Updated: Mar 30
The most significant part of a quality EFI calibration is a vehicle's drivability. This ranges from shift quality, to idle sound, to the overall driving characteristic of the vehicle. Items as simple as shift points can make or break the way a vehicle drives. With a remote tune, the quality of your vehicle's drivability will significantly rely on your ability to communicate with your tuner!
When attempting to tune for drivability improvements, your remote tuner likely won't be able to see the items you're hoping to improve on a datalog, as the data from your ECU will not call out deficiencies directly. The things you are looking to correct are qualitative in nature rather than quantitative. This is where you come in to help!
With this intention in mind, there are some things I'd like to share that could help identify the correct quantitative parameters to change to provide qualitative improvements.
Bookmark Your Logs
It's difficult and un-safe to look at a log's timestamp while driving. It's sometimes useful to bookmark portions of a log that you'd like to review in further detail later. You can even do this by driving the vehicle in specific ways! You can later look for these driving events to find specific points in time on a log.
Examples of ways to Bookmark logs:
- Drive -> Neutral -> Drive
- Blip throttle three times
- Roll into and out of the throttle a few times
- Stop for a specific amount of time afterwards
Create Targeted Logs
Keeping shorter logs that recreate the drivability concern that you're trying to improve can help bring focus to important data you may be overlooking. Try to focus on resolving one or two items at a time when drivability tuning.
When taking the vehicle out on the road to log, find a quiet section of road, start a new log, and try to re-create the condition you're troubleshooting a couple of times sequentially. Immediately after this, stop the log and head back to a comfortable place for review. This keeps logs relevant, and provides a few different instances of a condition to compare and contrast against.
Sometimes when working through the process of fine tuning how a vehicle drives, it helps to make a data sheet to record a list of different but similar driving scenarios so that you can compare them qualitatively. Clearly, you shouldn't be typing while driving. Instead, find a passenger or sound recorder to help you take notes. For this propose, I've had good luck using a GoPro to narrate my drives and announce any adjustments I'd like to make.
A great application for using a data sheet to organize your feedback would be recording desired changes to shift quality. For each shift, keep track of firmness at low, medium, and high load. From this, you'll have the data needed to adjust pressures and shift times to get the shift feel you're looking for.
Low Load: Too soft
Medium Load: A little soft
High Load: Good
Low Load: Good
Medium Load: Good
High Load: Slightly too soft
Low Load: Flare shift
Medium Load: Too Soft
High Load: Good and firm
With this data and a good log, you theoretically could figure out what shift times to target in order to provide good shift quality, as well as make meaningful changes to dial things in.
Your feedback matters!
Having the right qualitative feedback to interpret a datalog is critical to a calibration you'll love. We know that sometimes the right tuner for your car is miles away, and hope these tips help you better convey your needs to them remotely!