Although Tata Motors' 1.5-litre direct-injection turbo-petrol engine - first presented at Auto Expo 2023 - has been delayed for market introduction, the company has begun development of a new 1.5-litre naturally aspirated (NA) engine.

This unit is expected to be used in several upcoming models, including the Tata Sierra and a new compact SUV.

New Tata petrol engine line-up

Tata to offer five petrol engines across its model range

Currently, Tata Motors offers three petrol engines across its model range: a 1.2-litre naturally aspirated unit, a 1.2-litre turbocharged unit, and a 1.2-litre direct-injection turbocharged unit.

The launch of the 1.5-litre direct-injection turbo-petrol engine has been postponed.

According to sources, the manufacturer aims to make further adjustments before releasing it. This four-cylinder engine is planned for use in the Harrier, Safari, and the upcoming Sierra, with variations in power output based on the model and variant.

With the addition of the 1.5-litre NA engine, Tata Motors will offer five petrol engines across its line-up.

Entry-level Sierra to use 1.5-litre NA petrol engine

The new 1.5-litre naturally aspirated engine - likely based on the 1.5-litre direct-injection turbocharged unit - is expected to be used in the entry-level variants of the Sierra.

This would allow the model to compete with similarly equipped vehicles from other manufacturers. The Hyundai Creta and Kia Seltos are available with 117 PS 1.5-litre naturally aspirated and 162 PS 1.5-litre turbocharged petrol engines.

The Maruti Suzuki Grand Vitara is also offered with a 104 PS 1.5-litre naturally aspirated petrol engine in its lower variants.

The higher variants of the Sierra are expected to be fitted with the 1.5-litre direct-injection turbocharged engine shown at Auto Expo 2023.

At the event, the engine was stated to produce 172 PS and 280 Nm of torque, although different power outputs may be offered depending on the variant.