Welcome, I'm Chris (aka Moose). Experts aren't employees / agents of Just Answer. We are independent service providers using the Site to sell their Expert knowledge to Customers. I strive to provide EXCELLENT 5 STAR service, let me know what's needed from me so your pleased.
Both intake and exhaust springs take 34-39 ft lbs to crush them from free height to 1.390 inches tall.
First, the springs should close the valve immediate holding the lifter tight to the cam. You would have to be above redline engine speed to float the valves.
Second, Nissan does not give a degree measurement on the cams.
Third, Nissan does not give a duration spec.
Thanks for asking your question and letting me try to help you.
If your confused on why or how to rate me, let me know.
I'm only paid from the deposit you've made when you rate 3,4, or 5 stars.
Follow up/Reply as many times as needed before or after rating.