Fuel Economy with Tune

[whplash]

Thinking of getting the APR stage 1 tune for my 2006 GTI.
I have seen all the dyno figures etc but what has it done to your fuel economy? What is the real on road economy?

[h100vw]

I'd say that would be totally down to your driving style.

You can't use the extra power all of the time but you could expect to use a little extra fuel in reality.

Gavin

[blutopless2]

like all things to do with fuel economy there are heaps of things that can influence it. driving style, tyre pressures, vehicle load, air con on, windows open etc etc etc....
having said that i consider my driving style to be pretty sedate. I drive a Jetta TSI that has been chipped to approx 182kW. It is a family car that i use to and from work with a baby on board most of the time.
When i bought the Jetta i did some fuel consumption checks on it for the first 10,000k's. The average was between 9-9.5L/100k's doing a mixture of freeway and suburb driving.
After chipping doing the same driving it averaged between 8-8.5L/100k's with it regularly sitting on 8L.
I just got back from a trip to queensland doing a round trip of 4500k's. It averaged 7.5L/100k's for the entire trip - fully loaded with 3 adults & toddler and a boot packed completely full of luggage with the air con on nearly the entire time - with the freeway sections getting down to 7L/100k's.
Its how you drive it. sedate will see improved fuel economy, thrash it and of course it will guzzle worse than stock.

[Nardi330]

what i find is that after bluefin, around city is now 12L/100km where previously it's around 10L/100km. but on highway it is more efficient after the flash.

[gtimk5]

With just the reflash I acheived much better figures especially on the open road where I was averaging 7.1 on trips up north of around 200 kms.
when I change the exhaust and fitted the appropiate program I get approximately 7.9-8.1 per hundred these days on longer trips.
Around town or actually going to/ from work I average 9.1 per hundred but it varies as to how much stop start traffic there is.
Andrew

[anarchycamp]

I found the APR reflash made my fuel consumption slightly better in day to day driving.

When I am giving it a bit I don't really care about fuel consumption

[Guest212]

I found the APR reflash made my fuel consumption slightly better in day to day driving.

When I am giving it a bit I don't really care about fuel consumption

And to build on this, if you do care you are obviously are too tight and should sell the petrol and buy a diesel.

[bj240z]

Thinking of getting the APR stage 1 tune for my 2006 GTI.
I have seen all the dyno figures etc but what has it done to your fuel economy? What is the real on road economy?

I cant tell you that my partner gets better economy out of the car then what i do, but i didn't buy to because I wanted a cooler earth. If consuming more fuel is a concern, then don't get it, cause as soon as you want to "play" you'll be dumping more fuel into the system, then what you would have in stock.

2 cents!

[G-rig]

I agree, fuel economy is as good as your right foot!

[datracer99]

An edited excerpt from my previous post on why a chipped car might give better fuel economy in day to day driving...

Most cars make their peak torque well below peak power, and torque normally drops off substantially as revs rise.

Logic tells me that the point at which the engine makes peak torque is probably it’s most fuel efficient. The AFR generally doesn’t change much over the rev range, so up to a certain point we are getting more torque for the same air fuel ratio. After this torque starts to drop away.

This is possibly due to less time for complete combustion as revs rise, as the gasses have less time to get in and out of the combustion chamber at higher revs. As revs rise torque is falling away as efficiency drops.
Power continues to climb, as power is a function of torque and the number of engine cycles - i.e how many times the torque is applied to the crankshaft.

So if we get a new tune that increases the mid range torque, and therefore we use WOT less, then we spend more time where the engine operates at it’s greatest efficiency, and therefore we use less fuel.

I'm still waiting for a mechanical engineer or automotive engineer to shoot my theory down with science if I’m on the wrong track.

So, if you don't change your driving style after you get chipped then you may get better fuel economy.

[blutopless2]

So, if you don't change your driving style after you get chipped then you may get better fuel economy.

definitely improved for me.

[locosam]

I dont know that much about golfs, but i know a little about turbo's. although im not an engineer of any kind.

The reason you get better fuel economy (assuming you drive in the same manner) is because usually when they tune, they lean the mixtures out and advance the timings. this means, less fuel being used for more power more or less.

the reason golf doesnt tune their cars in the same way is because a bad batch of fuel might ping the engine too much, causing detonation and possibly putting a cylinder right through your block. they need a bit of tolerence to keep the engine safe. also, when your engine is making more power, it wont last the same amount of time as it does when its stock. vw dont want to keep on replacing engines because they tuned every single last kw out of the engine

An edited excerpt from my previous post on why a chipped car might give better fuel economy in day to day driving...

Most cars make their peak torque well below peak power, and torque normally drops off substantially as revs rise.

Logic tells me that the point at which the engine makes peak torque is probably it’s most fuel efficient. The AFR generally doesn’t change much over the rev range, so up to a certain point we are getting more torque for the same air fuel ratio. After this torque starts to drop away.

This is possibly due to less time for complete combustion as revs rise, as the gasses have less time to get in and out of the combustion chamber at higher revs. As revs rise torque is falling away as efficiency drops.
Power continues to climb, as power is a function of torque and the number of engine cycles - i.e how many times the torque is applied to the crankshaft.

So if we get a new tune that increases the mid range torque, and therefore we use WOT less, then we spend more time where the engine operates at it’s greatest efficiency, and therefore we use less fuel.

I'm still waiting for a mechanical engineer or automotive engineer to shoot my theory down with science if I’m on the wrong track.

So, if you don't change your driving style after you get chipped then you may get better fuel economy.

[G-rig]

^That sounds fairly logical. The extra heat will shorten the life but to what degree i'm unsure, and is probably 'ok' and most people wont keep the same car for over 10 years, however there are early MK5's that have done a lot of km after being tuned with no worries. Safe to say it's fairly harmless as they are quite detuned to start with. Should also add it's done so they still run and are reliable in bad conditions/environments.