2008 BMW 135i: Full-on Dyno Comparison Geek-out
June 21, 2009
As mentioned previously, my keenly-honed butt accelerometer had me curious about the acceleration results we measured. Said the cheeks, "you introduced too many uncontrolled variables for a proper apples-to-apples test, dummy."
I'm usually concerned about voices that come out of my posterior, so to quell them we spent a few hours at MD Automotive in Westminster, CA. The goal? To shed a brighter light on the degree to which DME Tune's reflash pumped up our 135i's urge.
There, proprietor Mark DiBella rented out his Dynojet chassis dyno to us for the afternoon. In fact, anyone can rent his dyno. Mark's swell like that.
What's that? You want less rump talk and more dyno charts? Jump, then:
Here's how it went down. We dynoed the DME Tune configuration first, conducting as many pulls as necessary to achieve a stabilized result
Then Scott from DME Tune reloaded our stock calibration back into our 135i while it sat on the dyno, and the process was repeated.
As per our standard procedure, these runs are uncorrected for weather as the 135i is turbocharged.
Click the thumbnails for a larger image.
Stock DME Tune Stock vs DME Tune
Initially there was a strange dip in the DME Tune torque curve between 5,000 and 6,000 rpm. More ignition timing was gradually fed in during subsequent pulls, however, as logged by our DrewTech DashDAQ OBD-II magic black box. A little timing goes a long way in a boosted car, and with every dyno pull the engine controller filled in the hole a bit at a time. The stabilized, repeatable result is what you see above.
Clearly, the gains provided by the DME Tune reflash are substantial everywhere in the rev range.
Peak power swelled 55 horsepower compared to stock and peak torque jumped up 67 lb-ft.
All of these gains came from remapping spark, fuel, cam timing and boost; all hardware on the car is still stock. Aren't turbo engines great?
The DME Tune reflash also increases the rev limiter from 6,500 to 7,300 rpm. There's such a thing as diminishing returns, though. The dyno chart reveals that reflash's power falls off hard after about 6,800 rpm. Winding it out much past this is good only for, say, saving a shift while at the track.
Finally, here's the DME Tune reflashed 135i compared to our long-term 2009 BMW M3 :
Of particular note is the difference up to 6,700 rpm. Discuss.
Jason Kavanagh, Engineering Editor