OK, finally had my ChipTorque Exede fitted & tuned by Steve Knight yesterday.
Before runs (with Exede fitted but with bypass plug inserted) showed between 160 and 163 kw atw. And very rich AFRs, which we expected.
About 21kw less than my earlier runs back in August 2009. All sorts of possible reasons for this difference, including larger wheels & tyres (245/35 19 v 235/45 18), slightly different weather conditions (but not much), incorrect parameters set by Steve last time (I think this is a strong possibility, note the big difference in SAE J607 correction parameters, from around 2.8 last time to 3.95 this time), and this time I noticed/heard a lot more slip on the rollers.
Steve reckoned that Mitsu motors have good days and bad days, and the day back in August 2009 must have been a good day and yesterday was a bad day!
I reckon the slip was a big factor, when I drove it off the rollers the front wheels were spinning on the concrete floor at 1200 rpm!
The after runs, once Steve had tuned the Exede, showed 168 - 170kw atw. So a reasonable increase in top end power.
I was hoping for an increase in torque in the mid-range, but this didn't happen, instead I got a reasonable increase in the top end, from about 4,000 rpm onwards.
The main change was in the AFRs, now tuned so that it runs between 12.5 and 13.4 instead of the horribly rich 9.6 to 11 that it was running.
I've noticed a significant increase in fuel economy already, from around 11.6 l/100k to around 10l/100k. Early days yet, but it's looking good.
It feels punchier in the mid to upper range, and happier to rev out to the rev limiter.
Other main change Steve made was to advance the timing a bit. The map already in the Exede was apparently tuned for 95RON and had 'only' 1.5 degrees advance, so Steve took it out to 4 degrees advance. I didn't check if he meant 4 degrees advance on the stock 6 degrees retard (ending up with 2 degrees retard), or a true 4 degrees advance. I think it was the latter.
Photos of the installed Exede and the dyno print outs below.
KJ.
Note the nifty mounting bracket. A DIY job, $6 fencing bracket from Bunnings!
Different angle showing more detail of mounting bracket.
Check out the AFRs. Red line is stock ratios, very rich, blue line is tuned ratios.
Again check out the AFRs. Red line is 'base 380 map' Exede ratios, a bit too lean (over 15 in places), blue line is tuned ratios (same as previous chart).
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