Last week, I was invited to a workshop in Sunway area in KL to tune some cars. Joshua from Millennium Motorsports, who incidentally is also one of my top re-seller for Hondata products arranged for the session.
Joshua who also sells a lot of Microtech products recently just completed his engine built for his race car, a CRX running a huge turbo.
This car made over 1,000 wheel HP on his conservative Dyno Dynamics dynamometer. It has a Honda 4 cylinder H22A motor in there, and to achieve those power numbers are awe-inspiring, to say the least. I was not there to witness the HP run, but I am sure it was done in Joshua’s typical non-dramatic fashion with just plenty of booooostt!!!
So there I was, on a Saturday afternoon and started hooking up the KPro and ECU into the car. Tested the ECU. Made sure I could load maps and make alterations. Confirmed the datalogging works. Wired up a couple of switches for some additional nice features. OK, everything was set, and the car was good to go on the dyno for its tune!
Once on the dyno, we did a base run on the stock ECU when the engine was still cool and not hot from many runs on the dyno. Normally, this would give one of the best horsepower readings assuming the stock ECU had the perfect set of parameters in there then. We normally do that to show the difference in HP we could gain before and after a ECU tune. In the case of the DC5s, we knew for sure the Hondata will make a big difference in power everywhere.
After the base run, it was time to start tuning. A quick switch of ECU from the stock to the KPro and I was sitting pretty with my laptop in the passenger seat with aplomb and going to start tuning the car just like how I did with the other 200 K series engines tunes I have done since 2004.
OK, so we did the first pull…. Hmmm, VTEC would not engage. Took a close look at the datalogs and judging from the logs, it seemed to work. OK, let me try again, maybe the filter was restrictive and we cannot hear the VTEC well since it was set rather low. Run 2; still no luck…
After this, I started to go through the wiring on the car to ensure that everything was correct, and while I was at it, might as well just remove the A’Pexi AFC Neo which was wired into the stock harness. The owner did not want it anymore and so, to eliminate any other causes that might result in a VTEC malfunction, we just removed it.
Now, with the AFC removed, and the wires nicely wrapped back together, it was time to give it another shot. But alas, we were greeted with the same result, still no VTEC!!
After this, we practically tried every trick in the book. Went out to my friend’s car to remove his ECU to test, in case it was a exceptional case where the VTEC driver within the ECU was shot. I have not heard of this happening before with a K Series ECU, but well… there could always be a first. After 30 mins, we got back and tested it out again, but nope, still no luck.
Some other tricks employed were, adjusting TPS settings in the software, shifting VTEC crossover points back and forth and occasionally in part throttle positions while we load the dyno, we are able to get VTEC. OK, at least some conclusions.
1. We can deduce that the ECU works fine.
2. We can also safely say that the hardware on the car was good, as VTEC works on the stock ECU.
3. Wiring is definitely top-notch, all connections were tested and continuous where needed.
4. All sensors related to the fuel injection system reads well, uniformly and correctly.
5. And most importantly, we were hungry.
1 hour later, and after a fulfilling dinner which had the wildest ideas about tuning (and possible solutions to the problems) strewn all over, and back and forth. We went back to the dyno, and to the car which had just got a full tank of gas.
Somehow, suddenly I had a voice that crept up to me and reminded me that I have updated the software about a week ago and had not had a chance to try it on any cars. This definitely was not a problem with the car, could it be within the tuning application?? I never had any problems with new software releases from Hondata. In addition, why would the bug be such a simple one as to be unable to engage VTEC??? VTEC is what Hondas are about, and in that same light, what Hondata is about!
I quickly booted up my laptop again and had a look into the application (not the KManager program) and found something. A quick tweak to the source code was effected and then, reloaded the base map into the car. It all took me about 5 minutes. Started up the car, waited for the cam angles to start working, and did a new run on the dyno. EVERYTHING WORKS!! IT WAS MAGICAL!! After going through the whole agony of troubleshooting for the past couple of hours, the VTEC crossover pitch was definitely music to my ears!!
Let me share a dyno chart of this very car, before and after the tune.
As to the expressions on the owner’s face after he got back from having a crack at his new found power… I shall leave that to your imagination.
