(Solved) MHD related tuning question

TheFixer

Sergeant
Aug 16, 2020
493
352
0
Tennessee
Ride
2008 535i
I put some BL coils on my car and clicked the option in MHD for them. I feel like the car is running smoother because of them.

My wife says the car isn't running as aggressive as before because she feels the boost isn't hitting as hard.

So today I put the ngk coils back on.... and yeah I noticed the car is much more aggressive with those. However they sometimes cause a misfire under heavy load. That's why I put the BL coils on. Anyway, put the BL coils back on and it definatley isn't as aggressive.

Am I missing any other options that I should be selecting with these coils?
 
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Dumaurier7

Lieutenant
May 19, 2020
560
230
0
The option is only to increase the dwell (charging) to saturate the coils, probably your spark is now too hot causing knock which would make the ECU pull timing, do some logging and compare ignition timing when using both coils, also, you should be using colder plugs if your are running "hotter" coils!
 
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TheFixer

Sergeant
Aug 16, 2020
493
352
0
Tennessee
Ride
2008 535i
The option is only to increase the dwell (charging) to saturate the coils, probably your spark is now too hot causing knock which would make the ECU pull timing, do some logging and compare ignition timing when using both coils, also, you should be using colder plugs if your are running "hotter" coils!
Thank you for the info. Turns out I selected the wrong octane option both times I reflashed with the new coil option. Not sure how I overlooked that...... getting old I guess.