[HighlandPete]

Originally Posted by ridetime

That could be but in the US the definitive standard is the EPA figure on the window sticker. All manufactures want those numbers to be as high as possible. If there was improvement in the mileage numbers you can bet BMW would make sure the correct numbers were reflected on the sticker. In the case of the 2022 48v X3 M40i they did not improve compared to the 2021 model.

To be fair, European fleet 'average' CO2 levels are what dictate the installed features. If BMW are knocking off about 8g/km per vehicle over here with mild hybrid add-ons, that is driving the technology.

[ridetime]

Originally Posted by HighlandPete

To be fair, European fleet 'average' CO2 levels are what dictate the installed features. If BMW are knocking off about 8g/km per vehicle over here with mild hybrid add-ons, that is driving the technology.

Agreed. It is all about emissions.

[Speedguy22]

2022 X3M40i here, US, with 48V MH system.

The auto-start stop cannot be disabled, as far as I can tell, at least from regular, non-coding mechanisms. That said, the start/stop is really seamless, and I hardly notice it. I've certainly saved gas on my first 1200 miles. As for extra speed, it does help with that first 0-15 MPH range, esp when not on a full kick down (which I've only done once so far).

I'd say that if there were a way to completely turn it off, I would use that from time to time, but putting it into Sport has the same effect in 95% of cases.

[duegatti]

I had a similar experience in a test drive. I didn't notice the start/stop.

[1speedbike]

Originally Posted by Speedguy22

2022 X3M40i here, US, with 48V MH system.

The auto-start stop cannot be disabled, as far as I can tell, at least from regular, non-coding mechanisms. That said, the start/stop is really seamless, and I hardly notice it. I've certainly saved gas on my first 1200 miles. As for extra speed, it does help with that first 0-15 MPH range, esp when not on a full kick down (which I've only done once so far).

I'd say that if there were a way to completely turn it off, I would use that from time to time, but putting it into Sport has the same effect in 95% of cases.

You can also put it into "sport individual" and the start/stop is turned off, and then turn all the individual settings to "comfort"

[efisher13]

Originally Posted by 1speedbike

You can also put it into "sport individual" and the start/stop is turned off, and then turn all the individual settings to "comfort"

Exactly and then code it to start in sport individual. However, the short time I had it enabled you really didn't notice the start/stop. The 48v certainly helps with the turbo lag coming from a 19.

[ridetime]

Originally Posted by efisher13

Exactly and then code it to start in sport individual. However, the short time I had it enabled you really didn't notice the start/stop. The 48v certainly helps with the turbo lag coming from a 19.

Any chance the decreased turbo lag could be the updated 20+ B58 compared to your 19?

[Jen4BMW]

I don’t know about improved gas mileage but I can attest to noticeably smoother shut downs where a jerky shudder or two on shut down was commonplace. I found ASS to be one of the weakest calibrated systems on my 2019 X3 30i. I never completely adjusted to it. Countless times the car miss judged the stop and shut off too soon. On this LCI, start and go is now buttery smooth with absolutely no lag. Start and go is just a super quick pop off the line. I was a skeptic but I am starting to think this new 48V system is the real deal.

[RichC]

The auto start stop is definitely more seamless than other cars I have without the mild hybrid. We are only on out second tank of gas and our average MPG is 25.1 with 91 octane fuel. Our driving is 60% city and 40% highway, which I think is pretty good. I'm glad we have it.

[efisher13]

Originally Posted by ridetime

Any chance the decreased turbo lag could be the updated 20+ B58 compared to your 19?

It’s possible but highly unlikely. The 19 was tuned so it actually had more horses then the stock 22

[newtoncd8]

Originally Posted by efisher13

It’s possible but highly unlikely. The 19 was tuned so it actually had more horses then the stock 22

Are you talking about stock for both? The 2019 M40i had 355hp and 2022 M40i has 385hp.

[ridetime]

Originally Posted by efisher13

It’s possible but highly unlikely. The 19 was tuned so it actually had more horses then the stock 22

But we are talking about turbo lag. It can have 1000hp and still have turbo lag it has nothing to do with hp.

The 48v setup may have electrical advantages powering all the electronics in a modern car but according to BMW and the EPA it did nothing for acceleration and fuel economy is actually worse.
It may also smooth out the start stop system but it will never be smoother than a 18-21 with start/stop disabled.

[jeebus]

As someone that absolutely hated auto start/stop on every other vehicle I've owned, I have to say it's pretty great in the 22 m40i. Very smooth. The eboost gets the car moving from a stop without any fuss. I can't imagine wanting to code this system off entirely.

Plus in sport mode the start/stop function is disabled so you don't even have to think twice about it.

[RedJon]

It’s for CO2 reduction, there’s no real user benefit imho

[murellus]

Is the 48V system battery have a specified service life? Can't seem to find anything, wondering if this is a nasty cost down the road.

[MasAyinde]

My '20 M40i has an identical "battery charging" graphic to my brother in laws plug in hybrid X5. My manual also states that the battery needs to be charged when i notice that acceleration is poor. I have personally also felt, in certain circumstances, instant power when I touch the gas. I don't mean ICE instant, it's something that I've only felt driving electric cars. I suspect that the mild hybrid tech was implemented in '20 and '21 model years, but only really advertised in the 2022 M40i.

[ridetime]

Originally Posted by MasAyinde

My '20 M40i has an identical "battery charging" graphic to my brother in laws plug in hybrid X5. My manual also states that the battery needs to be charged when i notice that acceleration is poor. I have personally also felt, in certain circumstances, instant power when I touch the gas. I don't mean ICE instant, it's something that I've only felt driving electric cars. I suspect that the mild hybrid tech was implemented in '20 and '21 model years, but only really advertised in the 2022 M40i.

[ElCid08]

Like everyone has said…start stop is noticeably better/less intrusive in my 22'. I have lots of seat time in my wife's 21' for comparison. I'm really curious for someone to strap a 22' M40i to a dyno. I want to see actual power numbers. Weight/HP/ claimed performance figures from BMW don't line up. I've owned multiple "muscle cars" and "actual" M cars and my 22 M40i feels like a beast.

[Shaun170]

I’ve noticed a few times in mine that as I’m about to stop behind queuing traffic and I’m approaching very slowly, creeping to a stop, the engine cuts out just before the point of stopping. Don’t know if this is anything to do with the mild hybrid. Never had a stop start engine car actually cut the engine until I was completely stationary before.

[Rik762]

I believe that the engine will cut out around the 9mph mark under the right conditions.

[Cabman]

I noticed that if I am in ECO pro mode that if I am going down hill and not excellerating the engine goes into “ready “ mode.

[jsh139]

Both of the above scenarios are intentional and outlined in BMW’s literature regarding the mild hybrid system.