Any info on this crankshaft 2550008


Active Member
My buddy picked up a stage 2 engine and it has this crankshaft in it. Any info on what stroke it could be from the casting# 25500008


Well-Known Member
For a BMS crank it really depends on the race series that the engine was designed for. 2.66 ( which I have never held before) all the way up to 3.625. In a stage 2 motor the 2 most common sizes found were 3.59 and 3.625 to put you in the 274cu inch ballpark. The 3.59 motors had the 4.020 bore. Do a quick measure on your bore or look for more numbers hand stamped on the crank. I still have 2 raw BMS forgings that can be machined down.


Well-Known Member
The BMS cranks are stamped to help you identify which material the crankshaft is. Here is a confirmed 4340 example via x-ray machine.


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