The advanced Zetec-SE (sometimes badged as Zetec-S) was developed in collaboration with Yamaha and Mazda, under the Sigma codename.
It ranges in size from 1.2 to 1.7 L (1,242 to 1,679 cc).
It is very different from the Zeta engine – the intake and exhaust are even on opposite sides.
It was the first engine to use a plastic intake manifold.

This engine is sold under the Sigma name in some regions, while Mazda uses the MZI name.
 It is also sold as a crate engine by Ford Power Products as the ZSG.

From 2002 on, Ford started to badge their engines as Duratec.
 The 1.7 L version was dropped when the production of the Puma ended.
Now the 1.6 L is also available with variable valve timing, known by Ford as Ti-VCT (Twin Independent Variable Camshaft Timing).
The advanced Zetec-SE (sometimes badged as Zetec-S) was developed in collaboration with Yamaha and Mazda, under the Sigma codename. It ranges in size from 1.2 to 1.7 L (1,242 to 1,679 cc). It is very different from the Zeta engine – the intake and exhaust are even on opposite sides. It was the first engine to use a plastic intake manifold.
This engine is sold under the Sigma name in some regions, while Mazda uses the MZI name.  It is also sold as a crate engine by Ford Power Products as the ZSG.
From 2002 on, Ford started to badge their engines as Duratec.  The 1.7 L version was dropped when the production of the Puma ended. Now the 1.6 L is also available with variable valve timing, known by Ford as Ti-VCT (Twin Independent Variable Camshaft Timing).
Ford Zetec engine