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Alternator Conversion Bracket, GM 10SI & 12SI, 70-83 240Z-260Z-280Z-280ZX

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Part #:12-4069
Price: $117.97
Updated! The manufacturer of this bracket has added a structural reinforcement to the underside for heavier alternators!

  • (1) GM Alternator Conversion Bracket
  • (1) GM Alternator Lower Mounting Hardware Set

GM alternators have been a go-to for high output alternators for many years; however, they are not a direct fit installation on L-Series engines. Installation used to require modification of the factory cast bracket, which could easily go wrong. This bracket was designed from the ground up to hold GM 10SI and 12SI type alternators to L-Series blocks and was designed with strength in mind. Includes hardware to mount the alternator to the bracket; uses factory hardware to mount to the block.

Image Note:
The images of this bracket not installed show the updated version with the reinforcement, while the installed images show the previous version. There are no changes to the fitment or position between the two versions.

Hardware Notes:
We have seen some variance in the bolt size used by Nissan to hold the factory alternator bracket to the block. You may need to purchase 2 slightly shorter bolts than what your engine has in order to install this bracket, as the base is slightly thinner than the original part. The stud and nut used for the third mounting point should work as is, or, they can be replaced with a bolt if desired. Also keep in mind that GM alternators use SAE hardware, which means the bolt for the alternator arm will also need to be replaced.

Model Guide:
Datsun 240Z, 260Z, 280Z, 280ZX

Code Guide:
Datsun S30, S130

Year Guide:
1970, 1971, 1972, 1973, 1974, 1975, 1976, 1977, 1978, 1979, 1980, 1981, 1982, 1983

Some parts may not fit every version of every year listed. See product Title & Description for any application breakdowns or customization options, and contact us with any questions.

  • 1970 Datsun 240Z
  • 1971 Datsun 240Z
  • 1972 Datsun 240Z
  • 1973 Datsun 240Z
  • 1974 Datsun 260Z
  • 1975 Datsun 280Z
  • 1976 Datsun 280Z
  • 1977 Datsun 280Z
  • 1978 Datsun 280Z
  • 1979 Datsun 280ZX
  • 1980 Datsun 280ZX
  • 1981 Datsun 280ZX
  • 1982 Datsun 280ZX
  • 1983 Datsun 280ZX
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