Re:Re:Best Tuning program to start tuning?

Megasquirt can be set to control VVT. The whole Megasquirt platform is adaptable.
The basic kit may not control VVT but you can add and adapt it. 1st setup I saw was on an 1100bhp Toyota Supra. It had been set up and mapped to run electric water pumps, nitrous, water injection etc.

You can damage the Cat with a Megasquirt kit but you would have to set it up to do so. If you have built something with a cat, setting the megasquirt up to maintain lambda is no different to using the standard ECU. Would you really be setting an engine for optimum fuel ratio with the standard cat?
Set incorrectly you could also damage the engine advancing the timing enough to cause pinking but again, who would go to the trouble putting together a Megasquirt kit and not bother using a knock sensor?

Would you want to keep the VVT anyway? On modern engines VVT is more to control emissions rather than performance. If you are at the stage of spending the time and money to setup an ECU you will have an idea what you want to use the car for and when you need peak power or torque. Setting the cam timing with solid pulleys and junking the VVT will reduce reciprocating mass and increase power.

Back to the subject, having your ECU remapped (or making your own Megasquirt one) will probably give you better performance if the reprogrammer knows what they are doing but fitting a bigger M16A is far less hassle!

Found this...

danstengineering.co.uk/Suzuki-M13A-M15A-...Package?search=jimny