BUGPACK Forged Flanged Crankshaft | Air-Cooled VW Type 1 | 4340 Nitrided, Chevy Journal (B4-0002)

BUGPACK Forged Flanged Crankshaft — 4340 Nitrided, Chevy Journal

BUGPACK forged flanged crankshaft for high-horsepower air-cooled VW engine builds — forged from 4340 chromoly steel with nitrided Type-IV main journals and Chevy rod journals. The 6-bolt, 6-pin flange eliminates flywheel-to-crank movement that costs power and durability at high RPM. Select your stroke from the dropdown.

Cast cranks fail at high RPM and high load. A forged 4340 chromoly crank, properly nitrided and balanced, is the foundation for any engine making real power. The Chevy journal allows use of a far wider range of high-end aftermarket rods (Carrillo, Eagle, Manley, Scat, etc.) than the OEM VW journal sizes permit — cost-effective compared to building around custom VW-journal rods.

Vehicle Fitment

• Beetle: All years (Type 1)
• Bus: All years
• Karmann Ghia: All years
• Type 3: All years
• Thing: All years

Why Choose BUGPACK?

BUGPACK is EMPI's high-performance engine and chassis line for the air-cooled VW community. The forged crank program targets serious horsepower builds where stock or cast components won't survive.

Key Features & Benefits

• High-horsepower ready: For air-cooled VW engine builds requiring a forged crank
• Chevy rod journals: Builds spec'd for 2.000" small-block Chevy rods
• Type-IV mains: Type-IV main journal compatibility
• Flange mounting: Flange-style flywheel mounting (6-bolt, 6-pin)

Technical Specifications

• Material: 4340 chromoly forged
• Main Journals: Nitrided, Type-IV
• Rod Journals: Chevy (2.000")
• Flywheel Flange: 6-bolt, 6-pin
• Stroke Options: 78mm (B4-0002-5), 82mm (B4-0003-1), 84mm (B4-0002-6)
• Sold As: Each
• Weight: ~24 lb (shipping)

Frequently Asked Questions

• What rod journal size does this crank use? Chevy (2.000" small-block Chevy) rod journals.
• What stroke options are available? 78mm (B4-0002-5), 82mm (B4-0003-1), and 84mm (B4-0002-6, big-stroke option).
• Why choose a forged crank? Cast cranks fail at high RPM and high load; a forged 4340 chromoly crank, properly nitrided and balanced, is the foundation for a high-power build.

Explore Related Categories

Engine Engine Parts All VW Air-Cooled

WARNING: This product can expose you to chemicals known to the State of California to cause cancer and reproductive harm. For more information, go to www.P65Warnings.ca.gov. All parts legal for use on pre-pollution controlled vehicles only.