The TCE90 has a lot of torque.
The engine bay is small.
There's not much that would work,less that would give anything more than marginal power increase and I doubt anything that would fit in the engine bay and keep the back seats.
you'd need a Triple, V4 or small V6 or maybe some bike inline fours might work if a cradle has been desined for other similar purpose?
Yamaha VMax or VFR1200 are both V4 and would be the most obvious choice. Well only engines I can think of.
Ask why did Renault even develop the TCE90 engine?
I mean the Nissan had already developed the DIG-S which is marginally more powerful and marginally more economical. it has no lag because its Supercharged its even direct injection. Renault could have used it it's a great engine (unfortunately its only available in the turd of a car known as the Micra/March or the not much better Nissan Note.) It's likely the TCE90 engine was developed specifically with the Twingo in mind.
If you do attempt an engine swap I'm sure you'll find someone with an old Hilman Imp who'd gladly take that engine off you and make a really successful engine swap.
Last edited by gzee; 01-17-2016 at 02:40 PM.