From what I've learned w/ my 340;

Torque is the name of the game and a stock stroke 340 doesn't make much down low, so you have to spin it, and of course to spin it you need spring pressure and a cam that works in that rpm range( Im gonna say upwards of 8000 rpm)

If I had to use a stock stroke in a 340 to run 10sec., I'd use a solid roller cam, but still consider a solid flat tappet. Cam timing is everything.