Streetmaster 318
Is Single-Plane Manifold with narrow runners.
For a 'stock' 318, it is a functionally useful Manifold, that will
give you decent performance in your power range.
Specifically designed for the 'low-to-mid' range power band of up
to 4500 RPM's.
Also, the ports will line up well with your 318.
The Edelbrock 318 Streetmaster came thru with a Square-Bore carburetor mount. That would be the choice for the 600 Holley.
Also, it is a sharp looking Aluminum Intake.
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The 1971 340 Intake, is a great unit. But, it has a Thermoquad Carb mount, and has larger runners........
It would not be my choice for an 'all stock' 318.