I would get an ECU chip either from Australia or Lutz.

I did a test with mine this past week to see if there was a difference
between the triple electrode copper plugs Vs the quad tip platinum and the
stock ECU chip and the Aussie chip

When I put the triple plugs in, the mileage decreased a couple of miles per
gallon.

Then I changed chips.  Well, the engine ran rough when I first cranked it
cold, did not have the power to smoothly pull up hills at lower RPM 2000 to
2800, ran hotter the needle was at top of red led rather than at bottom
during driving and while idling the needle went above the led a quarter inch,
kicking on the fan, a lot quicker.  The engine just did not run as good. The
throttle was less responsive.  With the AC on the engine was slower to take
off needing more throttle to get moving from a stand still.  Mileage dropped
to 15 mpg around town, down from 20.

I put the Aussie chip and platinum plugs back in and the engine ran a lot
smoother.  Engine runs much stronger and smoother cold, power is back as
before. Accelerating was much easier from a stand still with the AC on. The
engine is running cooler, during the trip the needle was at the bottom of the
led.  When I was idling, the temp did not go up as fast with the stock chip.
Needed less throttle to get moving and shifting between gears.  Mileage
increased to 23 for my highway driving.

The Aussie chip does make the WBX run better, It might not add tons of HP,
but it does do what it was designed to do, make the WBX engine run better
than the stock chip.  It could have its limitations in that when you increase
the air flowing through the engine too much, the program is limited, BUT that
is where the ECU chip from Lutz might come into play.  It is designed for
higher flowing engines and has the redline increased to 6800 RPM, up from
5800 RPM.  Will test one soon...

Robert