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Powermaster 12si Style GM Alternators


Powermaster
Powermaster 12si Style GM Alternators

Product images may differ from actual product appearance.

GM has offered several series of alternators over the years, each time taking a step up in performance. The great thing about these alternators and aftermarket brackets is that for the most part they are interchangeable. Starting with the externally regulated 10dn alternator of the 1960s and moving all the way to the CS130D alternator of late, aftermarket brackets with rod end tensioners will interchange. The 2" mounting foot width is common to all of them and the 6.61" bolt spacing is common (except the CS130D has 7.24" bolt spacing, which many brackets accommodate). Made in the USA.

12si Alternators
100A Specifications
70A @ 2,400 RPM @ 13.2 VDC @ 77F
Operating Range: -40C to 150C
Maximum RPM: 18,000

140A Specifications
80A @ 2,400 RPM @ 13.2 VDC @ 77F
Operating Range: -40C to 150C
Maximum RPM: 18,000

Smooth Look Alternators
  • The Ultimate Custom Billet look at affordable prices
  • Smooth die cast housing with teardrop design
  • One or three wire
  • Available in 100 and 140 amp output
  • Custom HV (high volume) fan - optional
  • Largest selection of fans, pulleys, nose cones, and baffle plates in the industry
  • Smooth back with special Powermaster vents for pull through cooling
  • Gold battery post
  • Available in 4 finishes
  • Proof-of-Performance Tag


    12si Race-Prepped Alternators
    80A Specifications
    70A @ 2,400 RPM @ 13.2 VDC @ 77F
    Operating Range: -40C to 150C
    Maximum RPM: 18,000

    100A Specifications
    80A @ 2,400 RPM @ 13.2 VDC @ 77F
    Operating Range: -40C to 150C
    Maximum RPM: 18,000
  • One or three wire operation
  • Complete w/fan & V-belt pulley
  • Gold battery post
  • 70 AMPS at idle for 100A Alternator
  • Recommended charge wire size: 8 AWG
  • Proof-of-Performance Tag


    Alternator Plug Type

    JEGS Easy Kits are designed by JEGS Professionals to help you get all the performance parts you need.



  • 67 Products Page: 1 2 3 ... |  Next Results per Page:
    100 Amp, V-Belt Pulley

    713-17294
    GM 12si-Style Alternator
  • 100 Amp
  • 1v Belt Pulley
  • Chrome
    More info on Powermaster 17294

    Fits Applications
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  • $147.99
    Ships

    713-17294K
    100 Amp Alternator Kit w/Long Water Pump
  • Small Block Chevy
    Includes:
  • Powermaster GM 12si-Style Alternator
  • JEGS High-Output Alternator Wiring Kit
  • JEGS Billet Alternator Mounting Bracket
    More info on Powermaster 17294K
    • FREE
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    Easy Kits
  • $254.99
    Ships

    713-27294
    GM 12si-Style Alternator
  • 100 Amp
  • 1v Belt Pulley
  • Polished
    More info on Powermaster 27294

    Fits Applications
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  • $147.99
    Order Today Ships in 24hrs

    713-7294
    GM 12si-Style Alternator
  • 100 Amp
  • 1v Belt Pulley
  • Natural
    More info on Powermaster 7294

    Fits Applications
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  • $124.99
    Order Today Ships 04/23/14

    713-17297
    GM 12si-Style Alternator
  • 100 Amp
  • 1v Belt Pulley
  • Chrome "Smooth Look"
    More info on Powermaster 17297

    Fits Applications
    • FREE
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      & HANDLING!
  • $149.99
    Order Today Ships 04/23/14

    713-27297
    GM 12si-Style Alternator
  • 100 Amp
  • 1v Belt Pulley
  • Polished "Smooth Look"
    More info on Powermaster 27297

    Fits Applications
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  • $149.99
    Ships

    713-17297-344
    GM 12si-Style Alternator
  • 100 Amp
  • 1v Belt Pulley
  • Includes: Baffle
  • Chrome "Smooth Look"
    More info on Powermaster 17297-344

    Fits Applications
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  • $162.99
    Order Today Ships 04/23/14

    713-27297-344
    GM 12si-Style Alternator
  • 100 Amp
  • 1v Belt Pulley
  • Includes: Baffle
  • Polished "Smooth Look"
    View this item
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  • $162.99
    Order Today Ships 04/23/14

    713-17294-361
    GM 12si-Style Alternator
  • 100 Amp
  • 1v Belt Pulley
  • Includes: Baffle & Cone
  • Chrome
    More info on Powermaster 17294-361

    Fits Applications
    • FREE
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      & HANDLING!
  • $189.99
    Order Today Ships 04/23/14

    713-27294-361
    GM 12si-Style Alternator
  • 100 Amp
  • 1v Belt Pulley
  • Includes: Baffle & Cone
  • Polished
    More info on Powermaster 27294-361

    Fits Applications
    • FREE
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      & HANDLING!
  • $159.99
    Ships

    713-7295
    GM 12si-Style Alternator
  • 100 Amp
  • 1v Belt Pulley
  • Includes: Custom HV Fan
  • Natural "Smooth Look"
    More info on Powermaster 7295

    Fits Applications
    • FREE
    • SHIPPING
      & HANDLING!
  • $147.99
    Order Today Ships 04/23/14

    713-17295
    GM 12si-Style Alternator
  • 100 Amp
  • 1v Belt Pulley
  • Includes: Custom HV Fan & Cone
  • Chrome "Smooth Look"
    More info on Powermaster 17295

    Fits Applications
    • FREE
    • SHIPPING
      & HANDLING!
  • $192.99
    Ships

    713-27295
    GM 12si-Style Alternator
  • 100 Amp
  • 1v Belt Pulley
  • Includes: Custom HV Fan & Cone
  • Polished "Smooth Look"
    More info on Powermaster 27295

    Fits Applications
    • FREE
    • SHIPPING
      & HANDLING!
  • $192.99
    Order Today Ships 04/23/14

    713-27295-303
    GM 12si-Style Alternator
  • 100 Amp
  • 1v Belt Pulley
  • Includes: Custom HV Fan & 6-Hole Cone
  • Polished "Smooth Look"
    More info on Powermaster 27295-303

    Fits Applications
    • FREE
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      & HANDLING!
  • $197.99
    Order Today Ships 04/23/14

    713-17295-361
    GM Delco-Style Alternator
  • 100 Amp
  • 1v Belt Pulley
  • Includes: Baffle & Cone
  • Chrome "Smooth Look"
    View this item
    • FREE
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  • $171.99
    Ships

    713-27295-361
    GM 12si-Style Alternator
  • 100 Amp
  • 1v Belt Pulley
  • Includes: Baffle & Cone
  • Polished "Smooth Look"
    View this item
    • FREE
    • SHIPPING
      & HANDLING!
  • $171.99
    Order Today Ships 04/23/14
    100 Amp, Serpentine Pulley

    713-17294-114
    GM 12si-Style Alternator
  • 100 Amp
  • 6-Groove Serpentine Pulley
  • Chrome
    More info on Powermaster 17294-114

    Fits Applications
    • FREE
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      & HANDLING!
  • $155.99
    Ships

    713-27294-114
    GM 12si-Style Alternator
  • 100 Amp
  • 6-Groove Serpentine Pulley
  • Polished
    More info on Powermaster 27294-114

    Fits Applications
    • FREE
    • SHIPPING
      & HANDLING!
  • $155.99
    Order Today Ships 04/23/14

    713-17297-114
    GM 12si-Style Alternator
  • 100 Amp
  • 6-Groove Serpentine Pulley
  • Chrome "Smooth Look"
    More info on Powermaster 17297-114

    Fits Applications
    • FREE
    • SHIPPING
      & HANDLING!
  • $153.99
    Ships

    713-27297-114
    GM 12si-Style Alternator
  • 100 Amp
  • 6-Groove Serpentine Pulley
  • Polished "Smooth Look"
    More info on Powermaster 27297-114

    Fits Applications
    • FREE
    • SHIPPING
      & HANDLING!
  • $153.99
    Order Today Ships 04/23/14

    713-17297-364
    GM 12si-Style Alternator
  • 100 Amp
  • 6-Groove Serpentine Pulley
  • Includes: Baffle
  • Chrome "Smooth Look"
    More info on Powermaster 17297-364

    Fits Applications
    • FREE
    • SHIPPING
      & HANDLING!
  • $169.99
    Order Today Ships 04/23/14

    713-27297-364
    GM 12si-Style Alternator
  • 100 Amp
  • 6-Groove Serpentine Pulley
  • Includes: Baffle
  • Polished "Smooth Look"
    View this item
    • FREE
    • SHIPPING
      & HANDLING!
  • $169.99
    Order Today Ships 04/23/14

    713-7296
    GM 12si-Style Alternator
  • 100 Amp
  • 6-Groove Serpentine Pulley
  • Includes: Custom HV Fan
  • Natural "Smooth Look"
    More info on Powermaster 7296

    Fits Applications
    • FREE
    • SHIPPING
      & HANDLING!
  • $153.99
    Order Today Ships 04/23/14

    713-17296
    GM 12si-Style Alternator
  • 100 Amp
  • 6-Groove Serpentine Pulley
  • Includes: Custom HV Fan & Cone
  • Chrome "Smooth Look"
    More info on Powermaster 17296

    Fits Applications
    • FREE
    • SHIPPING
      & HANDLING!
  • $199.99
    Order Today Ships in 24hrs

    713-27296
    GM 12si-Style Alternator
  • 100 Amp
  • 6-Groove Serpentine Pulley
  • Includes: Custom HV Fan & Cone
  • Polished "Smooth Look"
    More info on Powermaster 27296

    Fits Applications
    • FREE
    • SHIPPING
      & HANDLING!
  • $199.99
    Order Today Ships 04/23/14
      713-17296-311
    GM 12si-Style Alternator
  • 100 Amp
  • 6-Groove Serpentine Pulley
  • Includes: Custom HV Fan & 6-Hole Cone
  • Chrome "Smooth Look"
    View this item
    • FREE
    • SHIPPING
      & HANDLING!
  • $224.99
    Order Today Ships 04/23/14
      713-27296-311
    GM 12si-Style Alternator
  • 100 Amp
  • 6-Groove Serpentine Pulley
  • Includes: Custom HV Fan & 6-Hole Cone
  • Polished "Smooth Look"
    View this item
    • FREE
    • SHIPPING
      & HANDLING!
  • $224.99
    Order Today Ships 04/23/14

    713-17296-313
    GM 12si-Style Alternator
  • 100 Amp
  • 6-Groove Serpentine Pulley
  • Includes: 6-Hole Cone
  • Chrome "Smooth Look"
    More info on Powermaster 17296-313

    Fits Applications
    • FREE
    • SHIPPING
      & HANDLING!
  • $224.99
    Order Today Ships 04/23/14
      713-27296-313
    GM 12si-Style Alternator
  • 100 Amp
  • 6-Groove Serpentine Pulley
  • Includes: 6-Hole Cone
  • Polished "Smooth Look"
    View this item
    • FREE
    • SHIPPING
      & HANDLING!
  • $224.99
    Order Today Ships 04/23/14
      713-17296-361
    GM 12si-Style Alternator
  • 100 Amp
  • 6-Groove Serpentine Pulley
  • Includes: Baffle & Cone
  • Chrome "Smooth Look"
    View this item
    • FREE
    • SHIPPING
      & HANDLING!
  • $179.99
    Order Today Ships 04/23/14

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