What are you using to determine its over heating? A real gauge or the dash gauge?
Tell us all about your cooling system. Radiator, shroud fan type, water pump, etc.
Does it cool down while driving? What is your tune? Do you have AC?
No driven miles, engine just drop in. no AC, thermostat 1/8 hole drilled, water flow good, timing set at 12 degrees advance, new water pump, using a real gauge no in dash, also Lazard water temp, rad. re-core, also did a block test in water its test fail exhaust is in the water, top gets really hot over 210 and keeps climbing and have to shut it down. any info would be greatly appreciated.