Crankshaft, 74mm, Forged Chromoly, 8 Dowel, VW Journals

OVERVIEW

The crankshaft is the absolute heart of your air-cooled engine, and when you are building for performance, you cannot afford to settle for a cast factory unit. This EMPI 74mm forged 4140 chromoly crankshaft is engineered to provide the ultimate foundation for a high-revving, high-torque stroker engine. By increasing the stroke to 74mm, you gain significant displacement and "grunt" without the extreme clearancing issues often associated with 82mm or 84mm cranks. This makes it the "sweet spot" for street performance builds and rugged off-road machines alike. The integrated counterweights are a critical upgrade over stock, as they drastically reduce power-robbing crank-flex and damaging high-RPM harmonics that can lead to premature bearing wear and engine case fatigue. When you are spinning your Flat-Four to the limit, this crank ensures that your rotating assembly stays stable and smooth throughout the entire power band.

Crafted from premium 4140 chromoly steel, this crankshaft undergoes a rigorous manufacturing process to ensure it can withstand the rigors of performance driving. It is precision ground, micro-polished, and then nitrided to create an incredibly hard surface finish that resists wear and friction. The oiling system has been optimized with cross-drilled passages and chamfered oil holes, ensuring that your rod bearings receive a constant, high-pressure supply of lubricant even under extreme lateral loads or high-heat conditions. Featuring a true 8-dowel configuration, this crank provides a rock-solid interface for your flywheel, preventing the dreaded "shearing" of dowel pins that often occurs in high-horsepower applications. Whether you are building a weekend cruiser, a Baja-ready Beetle, or a vintage-style racer, this 74mm forged crank from Appletree Auto delivers the reliability and performance you demand.

FITMENT

This crankshaft is designed for Type 1 based air-cooled Volkswagen engines. Please note that stroker crankshafts require specific clearancing and matching components.

• Volkswagen Beetle: 1954 through 1977 (Standard and Super Beetle)
• Volkswagen Karmann Ghia: 1956 through 1974
• Volkswagen Bus / Transporter: 1954 through 1971 (Type 1 Engine styles)
• Volkswagen Thing / Type 181: 1973 through 1974
• Volkswagen Type 3 (Squareback, Fastback, Notchback): 1961 through 1973
• Custom Applications: Dune Buggies, Sand Rails, Baja Bugs, and Trikes utilizing Type 1 engine cases.

SPECS

• Stroke: 74mm (Stroker)
• Material: Forged 4140 Chromoly Steel
• Journal Type: Standard VW Rod Journals
• Main Journals: Standard VW Mains
• Flywheel Attachment: 8-Dowel Pattern (Requires 8-dowel flywheel)
• Dowel Pin Size: 8mm
• Oiling: Cross-drilled and chamfered oil holes for superior lubrication
• Finish: Nitrided and micro-polished journals
• Balance: Precision ground and counter-weighted
• Weight: Approximately 24.6 lbs

PRO TIPS

1. Check Your Internal Clearances

Even though a 74mm stroke is more "case-friendly" than larger strokers, you MUST still perform a dry-fit of the rotating assembly. Check for interference between the connecting rod bolts and the engine case webs, as well as the camshaft lobes. In many cases, minor "clearancing" or grinding of the engine case is required to ensure the rods have at least .040"" to .060"" of clearance. Don''t forget to check the clearance between the piston skirts and the crankshaft counterweights at Bottom Dead Center (BDC).

2. Always Balance the Full Assembly

While this EMPI crankshaft is precision manufactured, for the longest engine life and smoothest operation, you should have the entire rotating assembly balanced together by a professional machine shop. This includes the crankshaft, the 8-dowel flywheel, the pressure plate, the front pulley, and your matched sets of rods and pistons. Balancing the assembly as a single unit eliminates vibrations that can destroy main bearings and cause the engine case to "shuffle" or pound out the center main bearing saddle.

3. Use High-Quality 8-Dowel Components

Since this crankshaft features an 8-dowel interface, you must use a high-quality 8-dowel forged flywheel. When installing the flywheel, ensure you are using a heavy-duty chromoly gland nut and torque it to the manufacturer''s specifications (typically 275-350 ft-lbs depending on the hardware). Using an inferior gland nut or failing to reach the proper torque can result in the flywheel loosening, which will quickly ruin both the crankshaft and the flywheel. Don''t forget to use a high-pressure assembly lube on the journals during final assembly to prevent dry-start wear.