340 block question

[trudysduster]

I was looking for a 340 block for my 73 Duster and found a guy who had a std. 69 short block and he also had a 70 bare block that had no main caps. He also sold me in with the deal a complete 70 318 engine with an aluminum 904 attached to it. The crank in the 318 should be a steel crank and if it is, can I use the main caps off of the 318 and send the block to the machine shop and have it line bored. The two engines have the same size crank so will it work. I also need to know if the rods from a 318 and a 340 the same. I have not tore into this 318 yet but I am curious if it will work. Thanks,Bill

 

[340mopar]

The 318 is most likely a cast crank. I have never seen an LA 318 forged crank but other people on here say they have (who am I to say they didn't) that is why I say most likely.

You should be able to use the 318 caps. But only if they fit tight on the sides. If they are loose on the sides then they won't. Some 318's did have floating pins like the 340 so those would be the same.


Chuck

 

[70aarcuda]

some of the 318 truck engines had steel cranks...

if you use any main caps other then the ones that came with the 340 block the mains will need to be align bored or honed with the new caps.