Tuned N54 @ altitude running 'rich' at the coast?

[fusion01]

Hi all, title sort of says it all. If a tune (software map, stage 1) was applied in Johannesburg would the car then recalibrate at the coast automatically or could it continue to run as rich, leading to heavier fuel consumption? Good run last night with my N54 and saw 17.5 litres per 100km's. Hey, I've seen 33.3 litres per 100km's on the track and that was at around 20 degrees C, all @ sea level. Kinda freaky. Stock GTI MK5 never more than 21.28 litres @ the track (huge difference). Is the tune leading to increased fuel consumption? I'm freaking out a little here and would appreciate some advice.

 

[Twinz]

I think Rolf and Sherwin are the best guys to answer that. :thumbs:

With a piggyback tune we recommend an adaptive map which calibrates to the change in conditions. :thumbs:

 

[fusion01]

Maybe someone can chime in here as to whether this sort of fuel consumption is quite the norm for the N54 stock? I say this as I bought the car second hand quite some time ago with the map supposedly removed beforehand (I specifically asked for this). Then I got dyno'ed here @ the coast: 240kw / 480nm at the flywheel which had me think map was still loaded. I actually had a dealer under MP specifically hunt for software - they found none. So I'm not even sure at this stage if I have one or not...!

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I think Rolf and Sherwin are the best guys to answer that. :thumbs:

With a piggyback tune we recommend an adaptive map which calibrates to the change in conditions. :thumbs:

Thanks, I emailed the tuners this am with no reply, so hoping I get one - also relying on the expertise and helpfulness of others on the forum. Cheers

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With a piggyback tune we recommend an adaptive map which calibrates to the change in conditions. :thumbs:

And if one didn't have an adaptive map loaded, then what sort of % estimate might one face with regards to a possible fuel increase? I know it's hard to be precise based on variables such as the tuner, the map, the car's mileage etc so not looking for absolutes here, just some sort of generalisation if possible

 

[Josh-ZN]

sounds like either a strong stock or an x35i with bmw performance pack or a very weak left-behind tune.

an x35i is very very very thirsty. i have gotten used to terrible economy but the pure joy of acceleration is worth it :rollsmile:

 

[Raybimmer]

The track consumption is heavy as you are basically using full throttle all the time , I would expect mixtures not to lean out at full throttle,the richer mixture is cooler than a lean one ( cooler mix =more mix ) .

Even my old e34 540i gives high 20's when doing some exhaust cleaning ..:roflol: ....thats the price for getting cobwebs out .

 

[SP33DYV]

Last week Thursday I got a 335i to test drive over night. I had the fuel consumption up to 36l/100km in a flash. This was an N54 - 2008 model and I doubt it had any software. I had to add fuel after just 64 km on a quarter tank. I had lots of fun though.:rollsmile: The power is addictive!

 

[fusion01]

Thanks for the input guys, really appreciated and why the forums are great. I was told by the BMW dealer upon collection after they'd run tests that it simply was a 'very strong N54' but I kind of put it down to them not finding a tune. Now I'm not so sure and based on Josh's comments it's quite likely true. Obviously good news.

What I just find interesting is that I always thought a larger displacement engine would take less 'strain', consuming less fuel under load in proportion to a smaller displacement engine. I was wrong if one considers that at the track the Golf 5 GTI was getting more than 50% further per km:

- N54: 3k p/l
- BWA: 4.7 k p/l

However I've found the average percentage decrease on a spirited run (7/10's) between both cars as it relates to manufacturers claims vs real-world consumption to be a ~40% reduction. And the consistency is what goes some way to answering my initial query.

Obviously topography plays a part in fuel consumption and one will burn a fair amount of fuel traversing uphill. Then obviously less on the downhill. But even considering the latter (and gravity taking its part) you'd still consume more than if covering flat ground? In other words, one would consume more in proportion uphill than one would save on the downhill (when not coasting). Correct?

I'm still not 100% sure about the query relating to running a richer map for altitude when down at the coast, or whether the MAF etc recalibrates so as for this to be a zero-issue as it relates to any fuel consumption increase. Maybe a reputable SA tuner could chime in here. Still no reply to my email sent yesterday morning and I'm most curious.

 

[Andz]

jis my 2c with my Xcede chipped n54 to durbs

drove str8 into durbs...added a can of OB en dyno'd
jhb made 260wkw....@ WRC
@ autotrix i made 272wkw's

power was up...en the fuel consumption was about the same as it was in jhb
the x35's are thirsty cars....
on the drive down i was ave'ing 8.4L per 100
town driving in jhb en durbs was bet 13-18L per 100
not sure wot i did on the sprited drives....lol

 

[fusion01]

jis my 2c with my Xcede chipped n54 to durbs

drove str8 into durbs...added a can of OB en dyno'd
jhb made 260wkw....@ WRC
@ autotrix i made 272wkw's

power was up...en the fuel consumption was about the same as it was in jhb
the x35's are thirsty cars....
on the drive down i was ave'ing 8.4L per 100
town driving in jhb en durbs was bet 13-18L per 100
not sure wot i did on the sprited drives....lol

That's only like a 4.5% power loss @ altitude (12 kw's) - impressive. Ok so if you're averaging 15.5l per 100km's that's around 6.5 km's per litre. Then my 8 km's urban with a bit of a heavy foot but no heavy traffic seems about right. Just quite shocking with turbo's how putting foot just means the Big Suck.

Another thing. Reset the trip computer while at a standstill and watch the fuel consumption figure. Car idles at like 2-3 km's per litre. No wonder after a trip to the dealer it takes a beating - I think they leave the cars idling for a long time, why I don't know.

Aynway, thanks for your input Andz[/b]

 

[Andz]

no probs fusion.....