What way is correct to do the subject manipulation ? Just usual interaction like tile.doSuff() or via packets ? My case is tile's rendering class that implements TileEntitySpecialRenderer. It has my TileEntity class on input (renderAModelAt) . I need to do it so i can change my tile's rendering system, checking tile's nbt. But it always works incorrectly.

NBT data is not synced between the client and server. So if you change anything on the server you will need to send a packet to inform the client that it's changed.

And how do I use these tile's methods  to notify client about nbt changes ?

@Override
    public Packet getDescriptionPacket(){
        NBTTagCompound tag = new NBTTagCompound();
        writeToNBT(tag);
        return new Packet132TileEntityData(xCoord, yCoord, zCoord, 0, tag);
    }

@Override
    public void onDataPacket(INetworkManager net, Packet132TileEntityData pkt){
        readFromNBT(pkt.data);
    }

public void sendDescriptionPacket(){
        PacketDispatcher.sendPacketToAllAround(xCoord, yCoord, zCoord, 64D, worldObj.provider.dimensionId, getDescriptionPacket());
    }

sendDescriptionPacket() is a 'homemade' method with which you can send the nbt packet to the client whenever you want. The fewer packets you send the better though. So the best that you can do is simulating the same behaviour on the client and on the server and only send a packet when you know the client will be desynched.

Thank you guys !!! SOLVED