Sometimes I'm a little impulsive. I've done enough research on tuning options for the Mirage to know that there's not much out there SPECIFICALLY for the Mirage just yet. There are a few options out there, and a little more money than I wanted to spend.
Learned about the Volo tuner Friday night. Did a little research on it. And in a matter of a couple hours, I decided to go ahead and order one! There are good reviews out there, including from a website that tests "performance chips". They were very skeptical about it before they tried it, and they concluded that it does, indeed, work.
Part of my research included downloading the tuning software from their website and looking through the options. Between that, and reading some reviews and some Q&A from the company that I found in various places, I've concluded that this is how it works.
It's not a true "flash tuner". You don't just plug it in and flash the ECU and then put it in the closet when you're done. It doesn't overwrite the stock tuning, and it doesn't give you the option to do any sort of fully custom tuning. That's not necessarily a bad thing. Most people don't need that level of control.
What it does is modify the fuel and spark (and maybe throttle?) trim tables. It does this every time you start the engine because it's not permanently making changes to the ECU. Therefore, to use it, you have to keep it plugged in.
The options in the software are pretty straightforward, it asks:
- Year/Make/Model/Engine of the car (and their library includes a LOT of different cars... meaning that you could use this on more than just your Mirage, it's versatile)
- Performance Priority (Economy, Performance or Mix)
- Fuel Octane (87, 89 or 91+)
- Towing/Hauling (never, sometimes, always... I'm not sure what it does with this... throttle curve?)
- HHO (do you have it or not... insert eyeroll)
- High Flow Air Filter, like K&N (yes or no)
- Cold Air Intake (yes or no)
- High Flow Exhaust (yes or no)
- Exhaust Header (yes or no)
- Ignition Mods (yes or no)
- Underdrive Pulley (yes or no... not sure what it does with this, either...)
And then, it appears that it sends the following info to the module (via USB) depending on your options:
SET PRIORITY P
SET FUEL 2
LOAD OFFSET 0
HHO ENABLE F
FUEL OFFSET 1 0
FUEL OFFSET 2 0
FUEL OFFSET 3 1
FUEL OFFSET 4 1
TIMING OFFSET 1 0
Guesses as to how that works:
Priority - this one's obvious, and your priority probably mostly affects throttle control
Fuel - yeah, it's going to add more fuel... I guess to the second level...
Load Offset - This probably has something to do with throttle control, as well
HHO - Presumably injecting HHO would reduce the fuel requirement and allow greater timing advance, but I don't care, not something I'm into
Fuel Offsets - These are probably different RPM and/or load ranges. Where to apply the increased fuel?
Timing Offset 1 - The level of timing advance over stock.
Would be cool if they just said what all of these things are and allowed you to manually set each one if you wanted to, and what their range of operation is. (and maybe they do, there is a "load custom map" option, and maybe the kit comes with a manual?) If they don't, then it will just take some experimentation to see which options affect which variables.
So, while this isn't going to be anywhere near as effective as a full dyno tune via flash tuner, piggyback ECU, or aftermarket ECU -- it does allow a little bit of tuning, and should be better than nothing.
For about $138 shipped... it seemed very much worth the risk. If it gets me a little bit more from the exhaust mods that I've already done, it will totally be worth it.
The only thing it doesn't appear to do that I would like is to raise the rev limit, even just a little bit. For autocross, being able to reach a higher speed in 2nd gear without having to shift to 3rd is always welcome. A couple hundred RPM can make a difference. After playing with it, I may contact Volo and ask if this is something they can do. Maybe they can add it to a future release of the software? (or maybe it's an already available "custom" option?)