Building a 440 engine. Need a stock stroke crankshaft. Aiming for 580 plus hp. Of all the aftermarket cranks (Molnar, Scat, Eagle, K1), which is the better quality? There are others but those are the ones I’m familiar with.

Stock cubes or a stroker? If stock a factory forged crank is more than up to the task.

Read the OP that you copied.

Sometimes reading is fundamental ...

OP , unless you are starting with a cast crank engine you don't need an aftermarket crank for that HP level. But if you want Aftermarket all of them will be fine , assuming they all have a stock stroke crank.

I'm a big fan of the Molnar quality if you are bent on having aftermarket.

Thanks everyone. My thinking was these forged cranks are 50 plus years old with unknown prior use. It will be leaned on from time to time at the track. Did not want the possibility of metal fatigue in a high stressed part to be a weak link.

I would check with the machine shop your going to use to balance it uses (pricing and availibility). All brands will be up to the task. Including both stock versions.

Well, I’ve got a whole rack of stock cranks with maybe 75,000 miles or less in the ten or so years they were on the road. They were pulled out, inspected, geased up and hung in a crank rack for the past 40 years. I can’t see much metal fatigue there in the rack. Clean them up, mag them and build them in my books for a build like yours. There are still some good stock and std cranks out there to be found. I’ve bought 3 in the last several months. So and old proven crank vs a Chinese guy behind a machine? I’ll take my chances with the old for the money. I’ve bought a Molnar from a stroker build. I’ll be assembling it soon. Looks to be a nice piece. I used one Eagle crank. It is still working.

I have been flogging my 600+ hp 440 with a stock steel crank since the 90's

If looking to spend money, quality rods and lighter pistons is where I'd plunk down money though the stock rods once prepped with good bolts are very stout. Mine have seen a few trips to 7000 rpm

I wouldn't bother w/ an aftermarket crank for this type of build. A stock forged crank will handle it.

Agree stock crank thats decent is enough If you want a new crank go stroker.Nows the time if you spend the $$$.My 440 stock crank turns 6500 all the time and has been in since I built it in 99