So what does a Gil style manifold cross section look like? Do they have vacuum breaks? Wondering why he automatically dismissed them from the conversation. Thanks for posting this Sprink.

No dam. They revert easily and are not a very good manifold hp wise, especially NA.

my old 454's beg to differ.

Old 502's like em too.

They are begging.

were,,they went into street rods.still running.