Honestly, I'm not sure! I keep small sandwich pieces (with fabric and batting) for sample pieces before starting on my quilt. I begin with a mid range tension and adjust up or down, depending on how the stitches look (make sure you are using the actual threads you will use on the quilt, especially if you use different colors on top/bottom). Bascially, you want to make sure that top thread color doesn't pull thru to the back (and visa versa). If you're not sure what that would look like, play around with your tension and it should be pretty obvious. Also be very conscious of "pushing" your quilt thru as well the drag on the quilt as I've found both will distort your stitches. Good luck!