Bapro Chassis Dynamometers

            		             

Hub Dynamometers

            
Type of power measurement Crankshaft (engine) power, the unique absolute value to trust on. Wheel power, totally unreliable and unrepeatable
Operations to restrain the vehicle Straps. To lift the car and remove all the wheels, it takes time!
Tools needed in addition Nothing, everything is included in the dynamometer. Lifter and tools for wheels’ disassembly. Newest cars always need special tools because of the security nuts!
Parts subject to fast wear Nothing. For example: our rollers do not wear at all, for all the life of the dynamometer. Hub splines wear fast and cost a lot.
What to do in case of wheels with aggressive toe and camber angles? Align the car as usual and strap it as usual. Move the pods manually in two directions, it takes time and it is a difficult operation!
Issues on small capacity engines and 4wd cars? Absolutely not. Sometimes yes, the control of the dynamometer isn’t stable. There is the risk to break gearboxes.
Is water needed? Absolutely not. Yes, in case of hub dyno equipped with water brakes. For Dynapack you need a 600-liter reservoir, which is suitable only to 400HP cars. Instead, you need to add fresh water!
Does the hub dynamometers need less workshop’s space compared to a chassis dynamometer? No. The only advantage is that you can move the pods around, for example storing them somewhere, so clearing your test area when not used. But you are supposed to use them every day! Right?
Moreover, the pods are heavy, big, and they need even more space in width if compared to a chassis dynamometer because there is one brake for each wheel.
If we talk about space in length, in case of a 4wd hub dynamometer (4 pods) the space needed is the same of a chassis dynamometer.
In case of a 2wd hub dynamometer (2 pods), a well installed and positioned chassis dynamometer will occupy the same space of a 2wd hub dynamometer.
What about the huge levels of handled torque claimed by hub dynamometers? The hub dynamometer has the disadvantage of directly having to deal with the torque delivered at the wheels of the car because, being the tire absent, the torque reduction made by the tire itself isn’t present. In a chassis dynamometer the tire applies a torque reduction to the rollers of the dynamometer. This is why a hub dynamometer MUST always be equipped with a very big (and greedy for electricity!) eddy current brake.