The rendered 3D CAD models are great in helping us visualize what the kit will look like, but nothing compares to seeing the actual production pieces. Recently we received the first pre-production footballs for inspection. These pictures should give you a better idea of what kind of quality and finish you can expect from the HD Blower kit.
Here is a recent dyno graph of a the kit on a stock 103 engine.
1)The 103 motor is completely stock!…stock exhaust, stock cams.
2) We still have not finalized the last few parts of the design for this kit…for example the ‘football’ is only a prototype design, we expect better results from the new/final football design and air cleaner set-up.
3) We can still spin the charger faster for greater gains, but this will require lowering the bikes redline.
Here are a few things to note when watching the video:
THE SOUND: The blower kit is virtually silent. The whirring sound you hear is the sound of the dyno rollers and not the supercharger. Except for sounding more powerful, the classic potato-potato Harley sound remains unchanged.
LEG POSITION: The riders leg position is the same as on a factory bike with plenty of leg to supercharger clearance.
The HD Blower football sits slightly higher than the stock air cleaner cover and only sticks out an additional 1/4″ from the stock position. The final production units will be heat insulated and aircooled so cant burn your thigh on the football.
The main unit below the football sticks out from the side of the bike by less than 1″, allowing the riders leg to remain in the stock riding position.
People have been asking us how much power the kit makes and in all honesty we really don’t know at this point because we are still in the middle of trying different configurations to come up with the most rideable power curve. In its unrestricted configuration, we estimate the kit should be able to make over 135hp to the wheels (at approximately 13psi of boost) but will probably require certain supporting mods. As a point of reference a stock 103ci makes about 65hp and a stock 96ci makes about 57hp to the wheels. Now before you go busting out your imaginary rulers and start measuring the horsepower of your fantasy blower/turbo set-ups, let us just say…we are not interested in chasing after the title of making the most horsepower. If we wanted to cater to the peak-horsepower-chasing dyno-weenies, we would have built a refrigerator sized blower kit large enough to house the biggest possible supercharger, 2 nitrous bottles, a case of beer, and a pint of nitro. Continue reading
Can you believe the main picture of the supercharger kit is a computer generated rendering? Don’t worry, this blower kit is in pre-production functional prototype testing phase, and isn’t just some fantasy digital graphics art project. HDBlower is only made possible with the right blend of old school mechnical know-how and new school wiz-bang computer technologies. We’ll show you more of the tools of our trade in later posts.
Don’t let the simple and elegant shape and design of our ‘football’ fool you. Underneath that slim and pretty cover is a monster of engineering. All the factory football has to do is house the air cleaner. Our football, which is the same width side-to-side but slightly narrower top-to-bottom, must to house the aircleaner, the ‘turtle’ (pressure side intake transfer manifold), and a custom pressure bypass valve.
If you look at the Rotrex Technical Datasheet, you will see that peak input shaft speeds for the superchargers range from 11,840rpm to 15,900rpm. In order for us to be able to have sufficient flexibility and options for tuning the shape of the boost and power curve, we needed to, at the bare minimum, be able to spin the charger at its peak input speed at redline. Using a just a single stage to step-up the engine rpm, the highest input shaft speed you can achieve is approximately 10,000rpm at redline; well shy of the limits of the charger. To solve this under spinning issue, we use a two stage system to step up the input RPMs. Continue reading
When we set out to design our supercharger system, not only did it need to have a compact form factor, but it needed to be beautiful. We looked at other superchargers and they all looked pretty cool, but nothing struck us as being very beautiful. Though beauty is subjective to a certain degree, there are a few rules of beauty that tend to hold true. These basic rules are: Symmetry, Size & Proportions, Lines, Curves, & Details. Continue reading
We felt one of the keys to making the ultimate supercharger kit was making things as compact as possible. Harley Davidson went to great lengths to design beautiful engines and motorcycles. The last thing we wanted to do was ruin the look of someone’s bike by hanging some bulky-square-edged robot-looking supercharger system off the Continue reading