Sometimes with new clutches you also need to "seat" the shoes to the bell if you did not replace the clutch bell as well. Just hold the car or truck on the ground and in place with the engine running....and pull full throttle for 2-3 seconds a few times. This will wear the shoes into the bell a bit and help with engagement.
You can also look at the clutch bell and see if the shoes are coming out to meet the bell properly with the engine running. If you rev it up a little...you should see the shoes moving to catch the bell. Does it engage with the wheels off the ground at all? No matter what springs are in there (0.9 - 1.1) they should engage and move the shoes....just at different RPMS.