AU best fuel economy tune?

**Stav** · 12-07-2008, 11:10 AM

Fuel is getting expensive..I am paying $1200 in fuel a month. Currently getting 380 kays on a 68litre tank city driving. My goal is to tune the wagon to be as fuel efficient as possible. What are you guys getting out of a tank?

Has anyone tried to do a super fuel economy tune? If so how far can your car go on a tank?

How far can I get by supertuning the wagon for this goal?

MADED-6 · 12-07-2008, 11:38 AM

dam man 380k how do u drive the car and where as in highway around town or what.
i do like 400km a week and use just under 3/4 of a tank thats with melbourne traffic aswell.
but yeah have u got a afr gauge or had the afr's checked?
does it smell like it runs rich/ blow any black smoke?
cheers josh.

StealthAu · 12-07-2008, 12:23 PM

I just filled up yesterday, worked out my economy on the last tank to be 16L/100km but that included 14 WOT dyno runs and a bit of flat footed driving, will be interested to see what it works out to be on this tank.

JMO · 12-07-2008, 12:24 PM

EDIT: Wrong thread

Black XR · 12-07-2008, 02:59 PM

380-400k's towing trailer around town
550-575k's hwy driving no trailer thats from 82ltr tank

**Stav** · 12-07-2008, 04:54 PM

What should the wagon be getting?

Sydney traffic...today I drove from Parramatta to Hyde Park.To drive there and back home took 1 hour and 50 minutes.I spent about 1/1/2 hours in bumper to bumper or red lights.

During the week I carry my big toolbox and fight heavy traffic as well. Wot air fuel ratios have made the car go fantastic.Medium throttle is running rich (11's) according to my air fuel ratio metre.

I am going to log my total air fuel ratios and go from there. What do you guys think I can get it to? 400 kays? 450? 500? What is realistic?

I want to see how good fuel economy I can get from this car.Can I get even 1000 kays on a tank city driving??

**Stav** · 12-07-2008, 05:04 PM

I am thinking of water injection and leaning out the mixtures.Top end tune won't need to be changed. Power will still be there.

T3man · 12-07-2008, 05:09 PM

Up the wrong path there Stav - do not lean out the mixtures with water injection.

I know you've done some mods - can you run your engine and driveline configuration past me please to refresh my memory?

Are you running a Haltech?

5.0 ED · 12-07-2008, 05:10 PM

you could always try doing a hydrogen hybrid.

ratter · 12-07-2008, 05:14 PM

At all throttle settings except heavy acceleration your car should be running in closed loop and it would be acheiving 14.7:1 or stoich.

11:1 is way too fat for medium acceleration and in fact too, fat for WOT

**Stav** · 12-07-2008, 05:15 PM

I have 4:11 gears . Haltech is very tunable to take some more fuel out. I want to take this to a safe lean mxture for daily driving and my logic for water injection is to keep the engine cool for even leaner mixtures.I dont want to burn the valves etc.

waggaclint · 12-07-2008, 05:17 PM

i get constantly 550km every tank out of my wagon..

thats a bit on freeway and a bit the suburbs driving to work every day and around a bit on weekends.....
If i go out of time ill get around 600 odd best ive every gotten was 720km out of tank.....

**Stav** · 12-07-2008, 05:18 PM

Quote:

Originally Posted by ratter

At all throttle settings except heavy acceleration your car should be running in closed loop and it would be acheiving 14.7:1 or stoich.

11:1 is way too fat for medium acceleration and in fact too, fat for WOT

Wot is fine.It falls into 12 to 12.9. My maps need work at 30% throttle to 70%.It is in these cells that I am seeing 11 ..too rich.:(n But not for long. I am going to aim closer to 13 - 12 af here too for a start.Its got to help.

T3man · 12-07-2008, 05:18 PM

Heheheh Stav, I just read your other thread about going the supercharger route. Better decide first up what you want mate - power or economy. Because what you were talking about doing to your car with supercharger is NOT going to give you the economy you are looking for. You can't have the best of both - but you can get a good compromise if you build the engine right.

And, if it's a fuel cost/km issue you have, then the aswer is very simple - dedicated LPG. It will work well with supercharger or turbocharger installations and cut your fuel bill by 30% to 40% over what you are getting now and you will still have power to burn.

**Stav** · 12-07-2008, 05:19 PM

Quote:

Originally Posted by waggaclint

i get constantly 550km every tank out of my wagon..

thats a bit on freeway and a bit the suburbs driving to work every day and around a bit on weekends.....
If i go out of time ill get around 600 odd best ive every gotten was 720km out of tank.....

My last car..an eb wagon got 820 km out of a tank to Queensland average.

**Stav** · 12-07-2008, 05:20 PM

Quote:

Originally Posted by T3man

Heheheh Stav, I just read your other thread about going the supercharger route. Better decide first up what you want mate - power or economy. Because what you were talking about doing to your car with supercharger is NOT going to give you the economy you are looking for. You can't have the best of both - but you can get a good compromise if you build the engine right.

And, if it's a fuel cost/km issue you have, then the aswer is very simple - dedicated LPG. It will work well with supercharger or turbocharger installations and cut your fuel bill by 30% to 40% over what you are getting now and you will still have power to burn.

Supercharger is on the cards and you can get great economy if you are careful and not on boost much.Pay as you go is the rule.The faster you go the more youpay.

T3man · 12-07-2008, 05:23 PM

Quote:

Originally Posted by Stav

I have 4:11 gears . Haltech is very tunable to take some more fuel out. I want to take this to a safe lean mxture for daily driving and my logic for water injection is to keep the engine cool for even leaner mixtures.I dont want to burn the valves etc.

If you want to keep the 4.11 diff then you need to start looking for a double overdrive gearbox like a T56 - you will get a 20% improvement in economy straight up without touching your tune. But the box conversion is going to be around the $7500 region I imagine.

ratter · 12-07-2008, 05:24 PM

Why arn't you using closed loop?

Does the Haltech support it?

Don't bother with cruise mixtures at that range, go straight to 14's.

Some factory ECU's used to support lean cruise, which would run in the 17's on light throttle cruise, but you have to have plugs and timing to match the settings.

T3man · 12-07-2008, 05:25 PM

Superchargers don't work that way mate - you pay for boost ALL the time with a supercharger because they are directly engine driven - which is why 90% of manufacturers go the turbo route - power/boost is on demand just like you want it.

ratter · 12-07-2008, 05:26 PM

Supercharger will hurt economy, as it uses horsepower to turn it, even when off boost.

**Stav** · 12-07-2008, 05:39 PM

Quote:

Originally Posted by ratter

Why arn't you using closed loop?

Does the Haltech support it?

Don't bother with cruise mixtures at that range, go straight to 14's.The
Some factory ECU's used to support lean cruise, which would run in the 17's on light throttle cruise, but you have to have plugs and timing to match the settings.

The mixtures on my car go to 11 odd in that range .If they did go to 14 it would be great.The engine work to the wagon made the standard computer have a fit and so I transplanted the piggyback.My car would not idle on stock ecu alone.Afuel ratios if it did start were around 9.9 to 10 everywhere.

Haltech is a piggyback. Bummer about the supercharger.Still for that sort of power at least I am going to be getting some serious fun out of it.

ratter · 12-07-2008, 05:50 PM

Stav, if the Haltech stops closed loop operation, I don't think it is going to be able to control what you want it to do.

I'd be surprised if you can't control it enough though.

Can the haltech control EGR?

You may have to get a flash tuner and use the factory control systems as late model factory computers can control a lot more than most after market ecu's

**Stav** · 12-07-2008, 10:41 PM

Closed loop operation is still active Ratter.At idle and light throttle it does seek 14.7 by the ego sensor. It does however need a nudge from the haltech to bring it into the ecu's range.

The edit is terrific.However the fact that I have to spend 2500 on top for tuning software of my own edit box after spending 1400 in the beggining is making the edits welcome far over extended . To add insult to injury it seems to trap me into forking out alot more money each time I make more modifcations.

The haltech has set me free to save money and make the wagon the best that I can make it.

ratter · 13-07-2008, 09:55 AM

If you are running A/F in the 11's you have a problem with either your tuning or the control of closed loop.

The car should pretty much always be operating in closed loop, except for warm up time and very hard acceleration.
Your base fuel map should also be configured in a way so this A/F happens without closed loop being used, this way your long term fuel trims are spot on and if you have a sensor fail it will still continue to operate correctly.

You also have to remember that there is a lot more to getting great fuel economy, rather than just leaning the mixture out.

5.0 ED · 13-07-2008, 01:15 PM

that is not necesarilly true that a supercharger will hurt your fuel economy, we have gained economy with supercharging using the same comp, obviously not full throttle thou. Also years ago i was speaking to a guy from capa and he was telling me that with their powerdyne kit for el they were getting nearly an extra 100km to a tank, his reasoning was that on the downstroke of the piston it is pushing it down rather than having to pull is down, i believe it has more to do with the disruption of intake air entering the engine causing it better mix with the fuel.

My brother install one of those toyota superchargers on a crossflow efi engine, and gained approx 50km's to a tank. He then put on a T3/T4 hybrid turbo and gained about another 50km's per tank.

On my EA that i turbo'd (i know its not driving off the crank but still) i went from getting 450km's to a tank on lpg to just on 600km's a tank.

HLC · 13-07-2008, 06:05 PM

i get between 450-550 out of a tank. thats combined city-highway and i drive my car like i stole it.

but its stock. aside from exhaust/xr6t snorkel. lately my economy has been around 12L/100km.

i would suspect a car with a bit of engine work etc purely in city driving would not get econony that good.

**Stav** · 13-07-2008, 08:51 PM

Quote:

Originally Posted by HLC

i get between 450-550 out of a tank. thats combined city-highway and i drive my car like i stole it.

but its stock. aside from exhaust/xr6t snorkel. lately my economy has been around 12L/100km.

i would suspect a car with a bit of engine work etc purely in city driving would not get econony that good.

I am going to try for 650 out of a tank for the fun of it..

GSH · 14-07-2008, 02:11 AM

Well on my AU2 XR8 (read sig for minor mods) i spend about $350 a month and i get about 320kms out of the 68L tank...and i never go easy on it...always have it atleast quater/half pedal on take off....i dont drive it easy.....I got 550kms when i was driving to see a mate 750kms away.....Thats over taking road trains and stuff and getting up to like 180 when over taking them big suckers.....If you drive it nice around town and give it a bit here and there you can get 420-450kms, 500kms if you an aboslute nanna i rekon.

My best was 420kms....Thats not really being a nanna though.

Sox · 14-07-2008, 06:11 AM

Listen to Ratter and T3man, they're right, you're running to rich at part throttle.
Ditch the Haltech, your engine doesn't need it. You're making similar power to what my XH did and I used a standard XR ECU. AFR's were spot on all the time and I got over 100k more than you with well over 700k on the highway, and I never chased economy, that is, I drove it like I stole it.

A supercharger will use more fuel, no question, you can't have it both ways.
And you won't get 1000k's to a tank with your config, ever.

BTW, regarding the other thread, if you do end up going forced, a turbo is a much more elegant solution than a supercharger.

**Mechan1k** · 14-07-2008, 07:31 AM

Stav if you want cheap running with a lot of torque.

Convert it to LPG (Sequential Vapour Injection) ... and then run boost ... the ONLY way.