Performance boost after driveshaft replacement?

[FIN_Nole]

Maybe i just missed not having my car for a day, but I swear the car feels faster and sounds better after having the driveshaft recall service performed today. Nothing else was touched (to my knowledge). MDM also seemed a little less intrusive. Is any of this possible?

I know feel and reality can be totally separate things... Hopefully someone can enlighten me here (and yes I searched, including the 41 page driveshaft recall thread)

Could it be the combination of my MPE with the boost increase BMW is using to offset filters being added with the driveshaft replacement?

My car is a 2017 F80 ZCP Dinan S3 w/ M Performance exhaust

[GearRex]

Originally Posted by FIN_Nole

Maybe i just missed not having my car for a day, but I swear the car feels faster and sounds better after having the driveshaft recall service performed today. Nothing else was touched (to my knowledge). MDM also seemed a little less intrusive. Is any of this possible?

I know feel and reality can be totally separate things... Hopefully someone can enlighten me here (and yes I searched, including the 41 page driveshaft recall thread)

Could it be the combination of my MPE with the boost increase BMW is using to offset filters being added with the driveshaft replacement?

My car is a 2017 F80 ZCP Dinan S3 w/ M Performance exhaust

Placebo effect.

Similarly, my car feels awesome after an oil change. Maybe a combination of that and cooler weather...

I chuck it to "happy to be back on my car" thing.

This is why they give you 328i loaners.

[FIN_Nole]

Yeah, that would make the most sense. Although I didn't take a loaner or even drive between the time i dropped it off yesterday and when I got it today but the feeling of getting it back may have been enough.

If BMW is upping boost to offset an additional filter (and I don't even know if this is fact since my SA had no knowledge of the service itself), would exhaust type or other performance options be factored into the amount of boost needed to offset the restrictions caused by the new filter? My point being that if BMW is simply using a fixed value without accounting for all other factors, outputs would vary right?

[G4BR13L]

Did you have a CFRP driveshaft that got replaced with a steel one? As far as I know no particulate filter is installed at the time of this writing. The driveshaft recall is not related to BMW switching to steel driveshafts it had to do with the quality issues with the flange of some of the CFRP driveshafts build during in a specific period.

Switching to steel means that the driveshaft will weigh more and theoretically this results to less torque transferred to the rear wheels through the rear differential.

I don't know where you heard or read that BMW increased or will increase the turbo boost pressure for compensating the lost torque, I seriously doubt this. Yes BMW could increase turbo boost pressure by adjusting the operating point mappings used by DDE control unit (which controls the electrical wastegate actuators). By the way in Sport and Sport+ they wastegate valves are already fully closed under partial load.

There are only two logical explanations for switching from CFRP to steel driveshafts:

Cost
The first reason but not the main reason is cost reduction or at least they had to choose between the cheapest solution for the second reason. Although BMW could have redesigned the CFRP driveshafts to make room for a particulate filter do not underestimate the total cost of such a redesign. I still hope that the G8x will come with a redesigned CFRP driveshaft and if they do it is also possible that these CFRP driveshafts cannot be installed on the F8x.

Euro 6d
The second and the most important reason are the Euro 6d emission standards. As of 1st September 2019 Euro 6d-TEMP will become mandatory and this means that (new) M3/M4 cars sold will need a petrol particulate filter (PPF). Taking into account that the G80 will be released somewhere in 2020 and the G82 most probably somewhere in 2021 you realise that BMW had no choice here. They also had to take into account possible delays of the G8x which means that the current generation F8x would be sold for a longer period than anticipated. And because the new steel driveshafts were already available they decided to keep using the CFRP driveshafts until they were end of stock.

[Harpinc]

You guys didn't know that BMW will turn it up after you get a new DS?? LOL

[Sublimeside]

Originally Posted by FIN_Nole

Maybe i just missed not having my car for a day, but I swear the car feels faster and sounds better after having the driveshaft recall service performed today. Nothing else was touched (to my knowledge). MDM also seemed a little less intrusive. Is any of this possible?

I know feel and reality can be totally separate things... Hopefully someone can enlighten me here (and yes I searched, including the 41 page driveshaft recall thread)

Could it be the combination of my MPE with the boost increase BMW is using to offset filters being added with the driveshaft replacement?

My car is a 2017 F80 ZCP Dinan S3 w/ M Performance exhaust

Did they replace yours with a steel DS? My SR says when I take mine in on May 3rd, it will be replaced with steel. I also have a 2017 F80 ZCP built in July 2016.