2806178 Intake Manifold Replacement - What Date Code do I need?

[Michael_]

Michael, you bought a vacuum gauge recently, right?
Have you hooked it up yet - that should clearly show if your intake isn't sealing.

Yes i did and it currently only reads 15". From what i've been told 17-18" would be normal.

 

[66 Sat]

I don't think 15" is an issue on an old engine if the needle is steady and the car idles and drives ok.
Have you tried spraying carb cleaner on the sides of the manifold where you believe it is leaking? Do it while the engine is running obviously - if the idle rpm increases then you have a leak.