In looking at the pictures, the NOS manifold doesn’t look to be molested. I’ve a healthy stack of those intakes here and not all have legible casting numbers on their bottoms. That’s simply an issue with the mold when they are being cast. As far as the price, it is ‘new’ and that by itself demands a premium. In this particular case, considerably more. It’s apparently worth it as that’s what it sold for.
While I haven’t quite completed the dual quad testing, the 1957 Ford 2X4 manifold ends up being a well engineered piece when used with the factory carbs. All the dual quad manifolds tested on the iron heads ran respectably well and especially if compared to the same engine running the ECZ-A intake and a Lincoln Teapot carb. If a dual quad setup was replacing that particular single four setup, then just bolting on the over the counter dual quad setup would have been an easy 45HP bolt on. When the ’57 dual quad setup is bolted on in place of the ECZ-B intake with a 750 Holley, there was only a 10HP gain. But the baseline for this test was the Mummert 1X4 intake with a 750 carb and so far, only a modified 1956 Mercury 2X4 intake has even come close.
But there are some other surprises cropping up out of this dual quad testing. When the aluminum heads were placed on the engine, this became a ‘true’ intake manifold test as now any flow issues within an intake do come to the forefront. And the factory dual quad carbs are suddenly undersized for the aluminum heads as the larger Ford Teapots, Lincoln and Carter carbs do work better with the aluminum heads on the engine. While I haven’t entered all the data in the spreadsheet yet, the Edelbrock 257’s may not have the superiority in performance that all have been led to believe. While not a slug, some of the other intakes do perform almost as well. More on that when testing is complete and I summarize the data.
I’ll add that at this point I’m getting rather adept at soldering up the extra Teapot secondary jets that are on hand and redrilling them to smaller sizes. Not quite something I planned on being good at but I guess it goes with the territory.
Lorena, Texas (South of Waco)