I've found a few references by Googling intake 3836922 that refer to 235 intake manifolds. May have also been used on larger 261 truck engines. There should be a 3 or 4 character casting date somewhere on the manifold formatted like B137 where B is February (A is January...) 13 is the day of the month (one or two digits) and 7 is the last digit of the year of manufacture.

I did find another number on the manifold F27 Then on the top opposite side of numbers I posted was 27