We'd like reiterate that there's no official mention of the name 'Proton S50'; it is just one of the names trademarked by the manufacturer along with 'X90'. Leaving the mystery of names aside, its arrival on Malaysian shores inches closer, as exemplified by this right-hand drive (RHD) test unit.

Still about as masked as the last time we saw it, this new set of photos by The Ajerul affords us a better look at the cabin. Good news then as this particular car is RHD – just like the X90 from yesterday's article – which is a telltale sign that the car is in the latter stages of development.

Also read: Proton X90 nears production version, RHD mule with 'Infinite Weave' grille spotted

Questions on powertrain and prices are still blanks to be filled, but if Proton's continued focus into the engine is a clue, then expect it to feature some form of the 1.5-litre turbocharged three-cylinder that's in the X50 and X70.

A other key factor is the fact that the naturally-aspirated 1.5-litre unit doesn't have enough pulling power for the car's 1.2-tonne kerb weight. That means it'll have a 82 PS/tonne power-to-weight ratio, far less than rivals like the City (106 PS/tonne) and Vios (93 PS/tonne).

In July 2022, Proton officials also said that there are plans to produce more variants of the 1.5-litre three-potter, yet stopped short of mentioning details. Don't discount a mild-hybrid (MHEV) version as well; which could find its way into newer models too.

Also read: Proton X90 likely to be Proton's first-ever hybrid, MHEV already teased in COE

But humour us for a second and imagine the S50 gets the X50's engine verbatim. With 150 PS/226 Nm, it'll be Proton's most powerful sedan to date; slightly edging the 2.4-litre Proton Perdana (Accordana) of a few years ago. A dream?

We'll know more as 2023 flows, ahead of its prospective market introduction next year.