they do.. but i've got one that i want to fill all the way... and just cool the heads... either that or i'm gonna fill the heads also.. 351.. planning lots of BOOST.. probably methanol so cooling isnt that big of a deal.. just thinking if i had to drive it for 2-3 miles. street type racing..Don't guys fill the block to the bottom of the core plugs and let the upper part and top end keep getting coolant?
i got a price on welding up the bottom of the head and surfacing back flat.. i would then need to decide to run dry.. or put some water in there and circulate through a tank... or radiator of some sort.. got 2 things in mind actually.. at most the car would have to be driven 3-4 miles.. and on that trip it includes and 1/8th mile blast .. shutdown.. turn around.. and then back to starting line or local gas station.. (car will not use gas.. just a meet up point.. car will be on alky)This is on import (4G63) motors, but when I concrete a block,, they'll pop a freeze plug on the (aluminum) head and run a line (-16, I believe) directly to it. Usually a solid copper head gasket that has been made specifically for a dry-decked block (coolant cut-outs have been deleted). IIRC the thermostat is on the back of the head, so that acts as the exit.
So yeah, you'd need to figure out where's a good spot to have both an inlet and outlet for the water.
Also, don't fill the heads, especially if it's going to be running for more than 30-45 seconds. Things will start warping.