BB exhaust manifolds on my Dart

[Popdart]

I need some help with my exhaust manifolds.  I bought the car, 73 Dart, with a 383.  Has exhaust manifolds but thats all.  I'm in process of trying to get it on the road only to find out what I have and what it needs.  Question is, I looked for casting numbers to see what I had, and they are as follows: 3751068 drvrs side, and 3751074 pass side.

I realize this doesn't match up with any pre 70 BB A-Body engines.  On a internet search, it shows some references to 400 applications after 72.  Anyone have any info on these manifolds?? Any pros and cons?

Thanks Rog

[Popdart]

Well I did find some tech info on castings at:

http://cache.search.yahoo.net/search/cache?ei=UTF-8&p=400+exhaust+manifold+3751068&fr=slv1-&u=www.mopar1.us/exhaustmanifolds.html&w=400+exhaust+manifold+3751068&d=QwJX8Rg5RJKD&icp=1&.intl=us

It shows they're from 73-74 400 or 440.  Now the question I need to answer is if it is a 383 or 400.  Any easy way to tell?

Thanks again, Rog

[Joe67GT]

I looked and all I came up with was B/RB B-body 1973.
Here's a link, at the very bottom. I can't find the 3751074# though.

http://www.autohobbydigest.com/tables.php?05_Manifolds