Convert 1300 to 1600 dual head.
Head of 1300 F engine to rewrite the hole cylinder (1300)89.-- to (1600)93,-- whether the head wall will be thin.
This conversion reduces the 7,5:1 to 8,8:1 CR .

And normally I use a turbo.

That's increasing the CR not reducing it.
You don't wanna go too high if you're turboing it.

If you want to swap to twin port heads you'll need to swap out the stud kit amongst a range of other things - tinware, inlet manifold etc.