[jakub.m]

Hello,
Car: m340i xdrive 2022 berline
30.000km
Brand new ps4s tyres
Launch control with 0 lose of traction

Next week I will be putting modifications on my car so i bought draggy.
Now I tested some 0-100km/h times (car is stock now)
Best I could get when alone in the car was 4.51 sec
Best time with a passenger was 4.61 and sometimes even 4.7
I know bmw says its 4.4 sec but every video or forum I see, people are doing 3.9-4.2 sec
And 0.3s-0.5s is a huge difference…
What do u guys think that could be wrong here or do I just have a slower car?
Maybe spark plug can cause this?

Thanks in advance!

[cyam]

Hard to tell. Mine is a 2020 M340ix stock I always got under 4.0, 3.9 sometimes 3.8.

Tuned - downpipe and a 91 fuel tune and I now get consistent 3.4.

Are you launching properly? Set to sport+, set to "Traction", then push brake pedal HARD all the way to the floor, then press Accelerator all the way to the floor. "Launch..." should up on the dash. Hold for a couple of seconds then let foot off brake.

Are you doing all that?

[jakub.m]

Yes im doing all that (launch controll) i even tried holding it longer so its going past 2.5k rpm.

[cyam]

What ambient temp was it?
Is the air filter new/clean?
What fuel are you using?
What boost are you hitting? Does it vary once you reach full boost, like does it drop back a bit during the run?

[jakub.m]

Temp was around 25c sunny i know turbo cars dont like heat but 0,5sec difference ?
Fuel is 98 fuel best i can get in my area i will to get vshell and try than.
Is it possible that one spark plug is not good or something after the blw changed the sparkplugs ? The car felt slower when i got it back but maybe just a feeling…

[cyam]

Originally Posted by jakub.m

Temp was around 25c sunny i know turbo cars dont like heat but 0,5sec difference ?
Fuel is 98 fuel best i can get in my area i will to get vshell and try than.
Is it possible that one spark plug is not good or something after the blw changed the sparkplugs ? The car felt slower when i got it back but maybe just a feeling…

Well maybe it's not a feeling when your times are evidence.

What about boost? Does it stay on full boost the whole run once it reaches full boost, or does it drop at all?

If you just got plugs changed and you felt it different, then maybe something wasn't done right. Not that you can really get that wrong...

[jakub.m]

I did some quarter mile runs . Seems im losing all my time in the launch ? This was my best what do u think? Can it be that slow or is something wrong?

[jakub.m]

Originally Posted by cyam

Well maybe it's not a feeling when your times are evidence.

What about boost? Does it stay on full boost the whole run once it reaches full boost, or does it drop at all?

If you just got plugs changed and you felt it different, then maybe something wasn't done right. Not that you can really get that wrong...

I will monitor the boost next time when I do it.
Do u hold it till u reach full boost ?and than launch ?

[cyam]

Originally Posted by jakub.m

I will monitor the boost next time when I do it.
Do u hold it till u reach full boost ?and than launch ?

No, just hold it for a couple of seconds after you see the launch message.

[cyam]

Originally Posted by jakub.m

I did some quarter mile runs . Seems im losing all my time in the launch ? This was my best what do u think? Can it be that slow or is something wrong?

Your launch may be OK. But those times seem very slow compared to what most of us are seeing.

Can you try on a 0 degree slope? I don't think 1.5 degrees would show you down like 1 sec 0-100.

[jakub.m]

Originally Posted by cyam

Your launch may be OK. But those times seem very slow compared to what most of us are seeing.

Can you try on a 0 degree slope? I don't think 1.5 degrees would show you down like 1 sec 0-100.

Would u go to the dealer with that or are they just gonna igone me and say its just a little slower?…

[cyam]

Dealer won't do a thing, it'd likely be a negative thing to do.

Maybe check to see if any dtc codes are present. Try logging some data with a monitoring sw, even bimmerlink may provide some data.

[komoornik]

Yeah, the time is not great. But not terrible

For reference, I was able to do a similar 4.5s 0-100 on my much heavier stock M440i xDrive cabrio - also using Dragy to measure.

[jakub.m]

Originally Posted by komoornik

Yeah, the time is not great. But not terrible

For reference, I was able to do a similar 4.5s 0-100 on my much heavier stock M440i xDrive cabrio - also using Dragy to measure.

I idk if i have the” world slowest m340i” or something is wrong.
I want to tune the car but now im scared to void warranty

[cyam]

Originally Posted by jakub.m

I idk if i have the” world slowest m340i” or something is wrong.
I want to tune the car but now im scared to void warranty

All I can say, is from the information presented, something is not right. It should be faster. So while the acceleration is not an issue per se, compared to others its slow, which is just a sign something isn't right. That'd be my concern. I'd want to know what is not right.

[jakub.m]

Originally Posted by cyam

All I can say, is from the information presented, something is not right. It should be faster. So while the acceleration is not an issue per se, compared to others its slow, which is just a sign something isn't right. That'd be my concern. I'd want to know what is not right.

I did some more runs.
I did look at boost and it doesnt drop
My new pb with 1/4 98 premium fuel
Ac off
Holded boost for 2 sec after launch controll popped on my screen .

[huzidada]

Whats your tyre pressures like?

[jakub.m]

Originally Posted by huzidada

Whats your tyre pressures like?

2.6