1368cc F.I.R.E engine tuning

[Lugy]

Happy new year people of the Alfa/Fiat/Lancia sub, I'm building a new race car this year (Autograss Class 5), the engine has to be an up to 1400cc (well slightly over to allow for oversize boring) 8v.
The Vauxhall C14SE and PSA TU3 engines are most popular but I've since found some interesting articles about tuning the F.I.R.E engine.
From what I've read, albeit mostly aimed towards the 1242cc unit, they're very capable engines and respond well to tuning.
I have a few questions....
Does this translate to the bigger engine as effectively?
It's obviously a long running engine but are there any models I should try to avoid (eg late Punto)?
Has anyone used one in a competition setting before? If so, any words of wisdom?

Thanks in advance!