273 with 340 exhaust manifolds
Somebody may have ground the numbers off, on some factory manifolds the numbers are on the inside where you can't see. In the foreground you'll see a stock 318 driver's manifold with the bell flange like yours:
Somebody may have ground the numbers off, on some factory manifolds the numbers are on the inside where you can't see. In the foreground you'll see a stock 318 driver's manifold with the bell flange like yours: