On my '31 coupe, the intake manifold recently cracked pretty badly near the carburetor. I have no idea whether either of the manifolds on the car are original. I went online to shop for a replacement and bought what looked like a good one off of eBay. Claimed to be original, had the vacuum port for my wiper, etc.
I went out to install it this evening and the flange that you tighten the nuts down onto, is WAY thicker than the flange on my exhaust manifold. I didn't measure the difference but it looks to be around 1/8". The gasket mounting surfaces appear to be pretty much aligned, and the two manifolds bolt together just fine. It's just the flange thickness that appears to be off. I can't imagine the concave washer would even make contact with the thinner exhaust manifold flange, since it's such a big difference in thickness.
The new intake manifold looks a bit different from the cracked one I removed, and doesn't appear to have a molded-in bung for the vacuum port. Rather it looks like a port was just drilled and tapped into a normal manifold.
Where should I go from here? Should I pick up another intake or exhaust manifold in hopes of finding a matching set? Just bite the bullet and buy a matching reproduction set from one of the vendors? Also curious if there's any way to tell which of my manifolds are original vs. reproduction.
Thanks a ton for any wisdom you may be able to share.
