flathead intake manifolds- Identifyiing?

What are the visible differences between the 38-48 (what I need) and the later intakes?

Someone help me out so's I dont end up with the wrong one

 

Hi kidwired! Easy stuff! Look on the left side forward and if there are two holes (or one hole and a large diameter "angled out to the side" oil filler tube) it's a later manifold. The forward hole is for road draft tube which the earlier engines didn't have. Regards, Dave.

 

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both of the single 4 bbl manifolds at the top of this page are the later 1ntakes even though the oil fill and road draft tube holes are in different locations. The earlier manifold won't have these as Dave said.

 

If you buy the later intake there is a plug that can be used to block of the road draft tube. HRP

 

you can use the later intakes , as people have said , just block off the holes and your in business. I used welch ( freeze) plugs just go to your local parts store and get some that fit and a little silicon and your in business.

 

I don't know if this is true for aftermarket intakes, but I've heard that the later ones hold the carbs at a different angle. I don't know if it would make a difference, though.

 

Early has carb pad at an angle to engine, late is parallel. Carbs are level in stock installation in both, engine mount angle is different between generations.