BMW N54 – Cylinder Timing Corrections and Tuning for More Reliable Power
Posted on 12 August 2012
There seems to be a lot of discussion on timing corrections on the N54 and what they mean. Are they bad? Will my engine go kaput if I have some corrections occuring? What happens when my meth isn’t flowing right and corrections happen? Etc etc etc.
If you’ve ever had a chance to datalog a tune on your N54 extensively (and yes, your 100% bone stock N54 with zero modifications or tuning also has a tune, only in that case the OEM one) and done so in situations such as Wide Open Throttle (WOT) as well as cruise and part throttle you’d quickly realize that corrections happen under all of these scenarios irrespective of the driving situation.
In an attempt to answer some of those questions and clear some confusion let’s just concentrate on what BMW themselves did at the factory after countless hours of research and development and in the end flashed your original/stock BMW DME/ECU and gave you warranty bumper to bumper for 50,000 miles of any driving you wish to do (as long as you don’t modify it of course).
In order to get our data we’ll use the Cobb AP unit and datalog a STAGE ZERO map. All the OEM tuning parameters in that map are 100% STOCK as they came from the factory.
Upon looking at the above STAGE ZERO datalog you’ll notice that even the DME programming that came originally from BMW encounters timing corrections. This datalog shows a run under Wide Open Throttle (WOT) where timing corrections happen on cylinders 1, 3 and 5. Boost is stock hitting 7psi tapering to 5psi at above 6k rpm.
In conclusion, timing corrections are part of this platforms elaborate timing control and are not necessarily bad for your engine. No one in their right mind can say that the original BMW programming will make this motor die after a few WOT runs or an all out day at the road course. In addition to that a number of piggyback tuning solutions have run these engines to significantly high power levels without ANY timing remap without any documented engine failures and they encounter timing corrections every pull (only you may not be aware of them as you can’t datalog them but they’re easily spotted if even timing on cylinder 1 is datalogged).
When it comes to tuning for more safe reliable power from these cars/engines we rely on all the information in these datalogs we can get. From our extensive testing on the road and on the dynos we know where a certain car on certain octane in certain conditions and with certain modifications SHOULD be. That is what comprises our BASELINE and we usually use the Off The Shelf (OTS) maps from Cobb as a great tuning starting point. From there we look at datalogs under various driving conditions such as Wide Open Throttle (WOT) and adjust parameters in the map accordingly always ensuring we stay within turbo compressor efficiency maps (i.e. not overstress them by adding more heat vs power) and don’t over-advance the ignition timing for a given octane at the given boost levels.
In the end, striving for zero timing corrections out of your tune you’re leaving potentially A LOT of safe reliable and consistent power on the table and on top of that it may or may not even be possible zero them all out at all times no matter what octane/boost/timing/afr you run. What it comes down to is that this is just another metric we refer to during our tuning process. Pushing reliable power further while always looking for the right balance of all running parameters for your particular engine/car is what it comes down to in the end and timing corrections are only part of that story.
If BMW’s own original tuning is allowed to have some timing corrections, well, we won’t pretend we can do it better than them.
Enjoy your N54s, some timing corrections are A-OK! ;)