Diesel tuning chips

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Pale Rider

Legendary Member
Fuel consumption improved by 3-4mpg after I had my last diesel car remapped.

I didn't use the extra a grunt a lot, but I did use it.

So done properly, a remap can be a win/win situation.
 

400bhp

Guru
[QUOTE 290426, member: 9609"]I think this police officer would prove you wrong
LINK


Most aspects of tuning is all about making an engine more efficient, so potentially more MPG. however as better enging efficiency also gives greater power outputs then in most cases the vehicle will be driven just that little bit quicker so any increase in mpg will be lost.
In any case if you want to tune up or make a modern diesel engine more efficient, the first steps need to be getting rid of all the anti-pollution crap like DPF, EGR, adBlue etc[/quote]
Prove me wrong, how? 140 Isnt a sign of anything special, nor is it a sign it was a diseasel.
 

Smurfy

Naturist Smurf
[QUOTE 2907426, member: 9609"]Most aspects of tuning is all about making an engine more efficient, so potentially more MPG. however as better enging efficiency also gives greater power outputs then in most cases the vehicle will be driven just that little bit quicker so any increase in mpg will be lost.[/quote]

I'd agree with that. I think the driver needs a lot of self control to make use of the improved efficiency. I'm willing to bet that most turbo diesel car drivers achieve lower fuel efficiency than normally aspirated diesel car drivers. The difference between the two in the officially published fuel efficiency figures isn't that much, and the temptation to step on it is too much for most TDI drivers (just watch the way Audi A3 TDIs are driven!).
 

GrasB

Veteran
Location
Nr Cambridge
I'd agree with that. I think the driver needs a lot of self control to make use of the improved efficiency. I'm willing to bet that most turbo diesel car drivers achieve lower fuel efficiency than normally aspirated diesel car drivers.
That's a given as turbo diesel engines are burning a lot more air than N/A diesel engines. However to get the same power out of an N/A diesel as a turbo diesel the engine would be huge & burn much more fuel.

The difference between the two in the officially published fuel efficiency figures isn't that much, and the temptation to step on it is too much for most TDI drivers (just watch the way Audi A3 TDIs are driven!).
... so explain why drivers over & over again report that remapping not only gives more power but also improves their fuel economy. Also the difference between 16.2mpg & 15.7mpg for a few seconds (WOT 50-80mph in 5th) will pale into insignificance compared to 58.4mpg compared to 67.4mpg (70mph cruise) for several hours. That's taken from a BMW 320d map & published CdA/Crr data.

IIRC most 'basic' remaps for turbo diesel engines actually use no more fuel than the original maps they simply allow more air into the engine.
 

Smurfy

Naturist Smurf
58.4mpg compared to 67.4mpg
That differential sounds much too large. Is it a bonafide with-without turbocharger comparison for a vehicle that is otherwise exactly the same?

These types of comparisons are getting increasingly difficult to make, as manufacturers are abandoning production of normally aspirated diesel cars. I've found some old data based on a standardised on-the-road fuel efficiency test. Same vehicle, same 1.9L engine, three different levels of Turbocharging, and Normally Aspirated:
130bhp Turbocharged - 62.8mpg
http://carfueldata.direct.gov.uk/search-new-or-used-cars.aspx?vid=212997

100bhp Turbocharged (Pumpe Duse) - 64.2mpg
http://carfueldata.direct.gov.uk/search-new-or-used-cars.aspx?vid=212995

150bhp Turbocharged - 64.2mpg
http://carfueldata.direct.gov.uk/search-new-or-used-cars.aspx?vid=212994

68bhp Normally Aspirated - 64.2mpg
http://carfueldata.direct.gov.uk/search-new-or-used-cars.aspx?vid=212998
 

asterix

Comrade Member
Location
Limoges or York
I can't believe this discussion has got this far without anybody mentioning insurance. If you had an accident and needed to claim and - unlikely, I know - your insurer discovered your car was modified for extra performance they would refuse to pay out, since insurance companies will always look for a reason not to pay. If, God forbid, you or somebody else were badly injured, you would end up footing the bill for healthcare and rather regret having wanted to boast about having taken a couple of seconds off your car's 0-60 time. Then there's the legal aspect of driving without adequate insurance cover.

Most executive cars nowadays have sufficient performance for UK road conditions; my previous Audi A4 and current Passat 2.0 tdi with around 140 bhp will get you away from the lights fast and, oh yes.... give you that extra power for emergencies that seems to worry car performance obsessives.

TBH my new Toyota Yaris copes perfectly well with normal driving. Most of its mileage has been clocked on trips between 80 and 200 miles.

Low fuel consumption, insurance rock bottom, cheap excise duty.
 

green1

Über Member
I've just ordered one of those magical chips that will get 30mpg out of my car. :rofl:

Only way to get that out of my car is to stick it on the back of a lorry. :whistle:
 

green1

Über Member
[QUOTE 2907138, member: 259"]That's interesting - the 'standard' BHP is set to 136 in Belgium (lower than in Germany for the identical car)[/quote]
There is the problem, there are that many different standards for HP that you often can't tell if your comparing apples with oranges or identical oranges.
 

ASC1951

Guru
Location
Yorkshire
Same here my average is 18mpg and that's driving granddad stylee
Serves you right, you planet vandal! ;)
 

Smurfy

Naturist Smurf
There is the problem, there are that many different standards for HP that you often can't tell if your comparing apples with oranges or identical oranges.
An orange is an orange!
square-orange.jpg
 

GrasB

Veteran
Location
Nr Cambridge
That differential sounds much too large. Is it a bonafide with-without turbocharger comparison for a vehicle that is otherwise exactly the same?
Nice way to take something complexly out of context which has NOTHING to do with the point you're trying to make. I was comparing the fuel economy for a 50-80 WOT acceleration run & then 70mph cruise on a 320d on factory map v's performance remap. It's perfectly correct as for the same power the injector duty is reduced by about 13%. In this case a 3% increase in fuel usage for 7.5s is countered against a potential 15% reduction in fuel usage for several hours... but actually a WOT 50-80 may use less fuel as Id guess that the remapped engine would reduce the 50-80 time by about 5%.

These types of comparisons are getting increasingly difficult to make, as manufacturers are abandoning production of normally aspirated diesel cars. I've found some old data based on a standardised on-the-road fuel efficiency test. Same vehicle, same 1.9L engine, three different levels of Turbocharging, and Normally Aspirated:
130bhp Turbocharged - 62.8mpg
http://carfueldata.direct.gov.uk/search-new-or-used-cars.aspx?vid=212997

100bhp Turbocharged (Pumpe Duse) - 64.2mpg
http://carfueldata.direct.gov.uk/search-new-or-used-cars.aspx?vid=212995

150bhp Turbocharged - 64.2mpg
http://carfueldata.direct.gov.uk/search-new-or-used-cars.aspx?vid=212994

68bhp Normally Aspirated - 64.2mpg
http://carfueldata.direct.gov.uk/search-new-or-used-cars.aspx?vid=212998
So you're comparing a 68bhp N/A to a 150bhp TD... what we need is a 150bhp N/A engine that'll be a 4.0 to 4.5l unit.
 

Smurfy

Naturist Smurf
Nice way to take something complexly out of context which has NOTHING to do with the point you're trying to make. I was comparing the fuel economy for a 50-80 WOT acceleration run & then 70mph cruise on a 320d on factory map v's performance remap. It's perfectly correct as for the same power the injector duty is reduced by about 13%. In this case a 3% increase in fuel usage for 7.5s is countered against a potential 15% reduction in fuel usage for several hours... but actually a WOT 50-80 may use less fuel as Id guess that the remapped engine would reduce the 50-80 time by about 5%.

Fair do, but why do automobile manufacturers expend huge R&D budgets working out how to make cars more fuel efficient, when all they need to do is head to the nearest back street remapper, pay £500, then interrogate the chip to discover the remapped settings?
 

asterix

Comrade Member
Location
Limoges or York
Years ago we'd a VW camper, 2l petrol that drank the stuff.

You could buy some device that you installed on the fuel lines and were supposed to magically give you a big up in the MPG numbers. It didn't, of course, but so far as I know no one got their money back.
 

GrasB

Veteran
Location
Nr Cambridge
Fair do, but why do automobile manufacturers expend huge R&D budgets working out how to make cars more fuel efficient, when all they need to do is head to the nearest back street remapper, pay £500, then interrogate the chip to discover the remapped settings?
The emissions thing isn’t quite correct in its analysation. I bought a 'pan-america emissions legal' turn key engine for my Ultima. It required about 15 hours of fettling to get it to pass on UK fuels, the emissions tests it was failing on it would have passed had I been buying US pump fuel. Most of the ‘factory approved’ remaps actually give better emissions with BS standard fuels than factory maps but if you take the car to another country then the emission levels maybe higher. This is because the exact fuel composition & additives change from country to country, even in the EU.

Also most remaps will not like low quality fuels - We all know that there are very few fuel refineries, so think Tescos super unleaded is as good Shell, BP or Esso supper? The more aggressive remaps will very quickly show that while the raw fuel is the same the additives put in cheaper fuels just aren’t as good. Some of the most aggressive maps actually will only work properly with a particular brand of UK fuel.

There is so much R&D tied in to getting cars through emissions tests under a very wide variety of conditions a lot of which the car will never see.

Oh yeah, on petrol engines, especially turboed engines, often you need to be more careful about keeping the coolant & cooling system in better shape as the engine will tend to run hotter.
 
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Smurfy

Naturist Smurf
The emissions thing isn’t quite correct in its analysation. I bought a 'pan-america emissions legal' turn key engine for my Ultima. It required about 15 hours of fettling to get it to pass on UK fuels, the emissions tests it was failing on it would have passed had I been buying US pump fuel. Most of the ‘factory approved’ remaps actually give better emissions with BS standard fuels than factory maps but if you take the car to another country then the emission levels maybe higher. This is because the exact fuel composition & additives change from country to country, even in the EU.

Also most remaps will not like low quality fuels - We all know that there are very few fuel refineries, so think Tescos super unleaded is as good Shell, BP or Esso supper? The more aggressive remaps will very quickly show that while the raw fuel is the same the additives put in cheaper fuels just aren’t as good. Some of the most aggressive maps actually will only work properly with a particular brand of UK fuel.

There is so much R&D tied in to getting cars through emissions tests under a very wide variety of conditions a lot of which the car will never see.

Oh yeah, on petrol engines, especially turboed engines, often you need to be more careful about keeping the coolant & cooling system in better shape as the engine will tend to run hotter.
Thanks for that explanation, it reminds me of my friend who owned a Honda CBR 600 which resolutely refused to run on anything other than BP petrol! It also sounds a bit like the business of making central heating boilers, where the manufacturer typically attempts to make the same boiler sell in as many markets as possible with as few boiler variants as possible. Similarly to road fuel, not all methane (natural gas) is the same, and the variations throughout the EU can be quite significant. I've considered buying one of these, and trying different fuels to see if I can tell the difference. Any thoughts on that? I'd be interested in a remap too, but I'd be a little worried that most insurers would decline cover, and once you've told them it sounds a bit fishy if you call back two days later and say you've restored the ECU to factory settings!
 
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