Any info on this crankshaft 2550008

[434nova]

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
Thanks

 

[jckcolarusso]

3.590

 

[forcefed3.8's]

All BMS cranks have the same part number as a raw forging. Its all in the finish machine work. There were also 5150, 4140, and 4340 versions.

 

[rag231]

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.

 

[TurboWh1]

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

 

[rag231]

Both of mine have T96 embossed on them.