Hi Guys,
Reading through previous posts about fuel economy i couldnt find to much about piggy-back ECU's. Has anyone had much luck saving fuel with them and what units have people had the most luck with. like everyone else i am chasing a little more economy with current fuel prices as they are. i have a TL which my partner drives around town at about 13.5 -15.0 ltrs/100 kms. im sure the engine mapping is rich from the factory as it is their safety margin. any access to the ECU would be good. Any help would be appreciated.

Actually, I think you'll find stock fuel settings rather conservative, but there's no economical way to shift 1500kg of car around town unless you're running it on gas.

Piggyback ECUs will likely make your car drink more, not less!

Hi Guys,
Reading through previous posts about fuel economy i couldnt find to much about piggy-back ECU's. Has anyone had much luck saving fuel with them and what units have people had the most luck with. like everyone else i am chasing a little more economy with current fuel prices as they are. i have a TL which my partner drives around town at about 13.5 -15.0 ltrs/100 kms. im sure the engine mapping is rich from the factory as it is their safety margin. any access to the ECU would be good. Any help would be appreciated.

Your'e right they do run rich from factory. That's pretty standard. I am running a Greddy Emanage in my car. I got it to get the most out of my mods. I average 10.5-11/100km. Piggy backs are not usually used as an option soley for better fuel economy. Other popular ones proven to work with 3rd gens are Haltech and unichip. expect to up to $1500 for supply, install and tune which requires dyno time to get right.

I think it was 'EGO' who got the a haltech installed and noticed some improvements in fuel economy.

They are tuned relatively aggressively from the factory meaning a piggy back on a stock car might yield only a small power increased.

However the economy should increase as the magna map would be a one size fits all, meaning it has to handle the heat of Alice Springs along with other more sane temperatures. 90% of stock cars run rich to avoid detonation, so theres generally always some room for improvement.

The $1300 - 1700 it will cost could buy a lot of fuel. Try a better flowing muffler and a K&N filter. After a muffler change I got perhaps 10% better economy. Also with a K&N pod it decreased another 1L/100km (mainly due to it running leaner I'm guessing).

why spend $1500 on a piggyback if you dont want extra power, it will still cost you $70+ to fill up. put it on gas, with the rebates around at the moment, didnt it cost someone recently about $100 to put their car on gas?

EDIT: http://www.aussiemagna.com/forums/showthread.php?t=46486


Phew got my TL back from my gas fitter mate.....

.....the conversion cost me $0...!!!

It also depends how you drive the car. If you spent 90% of your time in closed-loop cruise then you won't gain anything from remapping your fuel delivery (a piggy-back can't modify closed-loop).

Most people who have had piggy-back ECUs installed found their car was runing 10.5:1 or richer at WOT which is way too rich for an N/A car and you can pull a fair bit of fuel out there, but you'll only benefit from those changes if you run around under heavy load all the time.

There isn't much margin for error in the ignition timing map, but you can get a little bit more efficiency out of the engine by fine tuning that aspect, which will also give you some small economy benefits.. but again, only under open-loop operation.

why spend $1500 on a piggyback if you dont want extra power, it will still cost you $70+ to fill up. put it on gas, with the rebates around at the moment, didnt it cost someone recently about $100 to put their car on gas?

EDIT: http://www.aussiemagna.com/forums/showthread.php?t=46486

That was my point. if you want extra power you will still get it with a piggyback, around 5hp atw if you have little or no mods if your'e lucky. Keep in mind if it is only for fuel economy, you cant go past the suggestions of gas.

if you could get your hands on a wideband o2 sensor you could see how rich you are running and how much you will gain. if the figure is around 10.5:1 then you will pick up a noticable amount of power leaning it out. i know guys with skylines that have used apexi SAFC2s and picked up about 20% (went from 168kw to 198kw), but that is on a turbo car. an apexi safc2 or afc will set you back about $400 plus tuning.

Just gas it and be done with it! :rant:

Thanks for all the info guys. Always good to get an opinion from someone that has gone through it before.