Any gains adding 1.6 rockers to stock 273?

That is a 64-64 LA 273 intake. There are people looking for one of those. @eekvonzipper is one. Offenhauser 5489 Offenhauser 360 Degree Single-Quad Low-Rise Intake Manifolds | Summit Racing

These are Poly intakes, each runner is individual.

https://poly318.com/poly-318-intake-manifolds/