F30 (LCI) 340i M-Sport - ordered!

[JNW1]

Wills2 said:

People are also using corrected dyno figures on engines that self correct, there was a good article in a major german magazine autobild IIRC that showed when you didn't correct the figures on a modern turbo car the outputs were in line with the manufacturers figures.

I don't pretend to be anything approaching an expert in this but if an engine is self correcting on a rolling road that's presumably to allow for the fact that the air flow isn't the same as you'd get in normal road conditions (i.e. instead of the car travelling at 150mph it's sat stationery and relying on fans to provide the cooling instead?). In my simple mind that would tend to result in a lower bhp figure on a dyno compared to what you'd get on the road but if dyno users are then trying to allow for that by correcting their figures it has the potential to become a real bugger's muddle! However, if a car goes in for a remap - and has before and after runs done in the same conditions - presumably the difference between the two does at least give a reasonably accurate representation of what the remap's added?

[JNW1]

SelocMole said:

JNW1 said:

Also a fair point and if you can get the sort of terms SelocMole appears to have secured it's a cracking deal; would have thought a LSD alone would have cost well more than £1k fitted so one of those plus a remap and exhaust for less than £1k is an absolute steal in my book!

It is a fantastic deal - I am very happy - but got to stress this does not include the LSD sadly. Everything else, yes, but not the LSD.

Ah, thought less than £1k including an LSD sounded a bit too good to be true!!

[335d]

Wills2 said:

People are also using corrected dyno figures on engines that self correct, there was a good article in a major german magazine autobild IIRC that showed when you didn't correct the figures on a modern turbo car the outputs were in line with the manufacturers figures.

The problem I see with rolling road figures is that these tend to be small businesses where 99% of the paying customers would prefer to see a high figure, so rather like a fortune teller, they tell the customer what they want to hear.

If there were three rolling roads locally, two of which produced exaggerated figures, and one which was realistic, how long would would the one producing real figures last? To get a comparison between cars, something like the Santa Pod quarter mile is probably a better bet.

[12TS]

335d said:

The problem I see with rolling road figures is that these tend to be small businesses where 99% of the paying customers would prefer to see a high figure, so rather like a fortune teller, they tell the customer what they want to hear.

If there were three rolling roads locally, two of which produced exaggerated figures, and one which was realistic, how long would would the one producing real figures last? To get a comparison between cars, something like the Santa Pod quarter mile is probably a better bet.

Agreed, or a before and after mod on the same day rolling road on the same day.

[aeropilot]

335d said:

Wills2 said:

People are also using corrected dyno figures on engines that self correct, there was a good article in a major german magazine autobild IIRC that showed when you didn't correct the figures on a modern turbo car the outputs were in line with the manufacturers figures.

The problem I see with rolling road figures is that these tend to be small businesses where 99% of the paying customers would prefer to see a high figure, so rather like a fortune teller, they tell the customer what they want to hear.

If there were three rolling roads locally, two of which produced exaggerated figures, and one which was realistic, how long would would the one producing real figures last?

In my experience, the accurate one would be the one that stays in business....over the past 30+ years I don't know many people that want inflated & inaccurate figures - if so we'd see a lot more Dynojet RR's over here if that was the case.

[SelocMole]

Edited by SelocMole on Saturday 11th June 22:36

[SelocMole]

Does anyone want a 'standard' exhaust for a 340i? It has done the grand total of approx 6 miles. Open to offers!!

[12TS]

Snap! Same colour, wheels, debadged. I wanted to delete the m-sport badge as well, but the salesmen couldn't see how to. I found it later. Hey ho.

[335d]

aeropilot said:

In my experience, the accurate one would be the one that stays in business....over the past 30+ years I don't know many people that want inflated & inaccurate figures - if so we'd see a lot more Dynojet RR's over here if that was the case.

The majority of those using a RR are looking for a number to boast about, in my experience of forums. On the Bimmerpost forums there have been some pretty unlikely figures, normally from those who have a chip on their shoulder about their car no longer being the quickest once a new model is launched. The average quoted RR figure I have seen on forums is about 10-15% above the official figure, and I have my doubts.

My only personal experience of a RR, produced a figure that was about 10% too high in my view, but very much as I had expected.

[SelocMole]

Well after a couple of hundred miles, I am a very happy camper!!

The car is lovely and the bark from the exhaust in sport with a LOUD cacophony of pops and bangs on the overrun is hilariously addictive.

Super-smooth engine and really great auto switching, but in truth I've been using sport and manual selections more than the eco mode... Love the way the car holds on to revs in sports auto mode. It is a great halfway house before going manual.

[interstellar]

I haven't used the Eco mode once and have now done 6000 miles.

[12TS]

Are you noticing the pinking / injector noise I'm having on mine?

[aeropilot]

12TS said:

Are you noticing the pinking / injector noise I'm having on mine?

It's normal. The previous N55 was the same.

[12TS]

I had a 135 before the 340 - I don't ever remember hearing that noise.

[SelocMole]

No, I've not heard any pinking noises... but then again, the exhaust can be loud and I might be missing it.

Certainly nothing / no noises that are making me think that something isn't right.

[Nick_C]

Finally picked mine up today, will have to have a listen for the noise!

Nick

[12TS]

It happens under moderate to heavy throttle loads.

The car seems to coast well, it doesn't loose much speed. Just an observation

Edited by 12TS on Friday 17th June 21:35

[SelocMole]

Getting very addicted to the engine pops and bangs.

Will have to go out at the weekend with the Go-Pro and capture a bit of dashing through tunnels and the thunder on the overrun.

https://youtu.be/tEaH_iS7uu4

[Wills2]

JNW1 said:

Wills2 said:

People are also using corrected dyno figures on engines that self correct, there was a good article in a major german magazine autobild IIRC that showed when you didn't correct the figures on a modern turbo car the outputs were in line with the manufacturers figures.

I don't pretend to be anything approaching an expert in this but if an engine is self correcting on a rolling road that's presumably to allow for the fact that the air flow isn't the same as you'd get in normal road conditions (i.e. instead of the car travelling at 150mph it's sat stationery and relying on fans to provide the cooling instead?). In my simple mind that would tend to result in a lower bhp figure on a dyno compared to what you'd get on the road but if dyno users are then trying to allow for that by correcting their figures it has the potential to become a real bugger's muddle! However, if a car goes in for a remap - and has before and after runs done in the same conditions - presumably the difference between the two does at least give a reasonably accurate representation of what the remap's added?

Yes dynos are great for giving you the delta before and after tuning, the rest has too many variables.

[S3_Graham]

How are you guys finding the MPG? I have a 140 arriving soon and though I obviously didn't buy it to drive in ECO everywhere, would be good to hear some real world experience.