Need some info - "318-3" engine

-
P

PA Dart Guy

Well-Known Member
Joined
Jun 21, 2006
Messages
62
Reaction score
2
Location
Nottingham, PA
ok, from what I've read, the early truck 318 engines designated "318-3" on the block casting had a forged, hardened crankshaft...

I just picked up a 318 that is supposedly the original engine out of a 73 Cuda. This block is also showing the "318-3" casting number on the side. Any one have any info on these blocks? Is the 318-3 designation significant in the newer engines?

I just picked it up last night, so I haven't had time to even get the full casting number, but the -3 stuck out when I was loading the engine up...

TIA

-Alan
 
The "3" means it is 3 times better than a regular 318....Just kidding! Not sure what it means but weren't all 318 engines built with forged cranks? You should post the entire number when you get a chance, someone will know what it is!
 
Yeah, I'm going to the shop tonight to get it up on the stand..I'll have the numbers later tonight.

I thought that many of the 318's were forged, but according to the Mopar Engine book, only the 67's were forged...But then again, it says the 318-3 truck engines had forged AND hardened cranks in them....who knows??

Maybe I'll pull the pan off of it tonight too...
 
The 318 truck crank is what I have in my 340 and it was forged and hardened.
I won't have a broken crank issue in my car anymore.....classic case of PO's mechanic put a neutral balanced converter on a cast crank 340. Broke the snout off right in the middle of the 1st main bearing.
 
Generally -3 motors were truck/industrial/marine engines. Many had the same heavy duty goodies inside as the hi-po engines of the same year. That being said, I think the forged 3.31 stroke cranks were all used up by 73 (even the 340 went to cast).

There should be a VIN stanped on the pan rail to confirm what it was in originally.

Also, the -3 designation should be stamped in on the left front as well.
 
318's are cast crank internal balance except 67 truck, along with the steel 273 cranks they put #324 57cc closed chamber heads to bump the comp.
These heads flow water through the cross over and if used on different blocks must be blocked off otherwise hydro lock city.
 
You must log in or register to reply here.
-

Back
Top