Forged Crankshaft Chrysler GEN III Hemi 3.900 Stroke 345-3900JB6F By Molnar

Need a crankshaft that won’t flinch under pressure? Molnar’s got your back—and your bottom end—with this Standard Weight 3.900″ Stroke Crankshaft for Chrysler Gen III HEMI engines. It’s forged from premium 4340 steel, which is basically the superhero alloy of engine internals. (Think of it as the Captain America of crankshafts, minus the spandex.)

This crankshaft is internally balanced, so it plays nice with your rotating assembly without needing a bunch of external counterweights or voodoo. With 2.559″ main journals and 2.100″ rod journals, it’s built to tight specs for excellent fitment and performance. Oh, and it uses a 2-piece rear main seal, just like the classics.

At 3.900″ stroke, this crank is perfect for those looking to build a reliable street bruiser or weekend strip warrior. It’s Molnar’s standard weight series, which means you’re getting a great blend of strength and rotating mass—not too heavy, not too light, but juuust right. Goldilocks would approve (if she were into high-performance HEMIs instead of porridge).

Whether you’re building a naturally aspirated beast or prepping for boost-ville, this crankshaft won’t let you down. It’s tough, precise, and ready for whatever power levels you throw at it—as long as you treat it right and maybe whisper a few kind words during assembly.

So go ahead—give your HEMI the strong, steel spine it deserves. Your pistons will thank you. Your rods will write poetry about it. And your tires? Well… they’ll hate you.