Eagle Forged Stroker Crank CRACKED

pettybludart said

Last winter while doing a refresh on my 410 stoker build,my builder magnafluxed my forged Eagle crank.This is the crack he found.I was lucky to have caught this before catastrophic failure.I replaced the crank with a forged Molnar crank.You can really tell the difference in quality by just comparing.Oh I,ve also been running an ATI Super dampner for 12 year without issue.Molnar crank on right

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When you look at the overlap of the rod and main journals on the stroker cranks, there is not a lot of metal there. Also the Eagle crank is saving weight and metal in the web area. The white marker appears to be following the oil hole drilling from the outlet. Appears to be a substandard crank. The Molnar crank tapers nicely from the main journal area to the outside of the rod journal. This helps reduce the possibility of unwanted flexing which will lead to stress cracking. That Eagle crank was born with C4 in it.
David Vizard has a video that he discuses C/S balancing for power and mentions companies he has not had problems with. Scat and Molnar are on the list. The Scat 9000 series he recommends for quality and affordability. A good video to watch.
I noticed the Molnar crank is aero contoured with the cut angle throwing displaced oil toward the main webbing to slid down the web and into the oil pan. This gets the oil out of the air around the rotating assembly where it resists the motion of the components.