Hello: I'm trying to identify a pair of ram's horn style exhaust manifolds. The casting number for what I think is the RH side is 3747047. The casting number for what I believe is the LH side is 3733876 (very hard to read this number due to rust). Can anyone help out? Thanks!

------------------

I don’t know if this will help, but here goes: First could the RH # be 3747042? In the book Chevy by the #’s (“70-“75) they have a listing for a #3932465 as being similar to the #3747042. It says that it was used on 1970 (and 1969) passenger 350’s and 400’s and on Corvettes w/ 350’s. I have no listing on the other # that you listed.

Correction;

3747042 - RH rams horn ex manifold

1965 Passenger 283/195hp
1965 Corvette 327/250hp & 300hp auto trans w/ac
1966/67 Passenger 283/195hp and 220hp w/o A.I.R.
1966/67 Passenger 327/275hp w/o A.I.R
1966/67 Corvette 327/300;350hp w/o A.I.R.
1968 Passenger 307/200hp with auto trans
1968 Passenger 327/250 and 275hp

On the LH, the closest number I can find is 3932473 which is curved outlet type:
1969 Passenger 327/235hp w/auto with A.I.R.
1969 Passenger 350/250,255,300hp manual trans with A.I.R
1969 casting was tapped for A.I.R
1970 Passenger 350/250,300hp w/o A.I.R.
1970 Passenger 400/265hp
1970 casting was not tapped for A.I.R.

Thanks for the info Z28Mark and Jonesy!

------------------

I have a exhaust manifold with this number . The date code is K 2
Does this mean 1972?