354 Poly block

[kirk]

I have a 354 Poly Block with casting #1819828 (forth and last digits could be either 8 or 9 - hard to read). Serial number is C75-1632C J46. I think the J46 is for Oct. 4, 1956, but I have not found information on the casting number or serial number.
Also have heads with cating number 1556157-1 (1955 - 331 cid). Can these heads be used on the 354 block even though the bore of the head is smaller than the block? Any help appreciated Thanks
Kirk

[macx]

If I remember reading correctly, the poly engines
were basically the same block as the hemi's but
with the cheaper to make poly heads.

I think this site has lots of good info.

http://www.hothemiheads.com/
http://www.geocities.com/MotorCity/Track/4164/

[Chrycoman]

I have a 354 Poly Block with casting #1819828 (forth and last digits could be either 8 or 9 - hard to read). Serial number is C75-1632C J46. I think the J46 is for Oct. 4, 1956, but I have not found information on the casting number or serial number.
Also have heads with cating number 1556157-1 (1955 - 331 cid). Can these heads be used on the 354 block even though the bore of the head is smaller than the block? Any help appreciated Thanks
Kirk

You have a Canadian (C) 354-cid V8 for a 1957 Windsor (C75). If the "J46" is for the assembly date, "J" would be September as Chrysler did not used the letter "I" - can be confused with the number "1". It is the 632nd 1957 C75 354-cid V8 built.

The heads, though, are from a Dodge Truck 331 hemi with 1.94" intake and 1.75" exhaust valves. And the heads will work on the 354 block. A smaller bore in the head will always work. It is when the bore in the head is larger than the engine bore that you have problems - the valves striking the block when they open. That valve size, by the way, was used on the 1956 New Yorker and Imperial 354 hemi. So the heads should work on that block with no problems.