Question of design....

I meant to ask a while ago, I was doing a lower intake gasket on a 350 not too long ago and noticed that the rear two cylinders' coolant passages are blocked off. Why is that?

I meant to ask a while ago, I was doing a lower intake gasket on a 350 not too long ago and noticed that the rear two cylinders' coolant passages are blocked off. Why is that?
Not needed on the iron headed engines. The aftermarket intakes have those passages open for more even cooling with aluminum heads.

all of them are like that.....both iron and alum.....if you get the right intake, you can put heater hoses to those ports.....and then just cut out the gaskets, if they don't have those holes...

Check my sig.....everything is cast iron (block and heads)...and i have an alum intake that has bosses to screw in hose adapters to run the heater hoses out....u do not have to use alum heads to get that...I am not!