Originally posted by ZetecRacing:
Originally posted by Dan Nixon:
FWIW (as I am not a zetecer) I think a (the) key problem with zetec is the small valves relative to cylinder displacement. The SVTF head is new with big valves and big ports...could maybe get SVTF big valves (with upgraded springs & retainers) installed with appropriate porting.. zetec intake manifold looks bad as well, the variable runner style SVTF intake looks nice (and NOT like the duratec). cams as hot as you want next.. Now you are cooking..Well the nodular iron crank may be an issue over 8-8.5K?? rods, pistons..thats alot of cash guys..
1 the valves... Esslinger makes much better oversized valves than the ones found on the SVTF
2 the crank.... it can handle upto 8000+rpm stock. higher yes I would replace it
3 what sucks is we have to replace the stock mainfold if we want better flow from it unlike the duratec we can't extrude hone it cause ford was nice enough to give us plastic 
that and the thing looks like a maze
Focus Central (www.focus-central.com) ports the Zetec intake manifold. Yes it is pricey ($250 plus $170 core) but it has shown gains of 10 hp on some cars.
