formulea for adding top 4 numbers out of row of six

I have the following formula for adding only the highest four numbers out of a row of six,=SUM(MAX(LARGE(B8:G8,1),0),MAX(LARGE(B8:G8,2),0),MAX(LARGE(B8:G8,3),0), MAX(LARGE(B8:G8,4),0)) but when only 3 numbers are filled in does not work unless a zero is inserted in at least one other cell in group, I thought that the ),0)) would show empty cell as zero, any suggestions would be most welcom