What's up with that gap?

So all I've ever messed with is small blocks. Noticed this the other day and haven't found anything on why it's that way. Car seems to run just fine so is it bad or...

Normal. I’m not exactly why the heat crossover is designed that way. But don’t worry about it.

I would say that it is to dissipate heat.

Its part of the heat crossover to warm the plenum on a factory intake. Most aftermarket intakes do not have the corresponding upper passageway, or have no passageway at all. Some intake gaskets will cover it completely.

I've run my junk like yours is setup with no problems. That exposed passage will attract crud, but that's about it.

All the OEM iron BB heads except the Max wedge heads have that feature built into them to help reduce the heat from the cross over passage from the passenger side of the motor forced to the drivers side with stock exhaust manifolds to help heat up the intake manifolds
I don't think Mopar or any other of the car makers have that feature on any other motor

You're all wrong, it's the equivalent of Limbo for small items you accidently drop.

John you're the man (as always!).

it is as the factory intended. a place for small items you desperately need to be stored [in a safe place], or to make you think you dropped down the carb port, forcing you to tear down the top end, only to find nothing !

By the way, your small blocks were that way, too...

Carburetor linkage retainers/clips for example

( don't ask me how I know it )

It's also where you store 1970's grit and goo.

Old timer told me that's where he always shoved his cigarette butts.

Never really noticed. Intake always covered it I guess. I wanna say thanks Jim, went back a looked at the picture and seen I have a carb leak. Great...