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downer
Member
- Joined
- Jul 20, 2014
- Messages
- 107
- Reaction score
- 4
- Points
- 18
- Vehicle Year
- 97 4.0 OHV 4x4
- Engine Type
- 4.0 V6
- Transmission
- Automatic
- 2WD / 4WD
- 4WD
In a search for better than stock pistons, I stumbled upon Subaru WRX STI pistons.
Stock 4.0 specs: Please correct me if these are wrong.
Bore 3.94 (100)
Stroke 3.30 (84)
Rod 5.748 (146)
Comp Height 1.44 (36.6)
Pin Diameter .945 (24)
WRX STI specs:
Bore 3.94 (100) oversized
Stroke 3.11 (79)
Rod length ??
Comp Height 1.21 (30.7)
Pin Diameter .906 (23)
Hemi 5.7L 394-396
Bore 3.937 (100)
Stroke 4.050 (102.9)
Rod 6.125 (156)
Comp Height 1.095 (27.8)
Pin Diameter .927 (23.5)
Are these even possible piston options given the info above? If so, can the pin bore be opened up to .945? Should a decent machine shop be able to do this? Should the pin bore be opened up? I don't have skirt lengths or pin offsets, but it did interest me.
Stock 4.0 specs: Please correct me if these are wrong.
Bore 3.94 (100)
Stroke 3.30 (84)
Rod 5.748 (146)
Comp Height 1.44 (36.6)
Pin Diameter .945 (24)
WRX STI specs:
Bore 3.94 (100) oversized
Stroke 3.11 (79)
Rod length ??
Comp Height 1.21 (30.7)
Pin Diameter .906 (23)
Hemi 5.7L 394-396
Bore 3.937 (100)
Stroke 4.050 (102.9)
Rod 6.125 (156)
Comp Height 1.095 (27.8)
Pin Diameter .927 (23.5)
Are these even possible piston options given the info above? If so, can the pin bore be opened up to .945? Should a decent machine shop be able to do this? Should the pin bore be opened up? I don't have skirt lengths or pin offsets, but it did interest me.
