PerformanceTrucks.net Forums

Tuning, Diagnostics, Electronics, and Wiring HP Tuners | EFILive | Hand Held Programmers | Stand Alone PCM's | Electronics | Wiring Diagrams

Tuning for Gas mileage

Thread Tools
 
Search this Thread
 
Old Mar 7, 2007 | 09:55 PM
  #11  
dc_justin's Avatar
dc_justin
Hello Dave
iTrader: (13)
 
Joined: Jul 2004
Posts: 1,119
Likes: 3
From: San Diego, CA
Default
Originally Posted by dirt_track_racer_81
go speed denisty and lean it out to 15.6 at cruise..thats what ive done to my truck..did it to dozerdans old truck also..he went from around 17 stock and put the cam and speed denisty tune in and he got around 22
Just to be clear, it's not necessary to go speed density in order to use EFILive's commanded fuel x rpm x map table. It will still function exactly the same way with the MAF enabled.

Originally Posted by DozerDan
i prolly have no idea what i'm talking about but, i'd max timing and run 91 or whatever...don't the computers pull timing when a lower octane is detected to "prevent" detonation? pulled timing means less performance/mileage right?
There is no "octane sensor" or anything of that type. The PCM will attempt to run the high octane table, and based on the activitiy of the knock sensors, it will use some blend of the high and low octane tables. This may be what you were saying, just wanted to be clear.
Reply
0
Old Mar 7, 2007 | 10:28 PM
  #12  
onebadrubi's Avatar
onebadrubi
Thread Starter
TECH Fanatic
 
Joined: Dec 2005
Posts: 1,932
Likes: 0
From: arkansas
Default
DC justin what would you recommend to get optimal gas mileage?
Reply
0
Old Mar 7, 2007 | 10:34 PM
  #13  
alanderson1978's Avatar
alanderson1978
TECH Apprentice
iTrader: (1)
 
Joined: Nov 2006
Posts: 334
Likes: 0
From: Blytheville, AR
Default
Changing the VE, or commanded fuel x rpm x map(?) in EFILive, won't do you any good in MAF OR SD mode if you're in closed loop. Fuel trims will just compensate to keep ya at 14.7 AFR. You will need to be in open loop to really make a difference. There may be a few other ways, but I don't like talking about MPG in public forums. Just wanted to make a point that there is a difference between MAF/SD and OL/CL.
Reply
0
Old Mar 7, 2007 | 10:37 PM
  #14  
onebadrubi's Avatar
onebadrubi
Thread Starter
TECH Fanatic
 
Joined: Dec 2005
Posts: 1,932
Likes: 0
From: arkansas
Default
Why do you say you dont like talking about MPG in public forums?
Reply
0
Old Mar 7, 2007 | 10:48 PM
  #15  
dc_justin's Avatar
dc_justin
Hello Dave
iTrader: (13)
 
Joined: Jul 2004
Posts: 1,119
Likes: 3
From: San Diego, CA
Default
Originally Posted by alanderson1978
Changing the VE, or commanded fuel x rpm x map(?) in EFILive, won't do you any good in MAF OR SD mode if you're in closed loop. Fuel trims will just compensate to keep ya at 14.7 AFR. You will need to be in open loop to really make a difference. There may be a few other ways, but I don't like talking about MPG in public forums. Just wanted to make a point that there is a difference between MAF/SD and OL/CL.
Correct. I was referring to his implied usage of the semi-closed loop feature of COS3/5.

Originally Posted by onebadrubi
Why do you say you dont like talking about MPG in public forums?
Some methods would be questionable by certain authorities...
Reply
0
Old Mar 7, 2007 | 10:53 PM
  #16  
dc_justin's Avatar
dc_justin
Hello Dave
iTrader: (13)
 
Joined: Jul 2004
Posts: 1,119
Likes: 3
From: San Diego, CA
Default
Originally Posted by onebadrubi
DC justin what would you recommend to get optimal gas mileage?
Really, with a tune that runs in closed loop (while switching at 450mv), your best bet is to have timing at it's optimal level (the point where best torque is made). And to find this, you need a dyno.

Other gains can be made by adjusting the torque converter apply settings as well as potentially adjusting your part throttle shift points.
Reply
0
Old Mar 7, 2007 | 11:00 PM
  #17  
alanderson1978's Avatar
alanderson1978
TECH Apprentice
iTrader: (1)
 
Joined: Nov 2006
Posts: 334
Likes: 0
From: Blytheville, AR
Default
Originally Posted by dc_justin
Correct. I was referring to his implied usage of the semi-closed loop feature of COS3/5.
I use HP Tuners, so I don't know what the EFILive numbers mean.

Originally Posted by dc_justin
Some methods would be questionable by certain authorities...
Reply
0
Old Mar 7, 2007 | 11:07 PM
  #18  
dc_justin's Avatar
dc_justin
Hello Dave
iTrader: (13)
 
Joined: Jul 2004
Posts: 1,119
Likes: 3
From: San Diego, CA
Default
Originally Posted by alanderson1978
I use HP Tuners, so I don't know what the EFILive numbers mean.
Ah. Well, in that case, I'll fill you in a bit. What is referred to in the HPT realm as the OLFA table has been re-configured with EFILive to act as a more versatile commanded fuel table (in similar format to the VE table). With closed loop disabled, any point in the new OLFA table that is commanded at 14.7:1 will drop into closed loop, and any other point remains in open. Allows for some creative fueling techniques.
Reply
0
Old Mar 7, 2007 | 11:20 PM
  #19  
onebadrubi's Avatar
onebadrubi
Thread Starter
TECH Fanatic
 
Joined: Dec 2005
Posts: 1,932
Likes: 0
From: arkansas
Default
Gotcha on the authorities thing.
Reply
0
Old Mar 9, 2007 | 04:06 PM
  #20  
SS_bnoon_SS's Avatar
SS_bnoon_SS
TECH Enthusiast
iTrader: (3)
 
Joined: Nov 2005
Posts: 655
Likes: 0
From: West Des Moines, Iowa
Default
Originally Posted by dc_justin
Ah. Well, in that case, I'll fill you in a bit. What is referred to in the HPT realm as the OLFA table has been re-configured with EFILive to act as a more versatile commanded fuel table (in similar format to the VE table). With closed loop disabled, any point in the new OLFA table that is commanded at 14.7:1 will drop into closed loop, and any other point remains in open. Allows for some creative fueling techniques.

So in HPT then you would need to drop the MAF and go SD then to accomplish the same thing via commanded fuel, right?
Reply
0



Advanced Search

All times are GMT -5. The time now is 07:14 PM.