Benefits of "chipping" / Remapping - Worthwhile?

[romeogolf]

I've only heard of and learnt about remapping cars since reading online here, so please forgive any ignorance!

Current car is a new C-Class C220 diesel. Majority of driving is during rush hour on a mixture of 80% motorway/A routes and 20% slow moving city driving. I'd be interested in knowing if something is available to improve fuel efficiency (currently getting 52mpg on average over first 3,000 miles in the car).

I've read that often the tweaks made to improve efficiency also boost power at lower engine speeds and save the fuel by preventing needless down changes, is that correct?

Where do you start to look to find the right product for you? What should I be looking for? And what other benefits or drawbacks are there? Is it worthwhile?

Thanks

[PHCorvette]

Mostly snakeoil.

[daemon]

PHCorvette said:

Mostly snakeoil.

No

Use a reputable company and you will get the gains that they suggest - usually around 20%

[Sheepshanks]

I've got a different model of Merc diesel but am active on the Merc forums and 52MPG for the use you describe seems pretty amazing.

As economy seems to be the most important to you then I'd leave it alone. Most people map their cars to get more power/torque and better throttle response.

Be aware that MPG figures on the trip computer can be way out after a car is mapped as the figure is calculated from injection pulses - it doesn't measure fuel used at all.

[300bhp/ton]

romeogolf said:

I've only heard of and learnt about remapping cars since reading online here, so please forgive any ignorance!

Current car is a new C-Class C220 diesel. Majority of driving is during rush hour on a mixture of 80% motorway/A routes and 20% slow moving city driving. I'd be interested in knowing if something is available to improve fuel efficiency (currently getting 52mpg on average over first 3,000 miles in the car).

I've read that often the tweaks made to improve efficiency also boost power at lower engine speeds and save the fuel by preventing needless down changes, is that correct?

Where do you start to look to find the right product for you? What should I be looking for? And what other benefits or drawbacks are there? Is it worthwhile?

Thanks

Remaps can be useful and you may see mpg gains and performance gains, depending on what you are after. But tbh, if all you want it for is mpg gains and you are already getting 52mpg, then I'd say it's probably not worth it.

Gains won't be massive and the cost offset means it'll take a long time to even recoup the money. Not too mention the insanity of buying a new car that depreciates like a rock then worrying about a couple of mpg fuel saving for cost reasons. That's just completely mental and you really should get your head checked

If it's a new car, then there could be warranty implications to remapping.

[Lazadude]

More power, better drivability (Curve is changed), and the same MPG if not more.

Find a decent company though, and avoid the plug in boxes.

[Pablo16v]

Not apples for apples but I had a 140bhp Passat re-mapped to just over 170bhp, with similar percentage increase in torque, and while the performance increase was noticeable it made virtually no difference to the economy. Approximately 2 mpg based on trip computer readings.

[willmagrath]

i had it done on my fabia vrs, 130 to 175hp from Revo. Completely changed the car! still gets 62mpg on a run as well. It does however mean that the clutch started slipping earlier than it should have but that was at 100,000 miles on the first clutch...

[romeogolf]

Sheepshanks said:

I've got a different model of Merc diesel but am active on the Merc forums and 52MPG for the use you describe seems pretty amazing.

As economy seems to be the most important to you then I'd leave it alone. Most people map their cars to get more power/torque and better throttle response.

Be aware that MPG figures on the trip computer can be way out after a car is mapped as the figure is calculated from injection pulses - it doesn't measure fuel used at all.

I log it at re-fills using an app on my phone. Surprisingly the trip computer in the car reads an average of 52.3mpg and my phone shows 51.62mpg - I would have expected a much larger over-read from the car.

[SPRocco]

Something to note regarding "new" - New to you or new car?

Warranty could be affected by remapping

[romeogolf]

SPRocco said:

Something to note regarding "new" - New to you or new car?

Warranty could be affected by remapping

New car entirely. Good to know about warranty. I've heard that it's removable "without a trace" in places, but not sure what truth there is to this.

[romeogolf]

300bhp/ton said:

Gains won't be massive and the cost offset means it'll take a long time to even recoup the money. Not too mention the insanity of buying a new car that depreciates like a rock then worrying about a couple of mpg fuel saving for cost reasons. That's just completely mental and you really should get your head checked

Hah, yes, it's not cost. I just take some weird satisfaction in seeing high average economy. Gives me the warm fuzzies.

[SPRocco]

romeogolf said:

New car entirely. Good to know about warranty. I've heard that it's removable "without a trace" in places, but not sure what truth there is to this.

I think the without a trace part is questionable.. IIRC Revo state on their website (VAG okay but same topic) that the software change can be picked up by the main dealers even if the map isn't active?

Happy to be corrected on that one mind

EDIT: found some info that might interest you on a few points, looks like I'm wrong about the dealer

https://products.revotechnik.com/products/faq.aspx

Edited by SPRocco on Thursday 12th November 13:09

[anonymous-user]

If all you want it for is economy then personally I say don't bother. Let's say you get an extra 5mpg from where you are now out of a remap which is very optimistic IMO.

Assuming 20k miles a year that saves you £12 a month at current fuel prices. You're looking at well over two years just to break even on any sort of decent remap. Taking the potental warranty implications into account it doesn't make sense to me.

If you want the extra performance too though, fill yer boots

[devnull]

Do brabus offer a tuning box for this? They did for my CLK 320cdi, it was a tick box option from new. However, it did cut the warranty from 3 years to 1.

[tezzer]

Did my daughter's mini 1.4D and the transformation was incredible. Much punchier, cruises comfortably at much higher speeds, the downside is that doing so increases fuel consumption, of course.

Superchips time was £320 but yeah, I'd recommend it.

[Willy Nilly]

It'll be mega. Defo. Merc have no idea how to calibrate engines and chuck what every fuel they like in the engine and hope for the best. They certainly won't have bother investing 10's of millions of quid on labs to test their cars in or bothered testing them at altitude or in cold weather or in hot weather. You're bound to get huge gains buying a chip or map off a bloke from the internet.

What to buy some beans?

[Ozzie Osmond]

... and I've got a magnet which goes around the fuel line and increases my mpg by 10%. It's extraordinary that the manufacturers don't adopt this technology themselves - I think they must be in league with the oil companies to make sure demand doesn't fall.

[Blanchimont]

I had my turbo petrol car done, and saying it uses less fuel is balls.

I get exactly the same when not got my foot in it as I used too, but it is a lot more punchy on boost. It depends on what you want, increased fuel economy is something it won't do, not without reducing power which is counter intuitive.

[Gallen]

remaps - yes, but also consider decent tuning boxes - I have used many and over many miles (so consider ignoring those who "wouldn't touch them").

I would recommend DTUK (no affiliation).
Moreover very impressed with the unit I had from them which totally transformed the car as if I had unhitched a caravan off the back. It also improved fuel economy and drive.

G.