Oooo yeah, just cuz Terry said it's not, means it's not.

I don't know whether it is or isn't, but one man's word just because he worked for ford doesn't decide it. And terry didn't design the zetec so I wouldn't take his word as the WORD on the zetec. And by that statement, it sounds like there is NO other interference engine made, which would be crazy or atleast no 2L interference engine, but I'm sure there is.