Does a remap increase MPG or not?

[bigdavevw]

Hello, yes i have searched but i cant find a definitive answer.

I have an A3 1.8t AUM, fully standard apart from a 007. I would like a bit more poke from the car, but i dont want to change the exhaust/air filter to a cone, as i like how quiet the car is.

The companies i have looked at all say you will get more power as well as more mpg, but they would say that as they are trying to sell you something.

Any help would be great.

Dave

 

[Paul_A4_UK]

From my understanding, and experiences over the years, whenever you tune an engine to get it running 'just right' you end up with better mpg under normal driving circumstances but worse mpg when making progress. This has been the same for me on all my motorbikes and my last car which was cammed and remapped.

The big question is how long is the payback period, as in the savings you make through mpg over the price of the mod. I suspect it will be a fair few miles so in reality I wouldn't really be too concerned about mpg. Just a remap though should not see your car run any worse and should liven the drive up a bit with a few more hp and ft/lb of torque

 

[Paul_A4_UK]

I'm also in the same situation as you with regards to the exhaust but I believe Miltek do a larger bore exhaust and resonated boxes so it isn't any noisier than standard, at least they do for my car (A4 B6), which I would assume would allow the gasses to flow a little more freely. I had a very loud exhaust on my last car (Blueflame) and that droned like hell on the motorway. I do not want that to happen with this car. I'm unsure how loud an un-resonated exhaust is but as we have a turbo this also helps to cut down on noise a little.

I just need to get the gaps in my rear bumper filled as the standard pea shooter exhaust just doesn't do it well enough.

 

[Brodster]

In a word yes it does. Due to the increase in torque your engine revs reduce so therefore there is an increase in MPG under NORMAL driving conditions. After a remap the way you drive is relative to how much power you have under the right foot so alot of people dont see an increase but rarely do they see a drop in mpg.

 

[@udi A3]

My tdi made very little difference, map makes it drivable, but kicks out smoke top end of the rev range which of course isnt good for mpg. Certainly didnt lose mpg, and i see around 55mpg average using v power, and about 44 with non v power.

 

[Paul_A4_UK]

Is the difference that much on diesels when using V-power over non v-power? that's a considerable difference. Wish it was that much for the petrol too! I'm only on my second tank of V-power and only have one tank of normal to compare with. Unsure what the pervious owner run it on, I'll ask him but I suspect just run of the mill stuff.

 

[@udi A3]

The v power is more noticable when you have fun 3-4 tanks through, ive started filling 50-60% at a time .
When going back to normal fuel the difference in power and running is noticable. but yes it makes a huge difference in my car, never really noticed it with petrol cars, but its probably all about the software to make use of the fuel.

 

[myke]

After a more power remap in any manual turbo car, you will get more MPG as soon as you try to get the most MPG, not the quickest x-y mph out of your new racing car.

 

[HibiscusS4]

It depends on the map, there is no fixed answer. More torque does not equal more mpg if there is more fuel used to get that torque. You will only see a benefit in MPG if the car is mapped to run leaner at certain RPM's which some tuners will do to give you a best of both worlds map.

 

[Jackie Brown]

Petrol Turbo will NOT increase MPG!!!!

How can you get more power like this? Yes they run 'lean' as standard - you should purchase VCDS and 'log' this 1.8T fuelling (if you can - these are not all wideband), then monitor fuelling with remap and see what happens.


Speaking of turbo diesel - when you mess with 'rail pressure' (which I am personally against), or adjust 'injection duration' map(s) the MPG display will be even more out of sync than the original software. The little display on instrument cluster is just a guide, it guesses, and constantly changes because it is just a toy.

For real world MPG test please fill your tank to the brim 3-4 times and reset the 'trip' counter. Do the same after remapping and see what MPG you really get. For mature drivers they stay around the same - to make a Turbo Diesel quicker we use more fuel. Smoke should not happen IMO, it is too much fuel (I would pull back slightly at higher RPM for the person with smoke there - but depends on the customer/their budget etc).


With petrol turbo - you cannot expect to tune for more power and not see increase in fuel consumption.

Most throttle (fuel) LAMFA request lambda 1 in these 1.8T (14.7.1 AFR <-- very LEAN for petrol turbo, but working 100% from factory). After this we have 'actual' fuel KFLBTS lambda for component protection (if 'throttle' request is not good enough, different engine conditions) dropping very low maybe lambda 0.7 (10.2-10.4 AFR <-- TOO RICH FOR THESE ENGINE!! But manufacturer do for protection)


Try to think at 100% throttle, most of these petrol turbo are requesting 14.7.1 AFR. Very lean! You cannot modify this engine without REDUCING lambda, which INCREASES fuel!!!

Lambda 1.0 = 14.7.1 AFR (some say 'optimal' for engine power/torque under certain conditions)

Lambda 0.9 = 13.2 AFR

Lambda 0.8 = 12.2 AFR

Lambda 0.7 = 10.2 AFR (too much fuel in 'some' engine and lose power)



Who is promoting MPG increase on engine? The day I see an 'economical' remap that is true, I will donate my programming tools to charity and become a prostitute.

I attach 2.0TFSI K03 197hp 'log' with modify software ONLY, no engine mods. Ignore 'specified' fuel look at 'actual' fuel to see where 0.828 lambda, shows 0.83 from 4000RPM to redline, 100% working, 100% good enigne. You will notice load request very 'close' to actual, with boost very close to request! I can reduce LDRXN (load limiting) from 4000RPM upwards because the engine is not giving as much here you see

 

[shady-ninja]

ive had two petrol turbo charged cars remapped in the past and there is no improvement in MPG coz your going to be spending most of you time revving the nuts out of the car.
on diesel cars it moght improve things a bit, especially on the motor way.

 

[k1ano]

Sorry posting takes out all spaces for some reason :-( Anyway ... IMO a remap will simply provide the opportunity to change your driving style which may or may not mean improved MPG but more likely reduced - because after all if you do it for more power then you will use more fuel ... Take say one example with an unmapped car, where you may drive more aggresivley in terms of throttle position and gear to overtake or reach desired crusing speed this places different fueling demands than say a more moderate throttle position which could be achieved on a mapped engine and even more-so with an engine tuned for improved volumetric effeciency with improved induction, charge cooling and exhaust. A power map, without say other tuning changes, will also likely increase charge temperatures which reduce efficiency and so will also cause increased MPG. An engine is a balanced system so simple binary answere are not clear cut but I do agree that if you tune a car or map one or both you shouldn't expect better MPG but you can achieve good MPG simply through a change of driving style.My car has a a number of modifications which mean it delivers more power and is very quick but I can see over 41 mpg on the trip easily and maintain an average of between 36 and 39 mpg now and drive generally normally with odd bursts but never leather it everywhere ...Martin

 

[bigdavevw]

hey thanks for the replies guys! i will defo get on at some stage then. Wanting to get the car running sweet before i remap it tho

 

[Audi Dynamik]

I found with my remap if you drive it hard it will use more than it did before but if you take it easy it will do more than it did before.

 

[Brodster]

Im not gonna start an argument here as Ive been running my mapped S3 now for 18 months and I know its getting about 30 MPG calculated.......and if anyone wants to argue then be my guest. My last S3 when standard was getting about 26MPG. I do combined rural and urban driving with a 410 mile round trip every month at a steady speed......not slow and not too fast so yes my 30MPG is spot on.

 

[Audi Dynamik]

Im not gonna start an argument here as Ive been running my mapped S3 now for 18 months and I know its getting about 30 MPG calculated.......and if anyone wants to argue then be my guest. My last S3 when standard was getting about 26MPG. I do combined rural and urban driving with a 410 mile round trip every month at a steady speed......not slow and not too fast so yes my 30MPG is spot on.

No arguing with me fellar
I am just saying what i have found with my remap.

 

[Brodster]

No arguing with me fellar
I am just saying what i have found with my remap.

Wasn't directed at you Buddy. Sorry if it looked like that but it wasn't meant to. I just cant stand people sticking their head on chopping block when there is evidence that contradicts

 

[Mollygoogle]

I've had mapped two xr3i's (mk4 & mk5) and a 220 GTI which all returned less mpg. I've had mapped 2 impreza WRX's which both returned more mpg. I've boxed or mapped a 1.9 Passat, a 1.9 Golf, a 1.9 Audi and a 1.9 Astra all of which have returned more mpg, especially the Astra which returned ridiculous improvements. All mpg gains were long term calculated, brim to brim over thousands of miles

 

[TDI-Tuning]

Hi All, Just thought i'd throw out there the suggestion of giving a 'method' of tuning a go and see what you think, I fully agree brim to brim is the clear test and to ignore the MPG computer. We see some fantastic MPG gains on various vehicles but you do need to spend the time optimizing the software configuration.

 

[Jackie Brown]

Brodster was probably talking about me.


I would like to meet some 'tuners' at an airfield/rolling road/track and see who can actually tune these engines without using the internet/email/ebay/middle man.

I am not singling any one company out here - I know Rick at Unicorn Motorsport/Motor Development whatever understands these cars more than myself (i am very basic simple knowledge) but I would love to see my local Superchips 'dealer' turn up and modify software on their own.

<3 (love heart)

 

[Jackie Brown]

I agree with TDI Tuning with filling tank to the brim, and ignoring the trip counter. Especially after tuning/fiddling.


With the tuning box we are playing with Rail Pressure signal - and the MPG display will look very good after fitting


But you are 100% correct and honest with your advice x