Cam Plug, with Groove, for Type 1 VW Engines

OVERVIEW

When you are deep into a performance engine build or a meticulous stock restoration, it is the smallest components that often dictate the long-term reliability of your air-cooled powerplant. The EMPI Cam Plug with Groove is a critical sealing element designed specifically for Type 1 based engine cases that feature the machined recess for a positive-lock fit. Unlike early-style flat plugs that relied solely on friction and sealant, this grooved version is engineered to seat firmly into the engine case halves, providing a mechanical barrier against oil pressure. Reusing an old, distorted cam plug is one of the most common mistakes a novice builder can make, often resulting in a frustrating "mystery leak" at the rear of the engine that requires pulling the entire unit to fix. By installing a fresh, high-quality steel plug, you ensure that your camshaft bore remains hermetically sealed, keeping your oil where it belongsinside the gallery lubricating your valvetrain.

Precision is everything when it comes to the magnesium or aluminum alloys used in Volkswagen engine cases. This cam plug is manufactured to exact tolerances to match the factory 113-101-157C specifications, ensuring that it does not create undue stress on the case webs while still maintaining a tight, leak-proof interface. Whether you are running a high-revving 2110cc stroker or a reliable 1600cc dual-port, the pressure fluctuations inside the crankcase can be significant. This grooved plug is specifically designed to handle those internal pressures without "walking" or vibrating loose. At Appletree Auto, we know that your time is valuable, and there is nothing worse than finishing a beautiful build only to see oil dripping from the bellhousing area. This EMPI cam plug provides the professional-grade security you need for a "once-and-done" engine assembly, making it an absolute mandatory purchase for any bottom-end overhaul.

FITMENT

This grooved cam plug is designed for Volkswagen Type 1 based engine cases (1300cc to 2000cc+) that are machined for the grooved-style plug. VW Beetle: 1966-1977 (Standard & Super Beetle) VW Karmann Ghia: 1966-1974 VW Bus / Type 2: 1963-1971 (1500cc & 1600cc engines) VW Type 3 (Squareback, Fastback, Notchback): 1964-1973 VW Thing: 1973-1974 Aftermarket Cases: Fits most modern AS41 and AS21 replacement cases (including EMPI, AutoLinea, and CB Performance).

SPECS

• Part Number: 113-101-157C / 113-507-157C
• Material: Heavy-duty stamped steel
• Design: Grooved / Recessed outer perimeter for mechanical locking
• Compatibility: All 1300cc, 1500cc, and 1600cc based Type 1 engine cases with grooved machining
• Finish: Corrosion-resistant coating for long-term durability
• Quantity: Sold individually (one required per engine)
• Installation Type: Captured between engine case halves during assembly

PRO TIPS

Pro Tip 1: Confirm Your Case Style Before Assembly. It is absolutely vital to verify whether your engine case is machined for a grooved plug or a flat plug before you begin the assembly process. If you attempt to install this grooved plug into an early "flat" case, the case halves will not close properly, and you risk cracking the expensive magnesium casting. Conversely, using a flat plug in a grooved case will lead to an immediate and severe oil leak. Always dry-fit the plug into one side of the case to ensure the groove aligns perfectly with the case''s machined ridge.

Pro Tip 2: Use the Right Sealant Strategy. While the groove provides a mechanical lock, you still need a high-quality non-hardening sealant to ensure a liquid-tight bond. Master builders recommend a very thin smear of Curil T or a similar high-temp case sealant around the perimeter of the plug. Be careful not to use excessive RTV silicone, as "worms" of excess silicone can break off inside the engine and clog oil galleries. The goal is a light, consistent film that fills the microscopic imperfections between the steel plug and the case metal.

Pro Tip 3: Orientation and Seating During Case Closure. When you are ready to mate the two case halves, ensure the cam plug is perfectly vertical and fully seated in the groove of the "down" side of the case. As you lower the second case half into position, double-check that the ridge in the upper half is dropping directly into the plug''s groove. If the case doesn''t close with light hand pressure, stop immediately and check the cam plug alignment. Forcing the case studs tight when the cam plug is slightly misaligned is a guaranteed way to warp the plug or damage the case bore.