Turbo Kits currently available?

[Grumpy Ole Codger]

Now I'm going to reveal my ignorance on topics mechanical. What is the difference between having a super charger fitted and a turbo? As far as my understanding goes, they both pressurise the intake forcing more air into the combustion chamber and therefore bigger bangs and more power. So which is better on a bike like the Rocket?

 

[Joesmoe]

Takes a special kind of person to document properly.

As a young lieutenant learning the ways of aviation acquisition in the then-new F-16 program, I remember distinctly going over various cost elements, and noting at the time the relatively high cost of a tech writer, and asking why. One of the managers explained, "He has to be as smart as the engineer designing the airplane, and know how to write and explain it to pilots and mechanics.

I could see taking a vacation and filming your work and documenting it, even if for my own benefit.

My highest praise (apart from the quality achieved with millions of dollars available on fighter aircraft tech pubs) goes to the Haynes manuals before the internet age, where their standard practice was to take apart a real car and document what is *really* required for various repair operations.

One aspect of my love for R3Owners.net is the penchant for some owners to do that and share.

 

[Navigator]

My highest praise (apart from the quality achieved with millions of dollars available on fighter aircraft tech pubs) goes to the Haynes manuals before the internet age, where their standard practice was to take apart a real car and document what is *really* required for various repair operations.

One aspect of my love for R3Owners.net is the penchant for some owners to do that and share.

Ditto Paul. Back in 1983 I rebuilt my "crate find" 1967 Triumph TR6C on my back porch along the edge of a minefield in Guantanamo Bay, Cuba, using a Haynes manual that I still have. I read/hear guys knock the Haynes but to me they simplify a job that the factory manuals make difficult. I've got over 50 vintage/classic bike manuals in my shop library, many of them Haynes.

And I wrote/developed many Title K and D SHIPALTS on numerous ship classes "back in the day" and contracted the tech manuals for them. I'd read them over prior to acceptance and kick them back if they were was incoherently technical and difficult to understand. No "engineering fun" I'd tell them.

 

[Claviger]

Now I'm going to reveal my ignorance on topics mechanical. What is the difference between having a super charger fitted and a turbo? As far as my understanding goes, they both pressurise the intake forcing more air into the combustion chamber and therefore bigger bangs and more power. So which is better on a bike like the Rocket?

Super chargers are driven by a belt rotating on a pulley attached to the crank, turbo is driven by exhaust gases. Fundamentally they do the same job, but get there in different ways.

If you took 3 bikes to 250whp, one Supercharged, one turbo, and one all motor, they would feel completely different to ride.

There really isn’t a “best” overall, but there is a best for different uses.

Turbo will make the most torque and do it at the lowest RPM, but the trade off is a slightly delayed throttle response. It will also get the best mileage when cruising (the turbo increases overall engine efficiency if sized right). Will return the worst real world mileage most likely though. Boost (torque) is directly proportional to throttle position and largely RPM independent.

The all motor bike will be the sharpest throttle response and will be the most reliant on RPM to make horsepower. Generally will return the best real world mileage. Torque is directly related to both RPM and throttle position.

The supercharged (centrifugal) bike will have the broadest torque curve and the most linear one. It will have very good throttle response, in most cases it will return the worst cruising mileage. Boost (torque) is tied directly related to RPM and largely independent of throttle position (unless a bypass valve is used).

Not hard and fast rules, as you can engineer some of each methods traits out. The missing piece is a positive displacement supercharger, but there isn’t one available for the R3. The PD SC blends the low end torque of the turbo with the very broad torque curve of the centrifugal blower, but the trade off is gas mileage. PD SC is has boost (torque) controlled by RPM and limited by using a bypass valve, no bypass valve systems are largely a thing of the past on PD setups.

Given a perfect world, I’d choose a carpenter 210 kit with a PD SC attached

 

[juice_man_86]

Turbos are also easier to add or remove available horsepower. Via a wastegate. I like to use the term adjustable horsepower. You can even have a low and high boost setting with the flip of a switch. Often referred to as overboost. To adjust the hp in a supercharged motor you have to physically change pulley sizes.

 

[Grumpy Ole Codger]

Super chargers are driven by a belt rotating on a pulley attached to the crank, turbo is driven by exhaust gases. Fundamentally they do the same job, but get there in different ways.

If you took 3 bikes to 250whp, one Supercharged, one turbo, and one all motor, they would feel completely different to ride.

There really isn’t a “best” overall, but there is a best for different uses.

Turbo will make the most torque and do it at the lowest RPM, but the trade off is a slightly delayed throttle response. It will also get the best mileage when cruising (the turbo increases overall engine efficiency if sized right). Will return the worst real world mileage most likely though. Boost (torque) is directly proportional to throttle position and largely RPM independent.

The all motor bike will be the sharpest throttle response and will be the most reliant on RPM to make horsepower. Generally will return the best real world mileage. Torque is directly related to both RPM and throttle position.

The supercharged (centrifugal) bike will have the broadest torque curve and the most linear one. It will have very good throttle response, in most cases it will return the worst cruising mileage. Boost (torque) is tied directly related to RPM and largely independent of throttle position (unless a bypass valve is used).

Not hard and fast rules, as you can engineer some of each methods traits out. The missing piece is a positive displacement supercharger, but there isn’t one available for the R3. The PD SC blends the low end torque of the turbo with the very broad torque curve of the centrifugal blower, but the trade off is gas mileage. PD SC is has boost (torque) controlled by RPM and limited by using a bypass valve, no bypass valve systems are largely a thing of the past on PD setups.

Given a perfect world, I’d choose a carpenter 210 kit with a PD SC attached

Brilliant and in laymans terms for the lesser educated of us - Thank you!!

 

[Speedy]

Turbochargers use exhaust gas pressure generated by combustion heat to pump intake air. The more boost the greater the heat and pressure in the cylinder during the exhaust stoke. The heat load on an engine is in proportion to the torque generated. Thus, low rpm torque places demands on the radiator and engine oil that can be difficult to control. Piston skirts and crowns, rings and valves are subjected to higher heat for extended times (at 2,000 rpm the power stroke lasts twice as long as it does at 4,000 rpm.) High cylinder heat combined with higher intake temperatures from compressing the intake charge can lead to catastrophic failures. Oil coolers, over sized radiators, intercoolers and ignition timing control and detonation sensing are often needed to manage the extra heat. Water injection is commonly used as well, and to those unfamiliar with its use, in surprising quantity.

If designed and executed well turbocharging is very effective. However, more often than not, self designed and installed systems end up under the work bench along with a pile of pistons, a cracked head or two, and at least one broken crankshaft. Not for the faint of heart or those with thin wallets.

When do we start?

 

[Claviger]

So preliminary parts list goes something like this:
550cc Injectors
One of these turbos internally gated style single scroll: GTX 2252, GTX 2860R, KO3 Super 42, GT2860RS, GTII2860
Matching SS flange for turbo mount
2 meters of Schedule 40 304 or 321 SS for manifold
2 meters of 2.25 Aluminum charge pipes
1 2.25" T aluminum tubes (intake manifold)
2 2.25" 90 degree aluminum tubes (intake manifold)
PC-V 3 bar map sensor
Turbosmart Eboost Boost controller and mounting cup
2 momentary switch to signal boost controller of gear changes
walbro 255lph pump
PC-V
PC-V Autotune (not to autotune, but for wideband readings)
lots of silicone couplers
Bosch 317 GPH electric water pump
Water to Air straight through intercooler 4x8 barrel type core
air to air heat exchanger for intercooler fluid and associated hoses
assorted bolts/nuts/etc
BOV of choice
sacrificial stock header
10 feet of 3" 304 SS exhaust tube for the exhaust behind the turbo
matching flange for selected turbo to exhaust
oil cooler and associated hoses

I'm sure more will come to mind as I think this through, but the one thing I'm not yet clear on how i'll solve is the oil feed and dump for the turbo, need to look at the oil circuit for the R3 and find a couple of good points to use.

 

[Speedy]

The best performing turbo systems treat the entire intake system just like its naturally aspirated. No sharp bends, smooth transitions, no abrupt volume changes, tuned runner lengths, etc. Compressed air is denser than atmospheric air, therefore sonic activity is stronger than when naturally aspirated. If the runners are too long or too short performance is reduced. Design a proper intake plenum. Don't short cut here. A couple of elbows and tees are way too crude to be effective. Think about some of the intake plenums with internal bell mouths and intentional volumes designed by various members to mount air filters.

Keep the turbo as close as practical to the exhaust ports. Individual exhaust pulses have lots of energy to harness. Look at mounting the turbo at the front of the engine on a log type manifold with the compressor axis vertical. This leaves a short distance to an air to air charge cooler in front of the radiator. Perhaps a second electric fan for low vehicle speeds for the intercooler and to assist the radiator fan. The cooler could exit on the engine intake side and route almost straight back to the plenum. Think about adding two injectors ports at the entry to the plenum. Use one for water/alcohol and the other for some of the fuel enrichment. That fuel will drop the intake temperature and follow the fastest airstream into whichever intake valve is opening. This often works better than just adding more fuel through the normal injectors alone.

Tune cam timing to compliment the higher exhaust pressure during overlap. Be careful of too much cam duration if you want low rpm torque. Some exhaust gas retention will reduce peak cylinder temperatures but too much robs power. The exhaust valves will run hotter so watch valve lash, a little more is better than not enough. With the bucket tappets in Carpenter's heads you won't spit out a shim running more lash clearance. If the exhaust valves don't seat well, the valves will over heat rapidly as they lose the ability to transfer heat to the seat.

Keeping the turbo high will allow you to use a gravity oil return system rather than a scavenging pump. Turbos hate back pressure on the oil exit side so large gravity lines are needed. If possible use a water cooled turbo too. Route engine coolant through it. This warms the bearings up and keeps them a more consistent temperature.

Keeping the system as simple as practical and easy to tune will help with system and engine reliability.

 

[Joesmoe]

Sir @Speedy : that is pure poetry.

Gentlemen: This really is ROCKET Science.