440 piston rod qustion

[73charger440]

ok here goes i have two 440 blocks one had a cast crank  and the other one had a forge crank,  my question is both the cast and forge crank motors both have the same model # on the  piston rods i think its a 185# i looked it up in my book and it said  they where high perf rods ,but it also said there a internal (forge)
external(cast) balenced moters so  do the rods from the cast engine weight the same as the engine with the forge ,and would the rods off the cast crank work with the forge cank they are in a little better shape ,im planning on shit cannning the pistons so thats not a factor .thanksl

[TylerCharger69]

I believe they are the same....What they are referring to is the crankshaft itself as far as internal and external balanced is concerned.  But the journal sizes are the same.   If I'm wrong...someone please chime in on this one

[John_Kunkel]

The 440 rod with the forging number 1851535 is the standard rod used from '66 up to the end of production. These are often referred to as "LY" rods and were used in many other RB engines.

The heavy rods (often called 6-pack rods) have the forging number 2951908.

[TylerCharger69]

Cool!!!   I happen to have the six-pack rods!!!

[Cooter]

Note: "SIX -PACK" rods are heavier than the pass. car "LY" rods and not suited for any kinda of high RPM use...I wouldn't go swapping Cast Crank Rods into a Steel crank engine without first rebalancing the bottom end myself...

[73charger440]

so the forge crank and the cast crank rods that have the same model # are the same

[flyinlow]

Years ago the "six pack rods" where the hot item. They are wider and heavier. I had them in a 1972 steel crank 440 Hp I built  ( cop car engine) They worked fine.

The last 440 I built started as a 1977 Chrysler station wagon motor. Cast crank, LY rods. I reused the rods. Low milage engine operated at low rpms.

Used a stock steel crank , LY rods ,arp bolts, SRP lightweight forged pistons.

My machine shop manager  said  The LY rods where a good choice for a 500 HP street engine. Their  lighter weight compaired to the sixpack rods combined with the lighter SRP  pistons would reduce bearing loads. He strongly sugested balancing the rotating group. I did.