[zach415]

Hello fellow friendly forum frequenters, I am hoping some people here can help provide some insight into the data logs I have been recording off my car. At the moment I believe the car is pulling timing for some reason that I am having trouble determining, as well as potentially hitting the ceiling of the HPFP capabilities.

Car is a 2019 X3 M40i.

I will link the logs below, and provide context for the situation.


Spark Notes:

The car had a Evolution Racewerks catless DP, Brand new 0.022" gapped 92401 NGK plugs, and the Stage 2 91ACN (AGG) OTS tune from BM3 (protuningfreaks) installed, and is now running slower Dragy times than it was in a full stock configuration. Logs are linked below.


Full Context:

Car was completely stock before being taken to the shop for removal of stock DP, install of Evolution Racewerks catless DP, and flash of Stage 2 91ACN (AGG) OTS tune from BM3 (protuningfreaks), at this time the stock plugs were left in. Installs went smooth with the exception of the Tech calling out that the TCU did not flash a tune because it was not available for the car (I was in the shop with them during the flashing).

I took the car back and on the drive home it had noticeably more kick to it when applying moderate throttle. However, from the first WOT pull, I could feel the car not giving all it had, the butt dyno simply felt as if it was pulling power or something was not as smooth as it could/should feel. Dragy testing confirmed that the car had dropped from 4.4s 0-60 to around 4.6-4.7s 0-60. Immediate reactions were that we just goofed in not ordering and gapping new spark plugs when going to the stage 2 tune, so that is what was done.

After installing the newly gapped plugs this week (Stock gapped to 0.030", now on new OEM plugs gapped to 0.022"), the car has gained some speed and is now back to the stock numbers of 4.4s 0-60. Obviously that is far underperforming what I would expect after going to a catless DP and a Stage 2 tune. The data logs seem to show the same amount of total timing correction both before and after swapping to the new gapped plugs. Logs are linked below.


Data Logs:

0-60 Run:https://www.bootmod3.net/log?id=630f...90c60183da82bd

3rd-4th Gear Pull:https://www.bootmod3.net/log?id=630e...0b4355835d66de

Any insight from the community is greatly appreciated, thank you in advance for anyone taking a look at the logs!

[dinan5m3]

Definitive Gen1 B58 data log review thread

https://f30.bimmerpost.com/forums/sh....php?t=1648722

There are crazy # of gen1 b58 tune experts in that forum.

That is a good starting place.

[suby01]

I am no pro at this.
My 1st question is why did you change out your plugs? You are not running past 20psi and are using low octane to ever need anything changed in your ignition.

I checked your logs from what I understand. It shows you have no knock which is great but you are overboosting for some reason. This is giving you higher PSI than what you are supposed to have by the OTS map and its confusing your car and causing it to run slower.

Others will have a lot more knowledge in this but that should be the basis.

[zach415]

Originally Posted by dinan5m3

Definitive Gen1 B58 data log review thread

https://f30.bimmerpost.com/forums/sh....php?t=1648722

There are crazy # of gen1 b58 tune experts in that forum.

That is a good starting place.

Thanks for this call out! Great info in there

[zach415]

Originally Posted by suby01

I am no pro at this.
My 1st question is why did you change out your plugs? You are not running past 20psi and are using low octane to ever need anything changed in your ignition.

I checked your logs from what I understand. It shows you have no knock which is great but you are overboosting for some reason. This is giving you higher PSI than what you are supposed to have by the OTS map and its confusing your car and causing it to run slower.

Others will have a lot more knowledge in this but that should be the basis.

Thanks for taking a look at the logs. As far as the plugs, this gapping was suggested by the folks who worked on the car, as well as other BMW tuning shops I reached out too. I also plan to run flex fuel in the future, so this gapping will allow for that as well.

Regarding the overboost comment, what would you expect the OTS tune to target? The thread linked above lists this map as having a 19 PSI starting point, however that thread is not only specific to X3's, but I would assume the B58 maps would be fairly equivalent across the board.

[suby01]

You are correct that the boost target should be around 19PSI for your fuel and OTS. And thats there it is its right a bit over 18 PSI as a target. But you hit 21 PSI at as low as 4K RPM. Thats where the issue youre exceeding the target and thats not always good.
Having 21 PSI Vs 18 or 19 PSI should be more power of course. But not when your targeting lower and you shoot past that.
Thats your overboost.