:07 PM   #5 (permalink)
Batman Junior
 
MetroMPG's Avatar
 
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 22,513

Blackfly - '98 Geo Metro
Team Metro
Last 3: 70.09 mpg (US)

MPGiata - '90 Mazda Miata
90 day: 52.71 mpg (US)

Even Fancier Metro - '14 Mitsubishi Mirage top spec
90 day: 70.75 mpg (US)

Appliance car - '14 Mitsubishi Mirage ES (base)
90 day: 60.16 mpg (US)
Thanks: 4,058
Thanked 6,957 Times in 3,602 Posts
NOX isn't the problem

NOx emissions were actually NOT a problem for the gen. 1 Insight. 2 catalytic converters, one specifically designed to store/process NOX meant the lean-burn car was rated ULEV (Ultra-Low Emissions Vehicle) by CARB, with 50% lower emissions than an average new car (ie. non-lean burn). Independent dyno testing supposedly found no NOx in the Insight's exhaust. (Source)

(This *was* a problem for the older, lean-burn Civic VX, which didn't have a NOx catalyst, so wasn't sold in Cali.)

So if it's not NOx itself, maybe the additional cost of emissions control to deal with the issue is one reason. The NOx cat was a ~$1200 (retail) part.

Another major reason it may be gone could be driveability issues/consumer acceptance. In my Insight, there was a noticeable change in engine character when lean burn engaged: throttle response deadened, power output as a function of throttle position changed noticeably.

My car also had a very slight (but noticeable if you're attuned to the car) "stumble" when transitioning into lean burn. And then again when going in & out of periodic NOx purge events (about every minute or 2 cruising at 80 km/h / 50 mph).

The Insight's EGR system (which also helped regulate NOx, and was possibly active much more than on non-lean burn cars) tended to gum up over time, causing even more driveability issues.

I could see these things bothering lots of drivers.

Also, it required an a lot of care/attention to take advantage of lean burn to truly maximize its benefit, something most drivers wouldn't bother with. (IE. finessing the throttle to hold lean burn as much as possible as power demands change.)

The cost/benefit balance for the average driver probably doesn't work out.
__________________
Project MPGiata! Mods for getting 50+ MPG from a 1990 Miata
Honda mods: Ecomodding my $800 Honda Fit 5-speed beater
Mitsu mods: 70 MPG in my ecomodded, dirt cheap, 3-cylinder Mirage.
Ecodriving test: Manual vs. automatic transmission MPG showdown



EcoModder
has launched a forum for the efficient new Mitsubishi Mirage
www.MetroMPG.com - fuel efficiency info for Geo Metro owners
www.ForkenSwift.com - electric car conversion on a beer budget
  Reply With Quote
The Following 13 Users Say Thank You to MetroMPG For This Useful Post:
blownb310 (03-18-2014), Bugzilla (01-02-2014), Cd (12-31-2013), christofoo (01-04-2014), ECONORAM (01-06-2014), mikeyjd (02-20-2014), NachtRitter (12-31-2013), niky (12-31-2013), pgfpro (12-30-2013), RustyLugNut (12-31-2013), slownugly (12-31-2013), UltArc (12-30-2013), Xist (08-21-2017)
Old 12-31-2013, 09:15 AM   #6 (permalink)
Burn lean and prosper\\//
 
Join Date: Jul 2012
Location: scranton pa
Posts: 576

VLX - '93 Honda Civic VLX
Team Honda
90 day: 51.1 mpg (US)
Thanks: 55
Thanked 65 Times in 54 Posts
Perfect Darin.

One thing I was thinking about is what if car buyers were better educated about lean burn operation when purchasing these cars new. I was just a wee lad when the vx and hx were in the showroom so I'm not sure how knowledgable the salesmen were about the cars and if they used that knowledge to educate the buyers and potential buyers.

Heck some "Honda enthusiasts" put these vxs for sale and they don't even know what they are about. Some ads feature the stock vx drivetrain with aftermarket intake/ header. Then the seller says "this car is fast vtec kicks in hard" When in fact the car is slow as balls and they are used to driving an 86 escort.
__________________
Burn lean and prosper \\ //
  Reply With Quote
Old 12-31-2013, 03:38 PM   #7 (permalink)
Master EcoModder
 
Join Date: Nov 2012
Location: San Diego, California
Posts: 982
Thanks: 271
Thanked 385 Times in 259 Posts
There will be new developments to be sure.

Lean Burning engines is under much scrutiny. Along with improved controls, there will be applications with larger drive cycle regimes and much more seamless transitions. Of course, if a driver still insists on heavy footed driving, no technology is going to help them.
  Reply With Quote
Old 12-31-2013, 04:19 PM   #8 (permalink)
...beats walking...
 
Join Date: Jul 2009
Location: .
Posts: 6,190
Thanks: 179
Thanked 1,525 Times in 1,126 Posts
Quote:
Originally Posted by RustyLugNut View Post
Lean Burning engines is under much scrutiny. Along with improved controls, there will be applications with larger drive cycle regimes and much more seamless transitions. Of course, if a driver still insists on heavy footed driving, no technology is going to help them.
Yep, no amount of 'technology' can "...idiot-proof idiots..."
  Reply With Quote
Old 12-31-2013, 05:02 PM   #9 (permalink)
Not Doug
 
Xist's Avatar
 
Join Date: Jun 2012
Location: Show Low, AZ
Posts: 12,185

Chorizo - '00 Honda Civic HX, baby! :D
90 day: 35.35 mpg (US)

Mid-Life Crisis Fighter - '99 Honda Accord LX
90 day: 34.2 mpg (US)

Gramps - '04 Toyota Camry LE
90 day: 35.39 mpg (US)

Don't hit me bro - '05 Toyota Camry LE
90 day: 35.79 mpg (US)
Thanks: 7,216
Thanked 2,217 Times in 1,708 Posts
Idiocy will find a way!
  Reply With Quote
The Following User Says Thank You to Xist For This Useful Post:
MetroMPG (12-31-2013)
Old 12-31-2013, 05:54 PM   #10 (permalink)
In Lean Burn Mode
 
pgfpro's Avatar
 
Join Date: Apr 2009
Location: Pacific NW
Posts: 1,528

MisFit Talon - '91 Eagle Talon TSi
Team Turbocharged!
90 day: 39.03 mpg (US)

Warlock - '71 Chevy Camaro

Fe Eclipse - '97 Mitsubishi Eclipse GS
Thanks: 1,243
Thanked 580 Times in 372 Posts
In the future I think we will see Stratified 'Ultra Lean Burn Engines" at 65:1 A/F ratios running "Gasoline Direct Injection" and "Spray Guided Piston Injection" in conjunction with new Turbo Charger technology in the forms of "Turbo Compounding Motor Generation Units Heat" and dual stage high-pressure/low pressure turbos systems.

__________________
Pressure Gradient Force
The Positive Side of the Number Line

  Reply With Quote
The Following 3 Users Say Thank You to pgfpro For This Useful Post:
BabyDiesel (04-29-2015), Cobb (12-31-2013), dirtydave (01-10-2015)
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