A 2.4 liter from the same engine family would be a no brainer for me compared to 1.6 from a completly different brand.
But your not thinking about replacements. When was the last time you saw one of those engines for sale? A whole MX5 can be had for less than £500. By the time ive sold the parts I don't need its free. I can doo all the installation work myself and just need a custom prop at £300. Id be getting a 1.8 at least not a 1.6
Another vote for the 4G63t. And there's even a nice handy build thread about putting on in a 'very' similar body shell. If you click the photo link below
Chris
Again not very common are they ? There isnt many starions etc around and tbh i wouldnt want to break a cool car like that any way!
To fit the bill the engines need to be tunable, good aftermarket support, plentiful in the case of breakages etc.
I would love to keep the engine in it or fit its larger counterpart but even service parts are thin on the ground let alone tuning parts unless anybody can show me otherwise?