OK, here's the deal.

Car is a '06 IX MR.

I know tuning is a "necessity" when looking to get maximum power, because putting on intakes and exhausts and whatnot affects the fuel-air mixture in different ways, hence you need to tune to get the most out of the engine.

Usually cars with mods have "issues", as in they run rich or they run lean without a tune.

So I understand how this all works but here's my problem.

My car runs beautifully.

And I don't want to change it

I mean, there's not a trace of smoke, it pulls hard from every RPM in every gear (sometimes spirited jaunts on the freeway make it feel like it's going to break loose tires!) with no lag. Most importantly, when I was up racing at 6000-7000ft where my tuned STi and WRX had tons of lag and just general problems with the tune, this thing ran beautifully at that altitude. Sure, there was a little more lag than at close to sea level but not nearly as much as my STi had, and it just generally ran smoother and felt more powerful at that altitude than the STi did. The only issue I had at altitude was a little bit of compressor stall under 3000rpm.

Like I said, the car just runs beautifully. It pulls harder than my tuned 300awhp STi did with similar mods. It idles and cruises smoother as well. Some of that I'm sure is the inline layout over the boxer, but I can't imagine it would make THIS much of a difference!

So here's the dilemma. I don't want to tune it! I don't want to lose how this thing is running! I'm sure a good tuner could get me where I need to be, but I worry about altitude. All the tuners I know are around sea level. They tune for sea level. If I go to a tuner for higher altitudes, they are going to tune for that altitude and the car will run like crap again when I get to sea level.

And that's my problem. I know I ~SHOULD~ tune it, but I just have this feeling that once I do it will not run like it is now.

Here's my current mods:

Custom ETS 3.5" Racing Intercooler
ETS Shortest Route Piping
ETS Small Battery Kit
ARC Induction Box
Cusco Intake Pipe (replaces ribbed rubber hose from intake box to turbo)
Stock Boost Controller (completely untouched & unmodded, I routinely see around 1.5bar max on the MR stock boost gauge)
Sun Auto Hyper Voltage System
Sun Auto Hyper Force System
Mynes Engineering stainless tubular header
Stock Turbo
Invidia O2 Housing
Invidia Downpipe
Stock Cat (have a test pipe to go in)
Greddy Ti-C catback
Stock ECU (completely untouched & unmodded, it was however completely reset for every mod)

Is it possible that all my mods are complimentary and the stock ECU has just done an excellent job of "learning" the mods? I know that the ECUs are flexible and can learn quite a bit, but I never imagined they would learn this well.

So that's why I am at a loss. I know I should tune, but the car just runs so well I feel like tuning it will mess something up.

- Patrick

 

You will be fine with those boltons at the stock boost level. The only mod that would even concern me is the O2 housing because of possible creep due to the flow increase. Mine didn't. I suggest you get a dyno tune. It did wonders for smoothing out my powerband. The Evo is so rich from the factory you are practically throwing away HP and gas mileage at the same time.

 

But I get excellent gas mileage, around 27-28mpg doing all freeway.

So if I was to get a minor dyno tune at the stock boost just to make sure everythings where it should be, the car should still feel like it does now?

- Patrick

 

Patrick,
here's what i would do... just rent the dyno for a few pulls and get the AFR reading. As long as your AFR is straight and not running too lean at wot, then i would not mess with it. It shouldn't be more than $80 to do three pulls on a good dyno

cheers.
mike @ mynes

 

That's what I was thinking, as long as the AFR is good I'm golden.

I haven't had any knocking or detonation issues yet that I've seen. Maybe my ECU is a freak of nature?

- Patrick