I understand the same intake manifold will fit the 331/354/392 motors. Weiand produced the 3x2 manifolds in limited numbers.

There is a difference in the block deck heights of the early Chrysler Hemis. The 331 and 354 are low blocks, the 392 is a raised block, this affects intake manifold interchangeability.

With the use of certain head/manifold combos the intakes interchange and there are spacers available for some combos.

Thanks John, good to know that info, so depending on the heads and maybe the use of spacers, this intake will fit these three hemi sizes? Do you have any photos of this intake or know if Weiand stamped a number on the intake or what that number would be if they did stamp them?

You can use any early Chrysler hemi intake on an any engine with stock (ie: correct year) heads... they all will interchange. In other words any Chrysler hemi aftermarket intake will fit all 331 and 354 blocks as long as they have 331 or 354 heads on them. Also the same intake will fit the 392 as long as the 392 is running 392 heads. The taller block of the 392 required Chrysler to make the intake surface of the heads thicker in order to compensate for the wider distance between cylinder banks. They did this so all the intake manifolds would be the same and they wouldn't have to make a special intake just for the 392. If you run a 392 with earlier 331/354 heads you will need to use spacers for the manifold to fit.

I'm running a Weiand 3x2 manifold on the '55 331 in my Deuce with stock '55 331 heads. They are rare intakes and expensive when you can find them.

Good luck.