Yeah, they put water into the heads between the center two cylinders. Reason being is those two run so darn hot on a SBC...

It helps prevent detonation on those cylinders. It's common practice on roundy round stuff.

Doesn't really do too much though for over all cooling.

cooling 400 sbc
 

thanks guys i will just use the best of everything (rads, fans, water pumps etc and just have faith in all this good equiptment to do a good jobkeeping me cool thanks again guys for all your input chevy art PS what should i do for a radiator cap. i am using a good ron davis aluminum radiator 26x19 2 inches thick, mechanical fan with an aluminum shroud, good miledon water pump and HP thermostat, but i dont understand anything about radiator caps and usage of an overflow bottle. any suggestions would be appreciated about this chevy art

MAKE SURE YOUR HEADS HAVE THE STEAM HOLES DRILLED IN THEM.