that is correct. ford's badging is very confusing. the st170 and RS are actually rebadged zetec's but the st170 engine does run vvt and has probably one of the best flowing heads you could fit to a zetec engine. its probably the most "tuned" duratec in NA form. I think the Mazda 6 MPS has a turbocharged 2.3 duratec and produces 256bhp. Same with the Mazda 3 MPS if my memory serves me correctly