This is a GN1Performance "STOCK STROKE STEEL CRANK 3.400 " for a 1986 or 1987 Buick Grand National, T Type, Turbo T, or GNX 3.8 liter turbo V6.

KEEP IN MIND THIS IS A 4340 CRANK SHAFT, NOT 4140. THIS 4340 MATERIAL WILL SUPPORT 1000-1200 HP EASILY.  

*In some cases, crank shafts may require minor machine work.