As promised guys here is the dyno results and write up for the Okada coils on my 2.0tfsi TT on stage 2 revo software.
Current engine set-up: Blueflame 3" TBE with racing cat, ITG enclosed intake, Upgraded DV, Neuspeed Power pulley, Neuspeed intercooler to throttle body pipe, NGK Iridium BKR7EIX plugs, Revo Stage 2 and of course the OEM and Plasma direct coils.
So what I wanted this test to be about is to see what the difference is between the OEM coils and the Plasma direct coils (hereby will be called PD coils). I took the opportunity to test other potential mapping settings and altered the AFR mixture and also timing while logging the runs but kept the boost setting the same throughout.
In total I did about 25-26 runs on the dyno and played around with the settings a fair amount. The temperature was reading 29 degrees in the dyno room as managed to pick a nice hot day to do the runs on! Heatsoak was a little bit of an issue so the results are taken from the same point on a set of runs to keep the best accuracy. It seemed generally the case that the first run was giving slightly better results and started to trail off on the 3rd and 4th consecutive run. Power figures in general are going to be a good 10bhp less than a good cool day as the temperature for a standard intercooler was a little stressing.
So away with some of the runs. To start off with we tested the Okada coils as a baseline on settings: Boost 6, Timing 4, AFR 8. Timing pull was coming up at about 2.3 and 3 on some cylinders which seemed it was pretty well set-up timing wise. The AFR looked healthy and the turbo giving a good 1.35-1.4 Bar. Peak BHP was 259.1BHP.
After a set of runs and logging the first thing adjusted was the AFR mixture to a level which Jim at JKM believed would give enough of a result to see on the dyno. The settings we went with was B6 T4 AFR4. From looking at the runs it was quite clear this was far too rich and seemed to only give a better graph power curve at the very latter part of the RPM range, the first 2/3rd's of the rpm range was quite down. Peak BHP was measured at 251.7BHP
The next run was changing the AFR back to 8 as this seemed to look best on the logging and on the dyno graph too. The timing was altered to retard as it would be a little dangerous to advance timing looking at the knock logs. This test is to see how the PD coils work with retarding the ignition, settings were set to B6 T2 AFR8. The peak power came out at 252.1BHP, it seemed a similar story with going richer on the AFR and that the early part of the power curve was down.
After these runs the settings were set back to B6 T4 AFR8 and run again to see how the temperature had changed and to create another baseline before immediately changing the coils. The peak power came back to 258.7BHP and seemed much stronger than any other settings. It seems the settings previously set-up on the car work the best and the PD coils didn't respond to changing the AFR or retarding the ignition. Not a huge surprise but shows how the power can affected by changing the settings.
Graph of the 258.7BHP run-
Next is on with the OEM coils and keeping the same map settings (B6 T4 AFR8). The peak power came out with 256.5BHP which was the best curve by some margin, the other 5-6 runs came out with a similar peak but not as high power on the curve throughout.
The next graph is comparing the Okada PD and OEM coils on the same graph. Red is PD and Blue OEM.
I decided to take the next best OEM coils run compared to a run on the Okada PD at the same point. Red is PD and Blue OEM.
The Max BHP listed on the top of the graph is not the overall BHP but the BHP of the last run which was the OEM coils in both graphs. It's hard to take a complete definitive result on the early part of the RPM range and the power and performance of what both coils give. You can see on one graph the OEM has a stronger curve up to around 5,000 RPM but on the other graph the PD coils seems to be stronger over the entire curve.
It would seem that there is a common theme in the PD coils being able to keep a higher power figure over the last 1,000 RPM whereas the OEM seem to struggle a little more.
ConclusionIt would seem that both the OEM and PD coils react in a similar way when it comes to variations on mapping and have logs that look and read almost the same. I am undecided on whether the PD coil has a definitive gain over the majority of the RPM range, unfortunately it's not clear which one is better as different runs show they out do each other. Apart from 1 run on the OEM the Okada coil seemed to be stronger over the entire curve as shown in the 3rd graph. However it does seem the PD coil always had one over the OEM coil when it came down to the end of the RPM range and at times seems to hold another 10BHP over the OEM coil.
I would like to think I did this test as fair as possible. The results were taken within 20 minutes of each other (changing the coils), so the ambient temps were the same. The graphs were taken of the runs at the same point in each "session". The car was putting more power out first thing but this was not a fair test as the OEM coils were put on an hour and a half later so I took the last run before the OEM coils.
Do the PD coils give a gain? Answer would seem yes about 2.5 BHP more peak, they seem to hold the power for longer in the latter RPM range. And at times out do the OEM over the entire RPM range.
Was my 2.0tfsi the best test for these? Maybe. My 2.0tfsi was running a standard intercooler and fuel pump which meant it was not running near it's potential. I will go an get the next couple hardware mods sorted out with a stage 2+ remap and will do another back to back with the coils to see whether this would justify getting the PD coils more on a K03 turbo'd 2.0tfsi.
So what's next? In all honesty I would love to try these out on a higher powered engine as the demand for a higher spark is needed. The standard 2.0tfsi coils seem to do a good job and I think they start to get stressed on a K04 rather than a K03.
I would like to think they are a justifiable cost and if they outlast the OEM by 3-4 times then really they would be. Power wise they have given gains and possible more on a higher state of tune. MPG seems to be around 39 so maybe a 2MPG gain, I haven't done enough driving to say for certain and a 2MPG over only 400 miles of running is not clear enough to say for certain.
Hope you enjoyed the read
Thought I would add a picture too.
