1986 police engine

When using the 360 heads on a 318, doesn't that drop the CR due to the larger combustion chamber? Or do those heads have smaller chambers? I have 2 1988 318 engines that are complete. One is totally unmolested except for removal of the lean burn, converted to the HEI system. Bought new, and used as a daily driver.
The other is a (supposedly) cop car engine and trans. I got it as a complete Front end with the engine still bolted to the "K" frame, with steering and brakes. I have not dissembled anything, yet. It did have a carter competition series carb (adapter for the stock manifold) and a Mallory Unilite distributer in it. Also got the rear from the car. The rear is a 7 1/4 non SG. I don't want to take anything apart, as I use this engine for checking carbs, as it runs good.
PS: I found out about the oil cooler return the first time I fired the engine. Guess how? :)