Originally Posted by big_wasa

Ive built one of these hybrid st170/Zetec engines.

The idea being the weakest link in the Zetec is the rods and then the pistons. The St has better rods with bigger rod bolts and bigger small end. They are sinter-forged with fracture cracked big ends.

They finish up at 9:1
St bottom end. Full rebuild with Arp rod bolts.
new Blacktop head from a crate engine. It’s got the Hd valve springs.
Ford Rs 1.8mm gasket.
Raceline sump
Turbosport Rs flywheel
Subaru Td04L turbo
custom manifolds

running on the Focus Rs engine management.

Mt75 gearbox Ap racing Rs clutch.

And finally the one I am unsure on is the coolex intercooler and rad combo.