Create Aeronautics: Heavitite (pronounced HEV-itite) is a mod that adds a special levitite variant made of netherite that has a customizable weight once solidified.
To solidify the heavitite, just place any form of cold block adjacent to it and watch it (and adjacent heavitite blocks) crystalize!
Holding right click on the solidified block with a wrench allows you to increase the block's weight all the way from 4kpg to infinity! (though I'd be careful with a block that heavy.) This allows for compact, convenient weight distribution for vehicles and contraptions at the cost of some rarer resources.