01. Here is the Trask Turbo kit ($4,995) that was ordered for Ron’s bike. The kit is designed for carbureted or EFI ’00-later Softails and ’99-later Dynas. This kit came in a sinister black finish and some of the main components include: an exhaust manifold and exhaust pipe with heat shields, turbo housing, plenum, a boost gauge, billet breathers, an air filter, a Zippers two-bar sensor, a billet cam support plate, and a Barnett high-performance clutch spring.
01. Here is the Trask Turbo kit ($4,995) that was ordered for Ron’s bike. The kit is desi
Last issue in “Dyna Suspension Upgrade,” we introduced you to Ron and his ’11 Dyna. In that article we mentioned that Ron likes to ride hard and push his bikes to the limit, which was the reason for upgrading the rear suspension with the Progressive 970 series shocks. Not one to tread lightly, Ron also likes to beef up his bikes with added horsepower and torque and he’s had it all, from big bore kits to strokers. So when it came to hop up his new Dyna, he figured why not try a different route and start out with a power-adder like a turbo from Trask Performance.
Ever since he moved to the US from New Zealand, Trask Performance Owner Nick Trask has been continually developing his line of turbo systems to put out dependable, streetable power that will result in significant performance gains. While we’ve covered the installations of a Trask Turbo on several occasions over the years, we figured we would give those of you unfamiliar with turbo systems a little background on its basic principles and then delve into some of the major components that make up a Trask Turbo kit.
02. Here’s the heart of the kit, a modified Garrett turbo. The turbo is comprised of three main housings. On the left side is the turbine housing (red arrow) where the exhaust gasses enter and spin the turbine wheel. In the center is the housing for the common shaft and its bearings/bushings, which are fed with oil via the fitting up top (yellow arrow). Then on the right side is the compressor housing where the charged air is created and then sent to the intake via the tube coming off the top of the housing (blue arrow). On the front of the turbo unit is the waste gate assembly, which controls boost pressure via an actuator assembly and a calibrated 8-pound spring in the cylindrical housing (green arrow).
02. Here’s the heart of the kit, a modified Garrett turbo. The turbo is comprised of thre
The first thing to remember with a Harley engine (or any internal combustion engine for that matter) is the key to making more power is stuffing more air into the cylinders. More air means more fuel and a bigger combustion creating more energy pushing down on the pistons and more power output at the crankshaft. Hence the reason why the simple addition of a larger air cleaner can easily add 5 horsepower. A normally aspirated engine depends on atmospheric pressure (14.7 psi at sea level) and the vacuum created by the downward stroke of the pistons on the intake stroke to draw in air. However, a stock engine doesn’t completely fill the cylinders as it cycles. The addition of a turbo system and its ability to create pressurized, charged air, and flow more air into the cylinders than atmospheric pressure alone would, means the volumetric efficiency (percentage of quantity of fuel and air that enter the cylinders during induction to the actual capacity of the cylinder under static conditions) can easily reach more than 100 percent. Boost (increase in manifold pressure above atmospheric pressure) is the measured amount of charged, pressurized air coming out of the turbo. Boost is measured in pounds per square inch (psi). More boost means more air will be forced into the engine creating more horsepower.
03. Looking into the right side of the turbo you can see the compressor wheel. As the wheel speeds up it creates the charged air. A high-flow filter gets fitted over the front of the compressor housing.
03. Looking into the right side of the turbo you can see the compressor wheel. As the wh
So how does the turbo create the pressurized, charged air? Exhaust gasses. Within the turbo housing are two impeller blades (a turbine wheel and compressor wheel) with a common shaft running between them. An exhaust manifold directs the spent gasses from the engine’s exhaust ports to the turbo housing. The velocity of the gasses spins the turbine wheel, which turns the common shaft and compressor wheel connected at the other end. As the compressor wheel spins faster and faster the air becomes compressed, charged air. The charged air exits the compressor housing at a higher velocity and then finally makes its way to the intake and stuffs the cylinders with more air. More air, a little more fuel, and you can create more power.
The Trask Turbo system is designed as a bolt-on system that will create 8 psi of boost and will provide a significant power increase without having to dive into the engine—that is if you keep the engine mostly stock.
04. Here’s the inside of the left side of the turbo. Here we see the turbine wheel and the other end of the waste gate actuator. As we said earlier, the waste gate controls boost pressure. It opens and closes to maintain or expel exhaust gasses and maintains the turbo- charger’s shaft speed. When pressure can overcome the 8-pound spring, the actuator assembly opens the internal waste gate and anything over 8 pounds of boost is bled out through the exhaust.
04. Here’s the inside of the left side of the turbo. Here we see the turbine wheel and th
05. Looking at the bottom of the turbo we see where the down pipe/exhaust pipe mounts and where the exhaust and extra boost is expelled out of the system. You will also notice the brass elbow on the bottom of the shaft bearing/bushing housing. This fitting is where the oil that is fed into the housing exits and returns into the cam chest.
05. Looking at the bottom of the turbo we see where the down pipe/exhaust pipe mounts an
06. The Trask billet cam cover features a brass fitting at the top, which is where the oil we previously mentioned is fed back into the cam chest. The cover has four threaded standoffs to secure the exhaust manifold brackets.
06. The Trask billet cam cover features a brass fitting at the top, which is where the o
07. This is the inside of the billet plenum, which is mounted to the throttle body. The air exits the turbo and enters the plenum. At the center of the plenum is a venturi, which provides unobstructed airflow into the throttle body.
07. This is the inside of the billet plenum, which is mounted to the throttle body. The a
08. On the backside of the plenum is a blow-off valve (arrow). The blow-off valve is a spring-loaded valve that is connected to a line that is tapped into the backside of the butterfly in the throttle body (vacuum side of the engine). When you’re on the bike at full throttle/full boost and then you close the throttle body off and go from 8 pounds to nothing, it creates pressure, which creates a vacuum that sucks open the blow-off valve to relieve excess boost pressure left inside the manifold. This helps prevent compressor surge, prevents slowing the turbo down, helps the turbo last longer, and increases responsiveness.
08. On the backside of the plenum is a blow-off valve (arrow). The blow-off valve is a s
09. Here we see the black ceramic-coated exhaust manifold, exhaust pipe, and heat shields. The end of the exhaust pipe features a billet end cap.
09. Here we see the black ceramic-coated exhaust manifold, exhaust pipe, and heat shield
10. The under side of the exhaust manifold features O2 sensor ports for monitoring the EFI system.
10. The under side of the exhaust manifold features O2 sensor ports for monitoring the E
Lucky for us Ron doesn’t mind experimenting with different power upgrades on his bike. So while we are going to start off with the Trask Turbo, other hopups, such as larger cams and possibly an increase to 103 ci, are likely to occur shortly down the line. With that being said, and the fact that Ron can get pretty wild when it comes to riding his bikes, the decision was made to tear the engine down, split the cases, and beef up the lower end. While it’s not an absolutely necessary step when adding a Trask Turbo to a bike, Nick was made aware of the additional power modifications and suggested that reinforcing the lower end would be a smart move. There are a couple modifications that can be performed on the TC’s lower end that will make it more robust, sustainable to high horsepower/higher loads, and help prevent potential internal catastrophe.
11. To let you know where you’re at boost-wise, the kit comes with this handlebar-mount boost gauge. The gauge housing is made of billet aluminum and mounts to the right-side handlebar switch assembly.
11. To let you know where you’re at boost-wise, the kit comes with this handlebar-mount
The first of which is converting the straight roller bearing in the engine’s left-side case to a more durable tapered Timken roller bearing setup. As the TC engine gets hopped up and makes more and more power, the high-speed flexing of the crankshaft can put additional stress on the stock roller bearing which can cause the bearing’s outer race to fracture and disperse broken metal throughout the lower end causing major havoc. JIMS Machine and H-D’s Screamin’ Eagle line both offer a Timken bearing kit along with a Timken bearing sleeve that allow you to install the bearings without having to machine the case. The sleeve is precision machined and made from high-quality steel that is much stronger than the stock bearing setup. The sleeve and dual tapered bearings make for a more durable setup.
12. For EFI setups Trask suggests several aftermarket tuning systems, but they highly recommend the Zippers Thunder Max with Auto Tune. Trask prefers this system because of its extensive and in-depth tuning capabilities. Included is a CD with proper mapping to be loaded into the Thunder Max.
12. For EFI setups Trask suggests several aftermarket tuning systems, but they highly rec
Another modification that can be done to further beef up the lower end is to weld the crank. The stock crank is a three-piece, pressed-together assembly with the crankpin “hard” pressed into the flywheels. While under normal circumstances this setup is usually OK, once again as power significantly increases the additional stress and load can cause the crank assembly to twist. This twisting can cause the assembly to become out of true and can lead to a wobbling pinion shaft. A wobbling pinion shaft can lead to major or catastrophic problems. The solution is to true up the assembly to within 0.001 inch and then weld each side of the crankpin to the flywheel halves. With each side adequately welded, the assembly is then re-trued to within 0.001 inch.
12.5 To go along with the Thunder Max is a two-bar map sensor which reads boost pressure and feeds a signal to the Thunder Max so the system can add fuel or retard timing, and make adjustments as needed.
12.5 To go along with the Thunder Max is a two-bar map sensor which reads boost pressure
In this article we will first look at some of the components that make up the Trask Turbo kit for this ’11 Dyna. We will then show you some of the precautions we spoke of that Anaheim-Fullerton Harley-Davidson took to make sure the lower end of Ron’s Dyna would be prepared for the other power upgrades that get thrown at it. HB
13. Another item that is included is a Barnett high-pressure clutch spring. Swapping out the stock spring with this spring helps the clutch harness the additional power.
13. Another item that is included is a Barnett high-pressure clutch spring. Swapping out
14. These H-D 4.9 g/s High Flow injectors replace the stock injectors and allow more fuel to be sprayed in with the additional air.
14. These H-D 4.9 g/s High Flow injectors replace the stock injectors and allow more fuel
15. So those were the major components of the Trask Turbo assembly. Now we’ll take a look at what Anaheim-Fullerton Harley-Davidson did to reinforce the lower end of Ron’s Dyna.
15. So those were the major components of the Trask Turbo assembly. Now we’ll take a loo
16. Service tech, Matt Cortez, made quick work of disassembling the engine. Here we see the sprocket shaft side (left side) of the stock flywheel assembly. You can see it’s a three-piece assembly with the crankpin hard-pressed into the flywheels. Under high loads and excessive power, the assembly can twist and become unbalanced.
16. Service tech, Matt Cortez, made quick work of disassembling the engine. Here we see
17. To combat the potential for twisting the pin gets welded to the flywheels. Welding is done on both the sprocket and pinion side of the crankpin. The flywheels are trued before and after welding.
17. To combat the potential for twisting the pin gets welded to the flywheels. Welding is
18. Along with the flywheel assembly another potential weak point is the straight roller bearing in the left engine case. Once again as the engine makes more power, more stress is put on this bearing. Excessive power and loads can cause the bearing’s outer race to fracture and break apart dispersing metal fragments throughout the engine and oiling system.
18. Along with the flywheel assembly another potential weak point is the straight roller
19. The solution is to replace the bearing with this Timken bearing sleeve and dual tapered Timken bearings. Offered by JIMS Machine and H-D’s Screamin’ Eagle line, this sleeve is made out of high-quality steel and the addition of the Timken bearings make for a much stronger, more durable setup. Here we are looking at the inside of the left case half. The Timken setup doesn’t require precision machining, but the case does have to be drilled and tapped so the sleeve can be secured in place.
19. The solution is to replace the bearing with this Timken bearing sleeve and dual tape
20. Here’s the outside of the left-side case half. The Timken conversion kit requires a jig assembly so that the holes for the sleeve can be properly drilled and tapped.
20. Here’s the outside of the left-side case half. The Timken conversion kit requires a
21. When it comes to installing the dual tapered Timken bearings, Matt starts by setting up bearing endplay. He first uses a dummy shaft to find out which size shim is needed to achieve the specified 0.001-0.005 inch of bearing endplay. Matt prefers to come in at 0.003 inch. To accomplish this when setting up the dummy shaft, he aims for the high end of the specified measurement because he knows once he presses everything together, the shim will swell up and he will lose 0.002 inch leaving 0.003 inch of end play.
21. When it comes to installing the dual tapered Timken bearings, Matt starts by setting
22. Matt found that a 0.113 inch shim gave him the initial 0.005 measurements he was looking for.
22. Matt found that a 0.113 inch shim gave him the initial 0.005 measurements he was loo
23. The flywheel assembly was then secured and the inner tapered Timken bearing was installed on the sprocket shaft followed by the 0.113 inch shim.
23. The flywheel assembly was then secured and the inner tapered Timken bearing was insta
24. The left side case was then slid over the shaft and the outer tapered bearing was slid in place.
24. The left side case was then slid over the shaft and the outer tapered bearing was sli
25. The bearing was pressed into the sleeve and then…
26. …Matt double-checked to make sure he achieved the 0.003 inch of bearing endplay he was shooting for.
26. …Matt double-checked to make sure he achieved the 0.003 inch of bearing endplay he w
27. Matt then applied some H-D High Performance sealant to the mating surface of the left side case half and then…
27. Matt then applied some H-D High Performance sealant to the mating surface of the left
28. …slid the right-side case half into position and torqued the case bolts to spec.
28. …slid the right-side case half into position and torqued the case bolts to spec.
29. The lower end was then placed back into the frame and mated to the transmission.
29. The lower end was then placed back into the frame and mated to the transmission.
30. Due to the sleeve with the Timken conversion, a shorter sprocket shaft spacer had to be used.
30. Due to the sleeve with the Timken conversion, a shorter sprocket shaft spacer had to
31. Finally at the primary, the stock clutch spring was replaced with the Barnett High Performance clutch spring. OK, so now we’ve showed you the main components of the Trask Turbo system and how Anaheim-Fullerton H-D took some precautions to reinforce the lower end of Ron’s bike in preparation for the additional hopups that will come down the line. Check back next issue as we show the installation of the turbo, then throw the Dyna on the dyno for some horsepower and torque results.
31. Finally at the primary, the stock clutch spring was replaced with the Barnett High P
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