Vintage aluminum intakes. Q&A

[J-MacsMopars]

Hey everyone. I have a few questions about vintage intakes.
Number one;
On a LD340 intake that I have, it has 2nd stamped into it. Any idea why? I wouldn't think that Edlebrock would sell a junk intake?
Number two;
Has anyone ever seen an Offenhouser Dual-Port 360 intake before? Are they any good?

Thanks,

 

[jaws]

My LD dosen't have a second stamp on it, so your guess is as good as mine. Had a dual port on a 318, nothing to wright home to mom about.

 

[Mr.FT]

My LD 340 doesn't have 2nd any where on it either, I would contact Edelbrock and ask them.

 

[gtsjim]

Had about 5 LD 340's before and never saw 2nd stamped on any of them.

 

[ocdart]

I ran an Offy Dual-Port 360 on my '69 340 Swinger years ago. Good street manifold at the time. The theory was good: small cross-section runner portion kept the primary intake charge at very high velocity for good cylinder filling; larger cross-section runner was isolated somewhat from engine heat so provided a cooler secondary charge when the secondaries kicked in. The drawback was at the higher rpm ranges due to the total reduced cross-section due to the material separating the primary and secondary runners.
40-year newer technology makes for better manifolds available today.