Go Back   EcoModder Forum > EcoModding > Hypermiling / EcoDriver's Ed
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 08-16-2012, 10:14 PM   #1 (permalink)
EcoModding Lurker
 
Join Date: Aug 2010
Location: Washington
Posts: 40
Thanks: 5
Thanked 7 Times in 5 Posts
Newbie Driving Questions about my VX...

So, just started driving the VX today. I have a few questions that maybe you guys would know or be able to help with.

1) When does VTEC engage on a VX? I assume it is different than the run of the mill performance oriented VTEC.

2) Does it try running in lean burn MOST of the time or typically only at freeway speeds? I felt like I was in it a lot., but I am still trying to determine if I am feeling it correctly.

3)Since lean burn allows a lot more air into the system, would my theory be correct that when lean burn engages, you would observe a drop in vacuum? I feel like I saw that. So, while I am typically trying to get higher vacuum for good FE, when I see that sudden drop in Hg, but without me making a change, I assume that is lean burn allowing more air in.

4) HILLS?????? I have a few small mountain passes that I go over in my daily commute. I am still a bit confused as to what the main goal is for best FE. If I don't want to drop below 60mph, should I "floor" it in 5th or give it a little bit of throttle in 3rd. I have much higher vacuum when in 3rd, but in 5th I am at lower rpms... I guess I struggle with the overall balance of rpms and Hg in the hypermilage game...

Any and all comments and advice would be a big help, thanks!

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 08-16-2012, 11:32 PM   #2 (permalink)
Batman Junior
 
MetroMPG's Avatar
 
Join Date: Nov 2007
Location: 1000 Islands, Ontario, Canada
Posts: 21,761

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

MPGiata - '90 Mazda Miata
90 day: 53.56 mpg (US)

Winter beater Metro - '00 Chevrolet Metro
90 day: 61.98 mpg (US)

Fancy Metro - '14 Mitsubishi Mirage top spec
90 day: 58.72 mpg (US)

Even Fancier Metro - '14 Mitsubishi Mirage top spec
90 day: 66.29 mpg (US)
Thanks: 3,473
Thanked 6,281 Times in 3,250 Posts
Get yourself an MPGuino - it'll help your driving SO much. It also works as a lean burn indicator, since your instant MPG will jump up noticeably when you enter L.B.

Quote:
Originally Posted by gijoe985 View Post
2) Does it try running in lean burn MOST of the time or typically only at freeway speeds? I felt like I was in it a lot., but I am still trying to determine if I am feeling it correctly.
It's load based. So it's possible you're feeling it at lower speeds and in gears other than 5th.

Quote:
3)Since lean burn allows a lot more air into the system
In lean burn, air consumption stays about the same for a given power output. It's the fuel input that drops. If your VX is like my Insight, you may have to open the throttle very slightly more to maintain a given speed when you enter lean burn, which would show up on your vacuum gauge.

Quote:
4)Hills .... If I don't want to drop below 60mph, should I "floor" it in 5th or give it a little bit of throttle in 3rd.
An MPGuino will answer this ... and will tell you to stay in the highest gear you can.

Also: MPGuino, MPGuino, MPGuino. (Big fan of instrumentation. It's invaluable.)
__________________
Latest mods: 3-cylinder Mitsubishi Mirage. EcoMods now in progress...
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
Old 08-17-2012, 02:29 PM   #3 (permalink)
Master EcoModder
 
basjoos's Avatar
 
Join Date: Dec 2007
Location: Upstate SC
Posts: 1,059

Aerocivic - '92 Honda Civic CX
Last 3: 70.54 mpg (US)

AerocivicLB - '92 Honda Civic CX
Team Honda
90 day: 55.14 mpg (US)

Camryglide - '20 Toyota Camry hybrid LE
90 day: 57.22 mpg (US)
Thanks: 6
Thanked 590 Times in 277 Posts
1) VTEC engages when rpm goes above 2500.

2) Once the engine reaches normal operating temperature, it runs in lean burn whenever the manifold pressure remains above a preset limit (under low load, mostly closed throttle). Lean burn limits are controlled by manifold pressure Usually you can feel a slight stumble as the engine enters and leaves lean burn.

In my car I get better mileage when flooring it in 5th rather than running partial throttle in 4th.

__________________
aerocivic.com
  Reply With Quote
The Following User Says Thank You to basjoos For This Useful Post:
MetroMPG (08-17-2012)
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com