When I was looking into zetec tweaking, pretty sure that Paul Dunnell told me a 1.8 head couldnt go onto the 2.0 bottom end. I had one in the shed (still do if anyone wants it) & asked if he could mod this to suit, whilst I still had the unmodifed 2ltr one running in the car. A polite but firm NO was the answer. Something to do with piston height & combustion chamber size. As the 1.8 bore is smaller (80.6 vs 84. i would presume it raises the CR beyond acceptable limits.kevp wrote:The Valves in the 1.8 zetec are the same as the 2.0, as are the cams (after-market). So you could fit the existing head to a 2.0l bottom for easy/cheap power/torque increase.
Identification wise - Wiki says this... The Zetec (SILVERTOP) can be identified by having a silver cam cover with "DOHC 16v" on the bottom left. The Zetec-E (SILVERTOP) has "ZETEC 16v" on the bottom left, and the Zetec-R (BLACKTOP) has a black plastic cam cover. The Focus RS and ST170 (SVT) are both Zetec-R engines, despite being branded Duratec.