I've dumped the water out of the back of my heads for years, but I run a crossover. Didn't know if it would effect the thermostat opening, constantly adding more cold water to the block.

with -4 line,and a t to 1 going overboard,it is not dumping much water,its all about stoping a steam pocket before it happens.

You definitely want to run SMALL line from the rear of the intake fittings. It's not for dumping water in volume, it's only for keeping air from "pooling".

In automotive applications, you HAVE to run to the front crossover. In a boat, you can do that, or dump overboard. Dumping overboard will bring more sea water thru the block, so you'll have to decide whether you run enough in (truly) cold water to matter. As stated, it will serve its purpose if you run the lines to the front crossover OR dump it out..

MC

to revive this thread a little bit, would a 1/4 OD tubing work to relieve the steam pockets?

Also, I would like to piggy-back my question on Waveform's, can you still do this if there are no rear water port bosses on the manifold? None of the Victor Jr's or Darts have them.