Just put in a B16 kaaz lsd trans that did not grind on previous owner with a brand new stage 4 competition clutch that is broken in, changed fluids, bled clutch, changed the master slave, and even have full race hasport motor mounts, and I can't seem to think of anyting else I can do to make 3rd gear stop grinding. Any Ideas?

 

It probably grinded 3rd for the previous owner. Only way to fix it would be changing parts that are worn for 3/4 gear.

Just delay your shift to 3rd for a small bit and try to have the rpm as close as possible to where it should be when you let the clutch out

 

re synchro it