ricey4you

Greetings from the myg37 forum, below is an excessively comprehensive review of my tuning experience with Eugene @ Enthusiast Auto Care in Concord, CA for my G37S 6MT, and before you ask, there is no TLDR version. Skip straight to the conclusion and you’ll end up missing all of what made my tuning experience with Eugene so great; so i encourage everyone to take some time and read through the whole thing.

Happy Reading!

Backstory w/ Eugene & Enthusiast Auto Care

I started out first slapping on the usual intake and exhaust on my G37 Sedan 6MT. But it was when I attempted to install aftermarket cats and encountered the infamous demon bolts that I met Eugene at Enthusiast Auto Care in Concord, CA. Eugene is a full time computer scientist who also happens to run an accredited ASE certified auto shop attached directly to his house. Upon meeting, Eugene was quick to point out that the faces of the aftermarket cat flanges lacked a protrusion that would prevent potential leaks,. Upon installation, we did indeed find leaks from both cats. I then had several other shops try and fix the leak, but also to no avail. He was also quick to criticize my installation of K&N hot air intakes, and that they were pulling the car down. He was also right, because the moment I replaced them with a Takeda CAI, the car felt much better through all RPM’s. Since then, Eugene has been my go to for all my G37 needs as that’s the platform he specializes in, and it truly does show, with over 170 yelp reviews that are exclusively 5 stars. But this isn’t a review about how great of a mechanic he is; you can read all about that on yelp yourself.*

Just over a year ago, I learned Eugene was also a licensed Ecutek master tuner. I being, previously dyno tuned with Uprev at a different shop, didn’t really see a need to retune since I had not added any mods since my previous tune. And I didn’t quite understand how you could possibly tune without a dyno/why anyone would pay for Ecutek over Uprev.*

Eugene convinced me to switch to ecutek for a reasonable price, assuring me the differences would be night and day based on what he saw after gathering some logs from my uprev dyno tune. I eventually relented in accepting the switch, due to the fact that Eugene has been right about everything thus far despite my skepticism.

My Previous Tune

A little background about my old tune: I was dyno tuned on uprev by a different shop, and wasn’t quite satisfied with the end results of that. The car had perhaps a slight increase in top end, but in exchange, my bottom end was completely useless below 2.5k rpm. After 2.5k, the car would pull about as hard as stock till 4.5-5k. At 5k and beyond the car felt like it had a little bit more power at the top end. The end dyno sheet indicated *294 whp before and 304 whp after. At the time I was satisfied, because I simply thought that numbers don’t lie, and thus far I just assumed that tuning meant you had to sacrifice drivability, to gain that extra bit of power at the top end.*

In the days that followed, I quickly discovered that, commuting through traffic was miserable. Throttle response was sluggish, partially due to the heat soak of K&N short rams, but mostly due to the shitty tune. But I just convinced myself that’s how life would be from now on, in exchange for a top end gain of 10 whp. Lol. The worst part of it all was I had no idea, what the tuner had done to my car, and he refused to share any of the steps he had taken to tune, claiming that it was proprietary and that all my questions were distracting him.

Tuning with Eugene

Then of course came Eugene. His method of datalog based tuning would account for real world driving scenarios, everything from, daily commuting in traffic, passing on the freeway, and of course pedal-to-the-metal redline when hooning around. *He also insisted there was so much more that could be done with ecutek over uprev, not only due to the greater number of tunable parameters, but also due to the custom programming language that Ecutek layers on top for the purpose of building custom functions. And most awesome of all, Ecutek’s OBD adapter contains a bluetooth transmitter that linked directly to my smartphone through an app, and allowed me to monitor and log all of my car’s stats (oil temp, fuel trims, ignition timing, air fuel ratio, the list goes on and on).

After making the switch, Eugene reverted my car’s ecu to factory stock, eliminating any evidence of the last uprev tune; (much to my dismay, thinking all that dyno time was wasted). But Eugene, assured me this was the best way to start to get the most accurate log data from the ecu to see what the car was doing in its natural state with whatever modifications it had added. He then had me log all my normal driving for the next few weeks till there was about 50 – 100 MB of log data, which I uploaded to a cloud folder for him to access. He reviewed the log data and was able to see what scaling needed to be done to my MAFs (Mass Air Flow Sensors) due to my cold air intakes. Eugene explained that before he could build my timing map, he would have to ensure my MAFs were scaled as accurately as possible. He explained that the commanded ignition timing is computed by reading a table of RPM vs Load, and airflow reported by the MAF sensors is a major contributor in determining the engines load.*

Now what sets Eugene apart is that he doesn’t build tunes manually. As a computer scientist, he developed his own suite of algorithms to process log files and generate corresponding tune adjustments. By doing this, he is able to produce a more precise tune because the large amounts of data that he feeds to these algorithms spans a broad range of situations I had encountered during my logged driving with respect to things like load, rpm, throttle position, etc. This computer algorithms generated maps, corrections, etc., end up more accurate than any human would ever be able to do manually by log review, as every single logged data point is taken into account for calculations, not just what the human eye can see on the 3D chart.

After the corrections were made and flashed onto my vehicle, he had me continue logging to see how the car accepted the tune and how much closer the fuel trims were, in order to prepare a new flash with updated scaling. This cycle of logging/correcting/flashing continued a number of times until the log data indicated a minimum error in computing engine load, evidenced primarily the short term and long term fuel trims.

Eugene was now able to work on ignition timing in order to maximize power. He accomplished this once again by having me log a large amount of data and using one of his algorithms to create a timing map. Once again after a few rounds of logging/flashing, he was able to zero in on the perfect timing map. Compared to stock, the new ignition timing map made my car much more responsive to input at all RPM’s (especially down low where there used to be a delay). Additionally the car made a lot more torque in the mid range, and absolutely soared at the top end.*

Along the way, Eugene was also able to create a custom function that allows me to select a target afr (air/fuel ratio) for WOT (wide open throttle) and a custom map that allowed me to select between 12 different throttle settings.*

Conclusion

In the end, after nearly 1 GB of data and over 20 revisions, I was extremely satisfied with how the car came out, and am a firm believer that log based tuning is just as good if not better than dyno tuning. Not only did the car feel amazingly better in nearly every RPM, but I felt I learned a lot (possibly too much) about tuning myself. Eugene, made sure to involve me and explained to me every change he was making to the vehicle. He had absolutely nothing to hide (except maybe his proprietary algorithms), and he made it a point to make sure I understood everything there was to know.*

I am so satisfied that I am very reluctant to ever change to any other car that isn’t a G or a Z, knowing that I won’t have someone like Eugene to take care of both my car mechanically and for all my tuning needs.*

Next up? E85. Will update further when I decide to finally go through with this...