You gave the key in your post.
That's the way to ask a question!
Considering your redline of 5500 and the use of 3.21 gears, I suggest an intake duration of
[email protected] And no more. The min. IMO would be
[email protected]. The intake duration is the key to the cams intended rpm range. A smooth idle is a cam on a 112 or 114.
Here is a Hyd. roller from Lunati that is something in the area that would fit your needs. You can use this info when talking to your grinder.
https://www.lunatipower.com/Product.aspx?id=3175&gid=289
