Roush was forced into the valvespring business years ago for its racing engines when the company could not find high-enough-quality springs. That dedication to getting it right plays straight through to the streetable 200 head, which is offered with three spring options. The first is a 1.250-inch-tall single good for 0.560-inch valve lift and offering 280 pounds of open pressure. Shown is the midrange option, a 1.440-inch double spring good up to 0.600 inch of valve lift with 320 pounds of open pressure. The ultimate offering is 1.550 inches tall. Still a double, it can open 0.700 inch while giving 560 pounds of closing force.