Trask Injected Bagger Turbo System

(1.)Shown is Jesse’s ’07 96-cubic inch Twin Cam Street Glide that dynoed at 71.1 horsepower and 85.9 lb-ft of torque in stock trim.

(2.)The Trask Injected Bagger Turbo System includes a precision billet plenum with snap-in high-flow venturi, modified Garrett GT turbocharger, ceramic-coated exhaust system, high-flow injectors, air cleaner, head breathers, performance Barnett clutch spring, and all necessary assembly hardware.

(3.)The modified Garrett GT22 turbo is the heart of Trask’s Turbo System and is matched to the Twin Cam’s airflow requirements. The turbo is preset for 8 pounds of boost pressure.

(4.)Turbo installation started with the removal of the stock TC air cleaner assembly and exhaust system.




If you’re a Harley performance enthusiast, we’re sure you know that there are several ways to make power-several ways to skin a cat, so to speak. For instance, some guys prefer lots of cubic inches while others are more comfortable with a high-revving small engine. Still others like pulling up to the boy’s club with a power adder like a turbo. Nick Trask, owner of Trask Performance in Phoenix, Arizona, is just one of those guys-a turbo type of guy, that is. And so is Jesse James of West Coast Choppers in Southern California. Since Jesse was looking for a power boost for his ’07 96-cubic inch Street Glide without having to disassemble the entire engine, he contacted Nick to see how development of his new Bagger Turbo System was going. If you’ve been following HOT BIKE, you probably know that Nick builds some great turbo systems for the V-Rod and was developing a similar line of turbos for Harley Baggers. Fortunately, Nick was putting some finishing touches on his new Bagger Turbo System and asked us to follow along as his crew performed the install on Jesse’s bike.
Trask’s new Injected Bagger Turbo System is intended for ’02 and later Delphi-equipped Twin Cam baggers. It is designed to give heavily loaded 88- and 96-cubic inch engines a smooth, streetable power boost on pump gas that will flatten out steep mountain grades-make passing 18-wheelers a breeze-and turn riding two-up and heavily loaded into a pleasurable experience. When installed and tuned properly, you can expect the Trask Turbo Bagger System to produce between 100-130 horsepower and 100-130 lb-ft of torque with 8 pounds of boost and 91-octane pump gas. Fortunately for Twin Cam owners, unlike Evolution crankcases, Twin Cam cases are stout and can handle that level of power.
The Trask Injected Bagger Turbo System comes as a complete package, including a Patent Pending precision billet plenum and snap-in venturi for unobstructed airflow, a modified Garrett GT turbo, ceramic- and chrome-coated pipes, high-flow injectors, performance Barnett clutch spring and assembly hardware. Also included are an instructional CD and EFI fuel maps. The turbo kit is designed to run on pump gas and use stock TC camshafts, throttle body and compression ratio. The only additional item you need is a Harley-Davidson SE Race Tuner or Dynojet Power Commander so the fuel injection’s ECM can be recalibrated with the proper fuel curve.
Before installing the Injected Bagger Turbo System, Trask Performance dynoed Jesse’s 96-cubic inch Twin Cam engine. The stock engine dynoed at 71.1 horsepower and 85.9 lb-ft of torque. After the Trask turbo installation, the engine produced 112.6 horsepower and 117.0 lb-ft of torque. That represents a 58-percent horsepower and 36-percent torque increase with stock compression, 91-octane pump gas and without requiring any internal engine modifications. If you have a heavy bagger and are looking to increase performance, turbocharging is one of the most cost effective ways for producing smooth, rideable horsepower. And you can effectively ride all day without getting on the boost, so fuel economy and reliability are not compromised. Jesse will have smooth sailing up the PCH while rousting the gulls and pelicans from their perches on buoys and piers with the steady, rhythmic rumble of 112 hp from his Trask turbo-equipped bagger.
(5.)Next, the throttle body was removed to install high-flow injectors and a vacuum fitting for the turbo’s blow-off valve.
(6.)The stock Delphi fuel injectors were replaced with high-flow injectors to keep up with the increased airflow and fuel demands created by the forced induction of the Garrett turbo.
(7.)The throttle body’s plenum was drilled and tapped for a fitting that would supply a vacuum source to the blow-off valve. The blow-off valve relieves intake tract pressure when the throttle is closed and aids throttle response when opening the throttle.
(8.)The turbo unit was lubricated with pressure-fed oil from the TC engine. The engine’s oil pressure switch at the front of the crankcase was removed and replaced with a T-adapter that supplies oil to the turbo unit from one end of the T-adapter. The oil pressure switch was then connected to the other end of the tee.
(9.)The turbo’s lubricating oil is routed back to the engine and drained into the gearcase. Early Bagger Turbo Systems required drilling and tapping the stock TC cam cover for an oil return fitting. The latest systems include a new high-quality billet cam cover with the oil drain fitting installed.
(10.) Next, the fuel pump was removed from the fuel tank to install a boost-pressure line that allows the fuel pressure to be raised above stock levels based on any increase in turbo boost. For example, if boost pressure rises to 8 pounds, fuel pressure also rises 8 pounds above the stock level, which is typically 55-60 psi.
(11.)Then the fuel tank access plate was drilled to install a bulkhead fitting for the fuel pressure’s boost-pressure line.
(12.)The stock fuel regulator was then tapped for a fitting. The fitting will be connected to the fuel tank’s boost-pressure bulkhead fitt- ing (T-fitting) with a line. Another line will connect the opposite side of the bulkhead fitting to the intake air plenum. The boost-pressure line provides positive pressure to the regulator to maintain fuel pressure at a 1:1 ratio with any increase or decrease in turbo boost pressure.
(13.)Next, the exhaust header pipe was installed. A black exhaust system was used on Jesse’s bike. Other exhaust options include all chrome, and chrome and black.
(14.)The Garrett turbo unit was then attached to the exhaust and induction systems.
(15.)Once the turbo unit was fastened down, the exhaust pipe was installed to the turbo.
(16.)Two one-way billet breather valves replace the stock cylinder head vent bolts. The cylinder heads will now vent crankcase air through the two breathers.
(17.)The velocity stack was then fastened to the stock throttle body.
(18.)The velocity stack cover was installed next. The velocity stack and cover create a plenum area in the intake tract.
(19.)Finally, a Barnett MT8 clutch spring was installed to handle the engine’s increased torque and horsepower.
(20.)Here is Jesse’s finished Street Glide. A black Trask Bagger Turbo System was selected to match the bike’s color scheme. Also available are all chrome and chrome/black systems. With the correct tools, a technically minded owner should be able to install the Trask Bagger Turbo System in six to eight hours in their home garage. Keep your eyes peeled for a full feature on this bikein an upcoming issue of our sister publication HOT BIKE BAGGERS.
(21.)Here is the dyno chart from Jesse’s turboed engine. The red lines indicate the stock engine’s HP and TQ curves while the blue lines represent the modified turbo engine with 8 pounds boost, stock compression ratio, stock cams and 91-octane gas. Torque peaks on the turbo engine at about 3,350 rpm (117.0 lb-ft) and horsepower (112.6) at 6,300 rpm. The turbo engine maintains at least 100 lb-ft of torque from roughly 2,700 rpm to 5,700 rpm. Note that the stock engine maxes out at only 85.9 lb-ft. of torque.