I've seen LD340 intakes with a Chrysler part number but didn't know they did the same with the LD4B Edelbrock intake. Is this normal and why would an aftermarket 318 manifold have a Chrysler part number on it? Most 318's came with a 2 barrel, right?

Yes, I have seen them before with that number. Do a google search on it. Should be 318 small port. Probably was sold thru the Hustle Stuff or Direct Connection programs. My 318 ran great with that intake back in the day. It`s a keeper.

Over the counter part. They had one for the early and later model 273

Back in the late 60s and early 70s, maybe longer, Chrysler sold a lot of name brand performance parts through their Direct Connection system. Chrysler's attitude was these companies put a lot of effort into making their parts the best on the market, so by offering the name brand parts to the people that owned Chrysler powered cars, Chrysler wouldn't have to invest money in research and development. They could just add a Mopar part number, and sell the best parts through the performance division. There was a pretty impressive list of big name aftermarket suppliers you could buy parts from through your Mopar dealer. Gene