Yes, you can tie dye a 60 40 blend. The process is essentially the same as tie dying any other fabric. To get started, you'll need a piece of 60 40 fabric and some tie dye supplies. You can find both of these things at your local craft store.
To start, soak your fabric in a solution of warm water and white vinegar for about 30 minutes. This will help the color to set better. Once your fabric is soaked, wring it out and lay it flat on a surface that you don't mind getting messy.
Next, choose the colors you want to use for your tie dye project. To create a 60 40 blend, mix two complementary colors together in equal parts. For example, you could mix red and yellow together to create an orange hue. Once you have your colors mixed together, apply them to your fabric using whichever technique you prefer.
After you've applied the color to your liking, allow the fabric to sit for about 30 minutes so that the dye has time to set. Then rinse it out in cold water until the water runs clear. Finally, wash it in your washing machine on the delicate cycle with cold water and air dry it or tumble dry it on low heat.