[KULTULZ]

Let me try this again as I did not answer all the questions in the first reply-

Originally Posted by JimNNN

Hi. I've decided my 1961 Monterey with the 352 is finally going to get it's cracked pass. side exhaust manifold replaced. I find manifolds online that supposedly will fit my car...and other early 60's/late 50's applications, but none of them have the same casting number as mine. My current (cracked manifold) casting number is 5751204, which doesn't seem to fit the typical Ford numbering scheme ("C" prefix, etc.)

-How much should I pay attention to the casting number?

The CASTING ID NO is going to tell you exactly what it is and cast (CASTING DATE CODE). FORD when making progressive component changes, usually (not always) changed the CASTING ID NO but the CASTING DATE will be a dead give-away as to the period.

-Are all pass. side manifolds for 352's from that era going to fit my car?

It is best to go by the FORD MPC and OSI CATALOGS (or an HOLLANDER INTERCHANGE MANUAL)

-My current unit has a heat actuated flapper valve. One of the used ones I'm looking at doesn't have a flapper valve. Would that be a problem using a manifold without a flapper valve on my car?

It is named a HEAT RISER VALVE and there were different deigns. You also have to make sure the CHOKE STOVE design is the same or you will have to modify the hot air choke tubing.

I do not have access to my 1960-64 LM MPC but the FORD MPC shows C3SZ 9430-A for the FORD application. MERC of this period was an exact duplicate usually. The PN shown is a SERVICE PN and not an ENGINEERING NO.