Eagle 4340 Forged Crankshaft, 4.250" Stroke, 3.25" main, 421/428/455 Block, 2.200" BBC RJ

CRANKSHAFTS

 

Cast crankshafts are an excellent alternative to O.E. Cranks. These crankshafts are new cast pieces made with modern material and casting processes to be a great alternative to 30 year old factory cranks. Recommended for use in street engines without power adders. Many factory cranks we check have stress cracks, so even though your crank has not broken yet, you may have a problem developing that could destroy your engine.

 

Forged Cranks offer a tremendous advantage in strength and durability over cast cranks. This is very inexpensive insurance to protect your engine and even if its not needed at your current horsepower level now. Upgrading to a forged crank to build a solid bottom end will give you the option to safely upgrade performance and increase horsepower without having to worry about costly breakdowns in the future.

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ESP ARMOR

ESP Armor is a revolutionary new surface finishing process that is available only through Eagle. Similar processes exist, but ESP armor is unique because it is NOT A COATING, nor is it a chemical etching process. ESP Armor is a unique surface finishing process that results in an incredibly slick surface. This has many benefits. First and foremost is reduce bearing friction. By giving the oil a slicker surface to slide along, the bearing friction is reduced. This will also be evident in slower oil heating, reduced windage losses, and improved corrosion resistance. You will also notice that your bearings will live longer as a result of ESP Armor. The finish is unmistakable. Although it resembles chrome, it is not a coating that might flake off or wear out. Eagle is so confident in the effects ESP Armor has on our rods and cranks that we include a ONE YEAR LIMITED WARRANTY against breakage when ESP Armor is used on any 4340 steel crankshaft or H-beam rod. Many customers have tried it and all have been not only pleased, but surprised by the results. You’ve got to see it, and use it, to believe it!

 

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The Butler Process

All rotating assemblies sold by Butler Performance, regardless of brand, are balanced in our shop by our experienced machinists.

We don't take anyone else's word when it comes to the parts we stand behind. We put all rotating assemblies through the Butler Process for quality and performance. Our internal balancing process ensures each part of the kit is put through a multi-step inspection process. We then weigh and pin fit the rods and pistons as needed. We computer balance the crankshaft to the rest of the assembly. This process ensures that all the parts of the assembly are matched to form a "Butler Performance" worthy assembly. We then document all weights and information on a balance card that ships with the assembly.

We also offer sevices to balance crankshafts to your Bob Weight.

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We sell cast cranks from Eagle, RPM, and Ohio Crankshaft. These crankshafts are new cast pieces made with modern material and casting processes to be a great alternative to 30 year old factory cranks. Many factory cranks we check have stress cracks, so even though your crank has not broken yet, you may have a problem developing that could destroy your engine.