360 block casting numbers

[flamesoldier]

I just purchased a 72 Challenger and it has a 360. I crawled underneath to find casting numbers and they are 18496-5-360. Anyone know what years range this block is?

 

[Xcudame]

3418496 is 71-74 360. Supposedly these blocks have the 340 cylinder core meaning they're a little thicker and stiffer. The -5 just means it was poured in mold #5 although others believe the "5" means something else. Perhaps, but in every casting house I've been to, the molds for the same parts just have the extra number that acts like a serial number.

 

[flamesoldier]

3418496 is 71-74 360. Supposedly these blocks have the 340 cylinder core meaning they're a little thicker and stiffer. The -5 just means it was poured in mold #5 although others believe the "5" means something else. Perhaps, but in every casting house I've been to, the molds for the same parts just have the extra number that acts like a serial number.

Awesome thank you !