EDELBROCK PERFORMER HEAD 1984-99 EVO BIG TWIN HARLEY
Price: $1,157.95
PERFORMER HEAD
Features
Cast out of 356 aluminum and heat-treated to T-6 specifications
Feature 35% gain at peak torque, 92% gain at peak horsepower over stock with the use of aftermarket cam (Edelbrock 1740 grind, DS-199197), carburetor and pipes
Broad power curve for excellent driveability and crisp throttle response throughout the rpm range
Rectangular-shaped intake port increases surface area of the floor for noticeable airflow increase
The .125” raised rectangular intake port also helps to increase velocity of incoming air for more power
The 72cc combustion chamber increases compression ratio from 8.5:1 to 9.5:1
Heads will accept up to a .570 lift cam and bore size up to 31 3/16” (some machining required)
Street-legal in all 50 states; patent pending
Heads require the use of Edlebrock three-piece manifolds (sold separately)
Replacement components available separately; made in the U.S.A.
1. Rectangular Shaped intake Port Edelbrock's unique rectangular-shaped intake ports are the first V-Twin motorcycle ports designed to create a laminar flow for the incoming air-fuel mixture charge. The flat floor of the intake port slows the lower section of the charge down as it crosses the lower short side radius; this flow rate is equal to the speed of the upper charge as it moves along the top of the port. The smoother flow eliminates charge turbulence and makes for a more evenly atomized intake mixture. This is the most efficient port shape that can be developed in the working space available in V-Twin cylinder heads. An Edelbrock intake manifold with matching rectangular ports must be used with all Edelbrock heads.
2. Dual-Quench Combustion Chamber The dual-quench combustion chamber of the Big Twin and Twin Cam heads features a patented design that creates more turbulence on the compression stroke for a more uniform mixture which prevents pinging and detonation. This results in more efficient combustion for more power from idle to redline, better cruising capabilities and better mileage.
3. "D" Shaped Exhaust Port The "D" shaped exhaust port is designed to provide a larger area for increased flow and velocity as well as to create a mismatch between the exhaust pipe and the exhaust exit. This purpose-built mismatch reduces "power-robbing" reversion by keeping the majority of the exhaust gasses from going back into the engine.
SUPERIOR FEATURES OF ALL EDELBROCK HEADS All Edelbrock cylinder heads include high-grade stainless steel swirl-polished valves, ductile iron seats and guides, Teflon® valve stem seals, radius valve job, and heavy duty valve springs. They are made of A356 aluminum heat treated to T-6 specs. Edelbrock heads must be used with Edelbrock manifolds for maximum performance (see page 18 & 19). Valve spring specs for Performer RPM heads: maximum valve lift .650", 1.460" OD with dampener, installed seat pressure 175 lbs., installed height 1.800", titanium retainers and 7º locks. VELOCITY IS KEY FOR INCREASING PERFORMANCE The volume of air that a cylinder head can pass is important. While Edelbrock cylinder heads produce excellent cfm results, volume is just one component of effective air flow. Velocity is the other component, it is a measurement of how fast a given volume of air travels. High-velocity airflow provides quick throttle response, awesome acceleration and excellent mid-range power. Edelbrock heads are a balance of volume and velocity.
