ECUs and Tuning Discuss Engine Management, Tuning, & Programming

VVT @cruise for MPG

Thread Tools
 
Search this Thread
 
Old 10-02-2013, 04:23 PM
  #1  
Elite Member
Thread Starter
 
JasonC SBB's Avatar
 
Join Date: Jul 2005
Posts: 6,420
Total Cats: 84
Default VVT @cruise for MPG

Has anyone figured out if you want minimum or maximum overlap?
JasonC SBB is offline  
Old 10-02-2013, 05:07 PM
  #2  
VladiTuned
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 35,821
Total Cats: 3,481
Default

Relevant to my interests.

Hopefully someone has some good info for us. I plan to experiment with it later, but for now its minimal advance in cruise cells for the next few tanks. Tuned on the lean side and hoping to achieve decent mileage on e85.

Last edited by 18psi; 10-03-2013 at 09:23 AM.
18psi is offline  
Old 10-02-2013, 05:14 PM
  #3  
Junior Member
iTrader: (6)
 
300zxrb26dett's Avatar
 
Join Date: Feb 2012
Location: Phoenix, AZ
Posts: 148
Total Cats: 8
Default

I might have some relevant info from a toyota engine I can post when I get home. The pdf is on my home computer.
300zxrb26dett is offline  
Old 10-02-2013, 06:35 PM
  #4  
Junior Member
iTrader: (6)
 
300zxrb26dett's Avatar
 
Join Date: Feb 2012
Location: Phoenix, AZ
Posts: 148
Total Cats: 8
Default

Since I cant seem to upload the file here is the link:
http://rav4world.com/pdf/2009/2009_R...w_Features.pdf
Pg 73 should have the relevant information.
300zxrb26dett is offline  
Old 10-03-2013, 07:04 PM
  #5  
Elite Member
Thread Starter
 
JasonC SBB's Avatar
 
Join Date: Jul 2005
Posts: 6,420
Total Cats: 84
Default

That suggests big overlap to get EGR effects.
JasonC SBB is offline  
Old 10-03-2013, 07:36 PM
  #6  
Junior Member
iTrader: (6)
 
300zxrb26dett's Avatar
 
Join Date: Feb 2012
Location: Phoenix, AZ
Posts: 148
Total Cats: 8
Default

Increasing overlap to
increase internal EGR
to reduce pumping loss

 Better fuel economy
 Improved emission control
These 2 things go hand in hand though. Another thing I would suggest is go digging through the Ecomodder forum and see if you can find more information about cam timing in relation to improving MPG.
300zxrb26dett is offline  
Old 10-08-2013, 02:56 PM
  #7  
Elite Member
iTrader: (24)
 
Bryce's Avatar
 
Join Date: Jul 2007
Location: Cypress, TX
Posts: 3,759
Total Cats: 35
Default

I havent passed the sniffer test here with my 04 motor due to high NOx. I need to get the car back on the road within a few days. This would be much easier than plumbing and controlling a stock egr valve.
Bryce is offline  
Old 10-08-2013, 03:59 PM
  #8  
Elite Member
Thread Starter
 
JasonC SBB's Avatar
 
Join Date: Jul 2005
Posts: 6,420
Total Cats: 84
Default

Excessive overlap can increase HC too because of fuel going straight out the exhaust.
JasonC SBB is offline  
Old 10-08-2013, 05:59 PM
  #9  
Tour de Franzia
iTrader: (6)
 
hustler's Avatar
 
Join Date: Jun 2006
Location: Republic of Dallas
Posts: 29,085
Total Cats: 375
Default

Originally Posted by JasonC SBB
Excessive overlap can increase HC too because of fuel going straight out the exhaust.
When does overlap occur on a stock VVT engine?
hustler is offline  
Old 10-10-2013, 03:52 PM
  #10  
Elite Member
Thread Starter
 
JasonC SBB's Avatar
 
Join Date: Jul 2005
Posts: 6,420
Total Cats: 84
Default

You mean in the stock mapping? Midrange RPMs, dunno how it changes with throttle position / load though.
JasonC SBB is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
StratoBlue1109
Miata parts for sale/trade
21
09-30-2018 01:09 PM
Rick02R
WTB
3
01-03-2016 07:18 PM
russian
Miata parts for sale/trade
6
10-08-2015 03:01 PM
The Gleas
MEGAsquirt
3
10-01-2015 09:30 AM
Greasyman
General Miata Chat
2
09-28-2015 10:44 AM



Quick Reply: VVT @cruise for MPG



All times are GMT -4. The time now is 10:20 AM.