Possible DV Leak? Not meeting Load/Boost/MAF Targets

ByeByeVTEC · 12-12-2023, 09:34 AM

Hello All!

Fairly new to the BMW / MHD world but have quite a lot of experience tuning other platforms using the COBB AP.

I recently got an MHD for my 2012 135i (DCT) and have been experimenting with the OTS tunes while I figure out self-tuning (amazing to find public XDF's for TunerPro, love this community!). The car has 125,500 kms on it and is essentially FBO (VRSF catted DP, M-sport muffler, charge pipe, ETS 7" intercooler).

Since the car is new to me I wanted to start with milder tunes and see how she does. So far I am loving the MHD but while looking @ logs it's clear I am not reaching boost or load targets. I'm running the MHD V1.84 maps for N55e, started with Stage1 93 and now on Stage2 91. My WGDC isn't too high (unless the WG is fully open past 60% and anymore has not effect), AFR are good (seems a bit lean but I guess that's good), just a touch of knock I'm not too worried about..... Seems like it's running well aside from the difference between targets and actual. Would love the opinion of someone who has seen more N55 logs than I do.

I remember back in the day tuning MazdaSpeeds it was common to have diverter valve leakage causing boost recirculation and lowering loads.... Is that common on these N55s as well? Or is it normal for there to be an offset between Load Req and Load Actual on these logs? The car is also making sub 300whp according to V-Dyno w/ smoothing @ 3 and Dynojet corrections (seems low).

Here's a 3rd gear pull from earlier today where you can see the issue. It is not the warmest today but I don't see signs of wheelspin and I had DCT fully off.

https://datazap.me/u/abuseyvr/first-...-44&zoom=36-80

12-12-2023, 09:34 AM	#1
ByeByeVTEC Enlisted Member 24 Rep 43 Posts Drives: 2012 135i Join Date: May 2023 Location: Vancouver, BC iTrader: (0)	Possible DV Leak? Not meeting Load/Boost/MAF Targets Hello All! Fairly new to the BMW / MHD world but have quite a lot of experience tuning other platforms using the COBB AP. I recently got an MHD for my 2012 135i (DCT) and have been experimenting with the OTS tunes while I figure out self-tuning (amazing to find public XDF's for TunerPro, love this community!). The car has 125,500 kms on it and is essentially FBO (VRSF catted DP, M-sport muffler, charge pipe, ETS 7" intercooler). Since the car is new to me I wanted to start with milder tunes and see how she does. So far I am loving the MHD but while looking @ logs it's clear I am not reaching boost or load targets. I'm running the MHD V1.84 maps for N55e, started with Stage1 93 and now on Stage2 91. My WGDC isn't too high (unless the WG is fully open past 60% and anymore has not effect), AFR are good (seems a bit lean but I guess that's good), just a touch of knock I'm not too worried about..... Seems like it's running well aside from the difference between targets and actual. Would love the opinion of someone who has seen more N55 logs than I do. I remember back in the day tuning MazdaSpeeds it was common to have diverter valve leakage causing boost recirculation and lowering loads.... Is that common on these N55s as well? Or is it normal for there to be an offset between Load Req and Load Actual on these logs? The car is also making sub 300whp according to V-Dyno w/ smoothing @ 3 and Dynojet corrections (seems low). Here's a 3rd gear pull from earlier today where you can see the issue. It is not the warmest today but I don't see signs of wheelspin and I had DCT fully off. https://datazap.me/u/abuseyvr/first-...-44&zoom=36-80
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