I was under the impression that the valve chambers were smaller in size on the SVT which made for the higher compression, which would mean shorter valves? I don't own an SVT so don't take my words as knowledge, but I do know that the SVT's run a higher compression, which is why the "Premium Fuel Only" appears on the SVT fuel gauge. If you run the wrong length valves, you are asking for worlds of problems. Check the info before you do this, because valve replacement is not one of those things you want to do more than once.
-Jeremy
