Originally Posted by M3PO
Just a bit of anecdotal evidence but Tom immediately suggested this as the "problem" and said he had seen this before. In fact, he showed me the plots for a car that made 308 WHP (stock) with old plugs and software. It was misfiring and had failed smog (not codes though). The updated software made a huge difference (I wanna say it made 345 after updating the software but don't quote me on that).
This is the answer I was looking for, as not every situation will play out the same. This shouldn't be approached as a "mod" but as a part of regular maintenance.
Let's explain things a bit:
M3PO's M3 was strapped to the dyno for Evolve software tune to perform a before/after dyno just to show approximate gains that would be as a result of flashing evolve-r software. After a few baseline runs, it appeared to be down on power for the specific mods that were installed. We really didn't even get a chance to test the new evolve software.
Thus, the troubleshooting process begins.
Since this was a 2008 model, there are a number of things to consider since miles were racking up. Spark plugs were recently changed, so we can rule those out as a possibility.
Other than running the car on the dyno some more and logging O2 activity, a VIN check was the next logical step, which showed that updates were performed shortly after purchase, or possibly not at all. A DME read showed early software (100E), which prompted for an update (231E), as we've seen considerable gains from this in the past on a number of early vehicles. After updating, M3PO's car showed normal power levels on the dyno again.
It's a good idea to keep current with updates, but dealerships will not update (for free) unless there is a considerable reason to do so. What I don't want to recommend is everyone calling their SAs and demanding updates on Monday morning - as every situation is different.
Best advice? Get a baseline dyno beforehand to eliminate the guesswork. Also, keep up on maintenance.
Brent: We'll see you on the dyno soon in the search for more power.