Page 1 of 1

How to tune for increased MPG?

Posted: 2021 May 28, 15:06
by redtopracer
Anything at all, would be appreciated.


4.10 gears 27 in tires and a t45 have me turning 3100 cruising on the interstate.


So any crumbs I can gather to increase the MPG are going to help.

Re: How to tune for increased MPG?

Posted: 2021 May 28, 16:17
by decipha
2.73 gears and a turbo

Re: How to tune for increased MPG?

Posted: 2021 May 28, 17:08
by redtopracer
im not arguing with you.


cause your not wrong.


But what could be done software wise on my side to improve it?

Re: How to tune for increased MPG?

Posted: 2021 May 29, 02:11
by wwhite
just printed this the other day, taken from 'down under':
I haven't tried myself, but will be thinking about adding a second tune one day.

Tuning for Fuel Economy
When aiming maximum for fuel economy for your car, there are a few tables that can be tweaked via our J3 Chips to help
get a few extra kms from a tank. Here we explain some of those tables and how to weak them for the best results.
  • Volumetric Efficiency (VE) – This table is the major control for fuel. Obviously, you want to dial in your WOT
    mixtures to be safe and produce as much power as possible, but in the cruise area you want to aim for economy.
    Small tweaks in the midrange VE areas to ensure you stay around 14.7 – 15.0 :1 AFR at cruise will set a good
    foundation for economy.
  • MFA Fuel Multiplier – This table is a multiplier that allows the ECU to target higher than stoich AFRs when under
    cruise conditions. It will periodically bring the AFR back down to stoich to keep everything cool. The table in the
    screenshot below is a good start, and your ability to target higher values will depend on your base VE map, as
    well as compression ratio and spark values.
  • Spark table MBT MPG – This table is used during cruise mode to achieve better economy. Use this table to
    target higher advance when cruising. Your base Spark table MBT will also play a big role in part throttle torque
    and economy when in regular mode.
  • Torque Convertor Lockup – These tables can be used to lock up the convertor at lower RPMs, helping achieve
    greater economy.

Re: How to tune for increased MPG?

Posted: 2021 May 29, 03:18
by redtopracer
See I knew that tuning for lean cruise would give me decent bump. And I knew ford was able to do it in the rest of the world, because of the measured metrics for smog being different.



Fucking feds.



Only issue is I'm fairly certain these functions aren't readily available to me.



At least the MFA table. Or I at a minimum don't know what function it's referencing.

Re: How to tune for increased MPG?

Posted: 2021 May 29, 09:01
by decipha
yeah none of that applies

best mpg is achieved when its dialed in properly.

Re: How to tune for increased MPG?

Posted: 2021 May 30, 03:36
by redtopracer
Your killing me duder.


I'm trying to wrinkle out that last 3% of commanded off. And the dang thing gets the same mpg as the stock tune and equipment did.


But I was getting low 20's on the interstate previously running the craj0 setup with 3.08's



I'm getting low 18's now with 4.10's


Guess high KnOx lean cruise is a pipe dream on the stock PCM.

Re: How to tune for increased MPG?

Posted: 2021 May 30, 03:45
by redtopracer
Also, VE table for a MAF equiped car.....




Is it used as a fall back for the inferred MAF function or does it have other purposes here?

Re: How to tune for increased MPG?

Posted: 2021 May 30, 10:37
by decipha
there is no ve table on maf

you can toss her in open loop at cruise and command lean if u desire