348 heads with a X casted in the center of heads?

[RodFather]

I have a set of 348 heads that i just pulled off a motor and noticed a X casted in the middle of the heads and had not seen this before .

 

[Don Jacks]

What are the casting numbers on those heads and what are the casting dates please?

 

[RodFather]

3758379 280 hp date 5 59 I took it out of a 60 impala which i still have.

 

[RodFather]

Just was wondering about the X in the middel of the head.

 

[chevytaylor]

Photo?

 

[RodFather]

Here is a pic of the heads.

 

[oldskydog]

Like these

.

 

[RodFather]

Yes