ARP 206-5401 main stud kit for BMC A-Series engines full set with washers and nuts
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ARP BMC A Series Main Stud Kit

ARP
ARP206-5401
672036008017
Main Stud & Bolt Kits
2 Units In Stock - Ships Next Business Day
$ 42.35
$ 42.35

SKU: 206-5401 | UPC: 672036008017

ARP Pro Series Main Stud Kit for BMC A-Series Engines 1958-1980 Mini Cooper Sprite Midget

The ARP 206-5401 main stud kit upgrades crankshaft retention in all BMC A-Series engines including 948cc 997cc 1098cc 1275cc and 1293cc variants found in Mini Cooper Austin Healey Sprite MG Midget and Morris Minor. These 8740 chrome-moly studs deliver 190,000 psi tensile strength with black oxide finish for precise clamping force and alignment under high-RPM street race and rally loads. Precision-ground and heat-treated with rolled threads this kit replaces factory bolts directly without block modifications.

Key Features

  • 8740 Chrome-Moly Construction: 190,000 psi tensile strength holds crankshaft securely during extreme high-RPM operation
  • Black Oxide Finish: Rolled threads after heat treatment resist fatigue and protect against corrosion
  • Included Hardware: Parallel-ground washers and 12-point nuts distribute load evenly across all five main caps
  • Bolt-In Fitment: Direct replacement for factory main bolts in stock or modified A-Series blocks
  • Complete Kit: 10 studs 10 washers and 10 nuts cover full engine installation needs

Product Notes

  • Fits all BMC A-Series engines 948cc to 1293cc
  • Torque to 65 ft-lbs with ARP Ultra-Torque lube
  • Ships in protective retail box

Installation Notes

  • Professional installation recommended.
  • Use ARP Ultra-Torque lube on threads and under nut faces.
  • Torque in 3 steps to 65 ft-lbs check main bearing clearance after install.

This Part Fits

Year Make Model Submodel
1958-1971 Austin Healey Sprite MKI MKII MKIII MKIV
1961-1979 MG Midget MKI MKII MKIII
1959-2000 Mini Cooper A-Series All
1959-1980 Morris Mini A-Series All
1963-1971 Morris Minor 1000 Series

Why Choose ARP?

  • Over 60 years of championship-winning fastener engineering
  • Trusted by every major race series worldwide
  • Limited lifetime warranty

Frequently Asked Questions

  • Q: Fits 1275cc Cooper S?
    A: Yes fits all BMC A-Series engines 948cc to 1293cc including Cooper S
  • Q: Material and torque spec?
    A: 8740 chrome-moly studs torque to 65 ft-lbs with ARP Ultra-Torque lube
  • Q: Reusable after install?
    A: Yes if undamaged and threads measure within ARP specifications

Shipping & Handling

  • Method: UPS or FedEx Ground
  • Availability: In stock - ships same or next business day
  • Packaging: Protective retail box 8 x 6 x 1.5 inches
  • Weight: 1 lb

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