EMPI GT-7 Camshaft, Large Displacement, High Range Power

OVERVIEW

When it comes to extracting every ounce of high-end performance from your air-cooled powerplant, the EMPI GT-7 Camshaft stands as a pinnacle of engineering for the serious engine builder. Designed specifically for large displacement engines that demand massive airflow at high RPMs, the GT-7 is the ultimate choice for "Hot Street" builds and aggressive Off-Road competition. This isn''t just another camshaft; it is part of EMPI''s legendary GT Series, manufactured from brand-new Chilled Cast Iron billets to exact tolerances. The chilled cast process ensures superior hardness and longevity on the lobe surfaces, which is critical when running the high-tension valve springs required for high-range power delivery. Whether you are screaming through the dunes or looking for that extra edge on the asphalt, the GT-7 delivers a power band that turns heads and wins races.

Installation and reliability are at the forefront of the GT-7''s design. Every GT-7 camshaft is Parkerized, a specialized phosphate coating that provides an essential layer of protection during the critical initial break-in period, preventing premature wear before the oil film is fully established. Furthermore, EMPI has factory-clearanced these cams for stroker cranks, saving you hours of tedious hand-grinding and ensuring that your rotating assembly moves freely even in long-stroke applications. To make your build even smoother, EMPI includes new Grade 8 hardware and premium assembly lube right in the box, along with a detailed cam card for precise timing. To achieve the maximum performance and durability this cam was engineered for, we highly recommend pairing it with a fresh set of EMPI lifters (Part # 21-4300-0) to ensure a perfect wear pattern from the very first turn of the key.

FITMENT

The EMPI GT-7 Camshaft is designed for Type 1 based air-cooled engines, including:

• Volkswagen Beetle: 1946 through 1979 (Sedan and Convertible)
• Volkswagen Karmann Ghia: 1956 through 1974
• Volkswagen Bus / Type 2: 1950 through 1971
• Volkswagen Thing / Type 181: 1973 through 1974
• Volkswagen Squareback / Fastback / Type 3: 1962 through 1973
• Custom Sand Rails and Dune Buggies: Utilizing Type 1 1600cc based engine cases

SPECS

Below are the technical specifications for the EMPI GT-7 Camshaft (Part Number 77-2101-0):

• Application: Large Displacement / High Range Power
• Recommended Rocker Ratio: Designed for 1.4:1 High-Lift Rockers
• Duration: 295 Degrees
• Cam Lift: .430 Inches
• Valve Lift (@ 1.1:1 Rockers): .538 Inches
• Lobe Separation: Optimized for high-RPM scavenging
• Material: New Chilled Cast Iron Billet
• Finish: Parkerized (Phosphate Coated) for break-in protection
• Clearance: Pre-cleared for Stroker Crankshafts
• Included Hardware: Grade 8 Bolts and Assembly Lube
• Recommended Lifters: EMPI Part # 21-4300-0 (Sold Separately)

PRO TIPS

1. Prioritize Proper Break-In Procedure

The first 20 minutes of a new camshaft''s life are its most critical. When installing the EMPI GT-7, never reuse old lifters; always install new EMPI lifters to ensure the surfaces mate correctly. Use a high-quality break-in oil with high ZDDP (Zinc) content. Upon initial startup, immediately bring the engine to 2,0002,500 RPM and maintain that speed for 20 minutes. Do not let the engine idle during this time, as idling does not provide sufficient oil splash to lubricate the cam lobes and lifter faces. This process is essential to "work-harden" the Parkerized surfaces and ensure a long service life for your valvetrain.

2. Verify Valvetrain Geometry and Clearances

Because the GT-7 features a high lift of .430" at the cam, and is intended for use with 1.4:1 rockers, your total valve lift will be significantly higher than a stock setup. It is mandatory to check for "coil bind" (where the valve spring is fully compressed before the cam reaches full lift) and "valve-to-piston" clearance. You must also ensure that the valve retainers do not strike the valve seals or the top of the guides. Using heavy-duty dual valve springs and chromoly pushrods is highly recommended to handle the increased aggressive ramp speeds and high-RPM stability required by this camshaft profile.

3. Optimize Intake and Exhaust for High-Range Power

The GT-7 is a high-range power cam, meaning it needs to "breathe" to be effective. Pairing this cam with stock 34-series carburetors or a restrictive factory exhaust will "choke" the engine and prevent the cam from reaching its potential. To truly utilize the 295-degree duration, we recommend a dual-carburetor setup (such as Weber IDFs or EMPI HPMXs) and a merged competition-style header with a minimum 1-5/8" tubing diameter. This setup ensures that the intake charge and exhaust scavenging are synchronized with the GT-7''s aggressive timing, resulting in a broad, violent power band in the upper RPM ranges.