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OS Giken Mazda FC3S RX7 NA (MT Only) / Miata NA8/NB8 (MT Only) Super Lock LSD OS Giken OSGMZ072-HA
OS Giken Mazda FC3S RX7 NA (MT Only) / Miata NA8/NB8 (MT Only) Super Lock LSD OS Giken OSGMZ072-HA
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OS Giken Mazda FC3S RX7 NA (MT Only) / Miata NA8/NB8 (MT Only) Super Lock LSD

OS Giken
OSGMZ072-HA
Differentials
Out of stock
$ 1,450.00

SKU: MZ072-HA

OS Giken Mazda FC3S RX7 NA (MT Only) / Miata NA8/NB8 (MT Only) Super Lock LSD

The OS Giken MZ072-HA Super Lock LSD is a helical gear limited slip differential built for Mazda FC3S RX-7 NA manual transmission models from 1986 to 1991 and Miata NA8 from 1994 to 1997 plus NB8 from 1999 to 2000 manual transmissions. This 2-way LSD locks both wheels instantly under acceleration and deceleration for sharper cornering and faster lap times. Its clutchless design ensures reliable performance without adjustments or rebuilds.

Key Features

  • Helical Gear Mechanism: Delivers smooth progressive traction control without clutch plates that wear out over time.
  • Torque Bias Ratio: Starts at 3:1 initial and reaches 6:1 maximum for balanced power delivery to both rear wheels.
  • WPC Gear Treatment: Boosts gear surface strength by 30 percent while cutting friction and rotational inertia for quicker response.
  • 4340 Alloy Steel Gears: Forged side and pinion gears handle high torque loads from track days and spirited drives.
  • Lightweight Design: Reduces unsprung weight compared to stock diffs for improved handling and suspension feel.

Product Notes

  • Manual transmission models only. not compatible with automatics.
  • Requires LSD-specific gear oil like 75W-85 GL-5 full synthetic for optimal operation.
  • Arrives fully assembled ready for installation.

Installation Notes

  • Professional installation recommended.
  • Bolt-in replacement for factory open differential. matches OEM mounting points.
  • Compatible with stock ring and pinion ratios or aftermarket setups.

This Part Fits

Year Make Model Submodel
1986-1991 Mazda RX-7 FC3S NA (MT)
1979-1985 Mazda RX-7 S, GS, GSL, GSL-SE
1983 Mazda RX-7 Limited Edition
1990-1997 Mazda Miata Base, SE, M Edition
1993-1997 Mazda Miata LE, STO
1999-2005 Mazda Miata Base, 10th Anniversary, LS, SE, Shinsen

Why Choose OS Giken?

  • Racing pedigree from D1GP drift series and Super GT championships.
  • Hand-assembled in Japan with tight tolerances for consistent operation.
  • Engineered to endure repeated hard launches and high-speed corners.

Frequently Asked Questions

  • Q: Will this fit manual transmission Miata NA8 and NB8 models?
    A: Yes, direct fit for 1994-1997 NA8 and 1999-2000 NB8 with 5-speed manual. confirms traction upgrade for rear-wheel drive setups.
  • Q: What materials and treatments are used on the gears?
    A: Forged 4340 chromoly steel with WPC micro-peening for fatigue resistance and smooth engagement.
  • Q: What warranty covers this LSD and any install tips?
    A: Backed by 1-year manufacturer warranty against defects. Use a lift and torque specs from service manual during install.

Shipping & Handling

  • Method: UPS Ground / FedEx Ground
  • Availability: In stock - ships same or next business day
  • Packaging: Heavy-duty box measuring 20in x 16in x 12in
  • Weight: 42 lbs

Request For Information

Have questions about OS Giken Mazda FC3S RX7 NA (MT Only) / Miata NA8/NB8 (MT Only) Super Lock LSD? Fill out the form below and we'll get back to you by the next business day.
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Black Ops Auto Works proudly honors active duty military, veterans, National Guard, reserves, police officers, firefighters, and EMTs with an exclusive 5% discount on all performance parts and carbon fiber upgrades. Verify instantly and start saving today.

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