Contour Enthusiasts Group Archives Forums Modifications 3.0L Duratec Cut and Dry - which kind of hybird (or straight 3.0) is better

Couple of points.
1) if going to 35mm valves with either 3L heads or 2.5L with porting and 3L valves would have the upper intake Extrude Honed to about 34mm as well (stock SVT UIM is 30mm primary and 32mm secondary). No point in having big valves if runners are to small. 99+ SVT lower is already 33/34mm.

2) the 35mm valves on 3L are proportional to the 32mm valves on 2.5L. Substantial gains going to 35mm valves on 2.5L (all the touring cars do this) so the HOT set up for 3L may be about 37mm perhaps. Maybe worthwhile if really going all out to have custom 37mm valves made.