1990 B18a1 block

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Junior Member
Ok I bought a complete swap (97 B18b1) I was going to put in my car(97 civic hx)
OK well I got a deal on this dart sleeved block(1990 B18a1) I want to use this block for the swap I also have piston and crank.
Well the A1 has a hole on the back on the bottom right side of the block, I was told it was for a breather chamber.
The 97 B18b1 has no such hole in the block.
My question is Can I still use the b1 head and intake manifold with the a1 block do I need this breather chamber or can I just seal off the hole and not use one?


That was for the old pcv system. you can simply run a hose form the IM to the valve cover directly and figure out a way to block the hole up.