Twin-Turbo EngineTruck

Engine Block
The 4.125" bore custom block is built to Banks' specs by Dart. It is cast from a high nickel alloy and is equipped with splayed main caps and ARP head studs for superior strength.

Cylinder Heads
The head design evolved after many hours of research on the part of the Banks Race Shop. The result is the optimum 23° aluminum head for use with the Banks Twin Turbo System. It features custom CNC ported intake and exhaust ports as well as a unique combustion chamber. The heads house 2.080"/1.600" Severe Duty Valves, Banks 1.470" double valve springs and 10° Chrome-moly retainers. This unique combination promotes maximum power output while providing optimum durability.

Crankshaft
A 3.5" stroke crankshaft is the heart of the 6.15L/375ci Turbo engine. Cut from a non-twisted 4340 forging and precision balanced to our specs, it is designed for power levels well in excess of 1100HP. Chosen for its superior quality, strength and durability, it will provide a lifetime of trouble-free use even in the most extreme environments. A Fluidampr Harmonic Balancer controls torsional vibrations.

Pistons and Rods
Years of race engine building experience has resulted in the optimum performance design for turbocharged applications. The Banks forged pistons are custom machined to provide the 8.5–1 Compression Ratio needed to optimize street and strip performance as well as the necessary valve clearance. They feature a 1/16, 1/16, 3/16" ring pack, which is uniquely located for better sealing and longer ring life. Connecting rods are 4340 Forged H-beam rods with ARP 7/16" rod bolts, chosen for their remarkable strength, light weight and durability.

Camshaft and Rockers
The Banks turbo engine uses a solid roller Comp Cam with a Banks custom lobe design. The lightweight lifters actuate custom length 5/16 " pushrods as well as the Jesel Shaft-mounted Roller Rockers. The camshaft is custom ground to maximize cylinder head design.

Induction
The massive amount of air needed to make 800HP is fed to the engine via a Banks-designed pressure chamber with an integral shuttle valve and a billet throttle body. Both sit atop an Accel Pro-Ram manifold, which is CNC port matched to fit our heads. The high port runners optimize air movement and help broaden the torque curve.

Fuel and Spark
Fuel Injection and spark management is provided by Accel DFI. Their proven system, combined with the thousands of hours logged on the Banks dynamometers plus on-the-road testing, has resulted in a truly solid calibration, which works equally well with manual or automatic transmissions. Idle quality, drivability, mileage, and wide-open throttle have all been addressed with this sealed calibration. The calibration is designed to provide safe fuel and spark management with a minimum of 91 octane fuel for everyday driving, and 100 octane fuel for maximum boost situations.

Exhaust Manifolds
These compact, high-flow manifolds were designed by Banks for the ultimate in fit and long-term durability. Their unique design resists cracking and distortion while providing the best turbo and wastegate placement for ease of installation.

Wastegates
The Banks BigHead® Wastegates are designed for a flat boost curve resulting in an awesome power transition. The high-gain actuator allows for quicker spool-up and less boost creep. The stainless steel body withstands the high temperatures, ensuring a long and reliable service life.

Turbochargers
The high-flow turbochargers, built by Banks to our own strict specifications for optimum performance, deliver outstanding power from their compact frames. With our precision-balanced inconel turbine wheel and shaft assembly, the assurance of durability and reliability is never in question. Driving is a smooth, pulse-pounding power fest that gives you the "nailed back in your seat" thrill you'd expect from Banks. The efficiency of our compressor design helps to reduce inlet air temperatures to acceptable levels, eliminating the need for an intercooler.

Front Accessory Drive
The compact design of the CNC’d billet aluminum front accessory drive aids with the installation of the Banks Twin Turbo engine into many vehicles. A single serpentine belt drives a high output alternator, AC compressor, high-volume water pump and power steering pump. Billet pulleys complement the high-tech look of this system.

Final Testing
Each Banks Twin Turbo Engine is tested in our dyno cell for one hour, following a proven automated break-in procedure. After valve lash checks, leak-down and compression tests are taken, the engine is given a number of full throttle power runs to verify performance. This assures that each engine is performing to the high standards of excellence set by Gale Banks Engineering.

Packaging
When customers receive the Banks Twin-Turbo Engine, it includes an engine wiring harness, which they can customize to their application. Included with the engine are exhaust flanges, wastegate flanges, pressure regulator, and fuel pump. An owner’s manual, installation instructions, and dyno sheets are also supplied with the package. Gale Banks Engineering will also work with the customer to create that perfect look for their application. Polishing, chrome plating, anodizing and color coordination can all be worked out to create the desired finished product.

Banks Twin-Turbo Systems are also available
Application Year Range Part #
Twin-Turbo engine
Small-block Chevy V-8, 800-1100 hp 10800

Twin-Turbo engine dyno'd at 1100 hp

Gale Banks Engineering built a Twin-Turbo engine for a customer's '69 Camaro in Australia, and this is it being tested on a dynamometer. The results: 1100 hP