Great to speak with you yesterday @Harlo and thank you for the recommendation, Chris!
A bit of general info… my understanding is that Clive at AutoTronix does the tuning for Rodders, and while he keeps hold of the physical cable, Rodders has the ECUTek license that is required, so both parties work together on this. This may explain why the package available is ‘manifold & map’, and thus juat mapping isn’t available separately. ECUTek doesn’t support the ND2 at this time, as far as I am aware, but the guys at VersaTuner have managed to crack it.
The ND2 is a tricky beast to tune. The ECU is considerably more complex than the ND1 - it takes 2-3 times longer to transfer a full map’s worth of data, to give an idea. Many of the tables are listed as ‘Unknown’ and figuring out what does what has taken a lot of time and help from a couple of guys I work closely with (Shaun and Sam if you’re reading, thank you! @The_Fonze ).
The OEM map on these is really well done, so while it is tricky to improve the power / torque figures (you might see a couple of ft/lbs and 5-7bhp top end - only really because of increasing the revs, because bhp is a function of torque and rpm), the driveability and smoothness can be improved, plus various functions and behaviours adjusted to the owner’s tastes. There are a bunch of things in there which are visibly aimed at reducing NOx emissions (at the expense of CO, CO2 and HC), which detrimentally impact the behaviour of the car mostly at low throttle inputs and tip-in / tip-out. Increasing the rev limiter and changing the behaviour from that weird ‘running into treacle’ sensation makes the car feel a lot more like an MX-5, and means you drop back into the revs higher up on a gear change. This gives considerably more ‘area under the curve’ when pressing on, so while the car wouldn’t display much differently on a dyno, the improved sensation and acceleration times on the road are noticeable.
The OTS (Off The Shelf) tunes within VersaTuner simply bump ignition timing by a ‘flat’ couple of degrees everywhere, and increase some load limits / torque request values. This has a tendency to make the knock sensor very active, pulling timing everywhere, and in the long term after the ECU has learned the behaviour of the new map can actually reduce power, torque and smoothness over OEM.
Hope that is interesting and helpful!