Hub Dyno Test Cell Facility
Our purpose built facility is ideal for OEM’s, Race Teams and R&D specialists
The facility is suited to incar engine performance, calibration and validation testing – Engine development testing & Powertrain testing.
Nicholson McLaren’s bespoke hub dyno cell can facilitate:
- Automotive Engine & Powertrain Testing
- Road & Race Cars – Front/Rear Wheel Drive & 4 x 4
- Electric, Hybrid, Petrol, Diesel
- Air Cooled or Liquid Cooled
- Up to 1000 HP
Customer engineers can be accommodated on site with a dedicated office facility, ensuring a discrete and confidential operation away from prying eyes. The test cell is available for team hire.
Whether you are developing electric vehicles, hybrid vehicles, an automotive development company, a race team, or an oem needing independent torque vectoring on 2 and 4wd vehicles we have solutions that meet your needs with our 2wd and 4wd chassis dynamometer.
Our dynamometer which is manufactured by Dynapack™ direct couples to the wheel hubs and applies a precisely controlled hydraulic load. This method of direct coupling plus its built-in strength means the Dynapack™ is always in control of the vehicle.
Controlling a powerful car on a roller dyno can sometimes be a daunting task. With Dynapack™ you have TOTAL CONTROL of the vehicle, with no wheel slip due to its direct coupled design. With that there is less inertia to mask the results, giving you greatly improved sensitivity, repeatability and significantly reduced time spent tuning and mapping!
With the power of the Dynapack™ literally at your fingertips, you have complete control over the test and the demands placed on the vehicle. Flexible data presentation and analysis is available direct from the Dynapack™ in seconds.
How is the dynapack different?
THE MOST OBVIOUS DIFFERENCE IS THE ELIMINATION OF THE TYRE TO ROLLER INTERFACE THAT EXISTS WITH A CONVENTIONAL ROLLER DYNO.
The Dynapack™ eliminates this variable by using a hub adapter that provides a direct coupling to the Power Absorption Units. There can be no tyre slip, no rolling resistance, and no chance of the vehicle coming off of the dyno at high speeds. Notice that we call this a variable. Sometimes it may be a problem area, other times it may not. Tyre temperature, pressure, traction, etc, are all variables that can change – not only from run to run, but during the run as well.
Throw an unknown variable like this into the equation and your data has now become subject to a potentially high margin of error. It is obviously better if these variables could be eliminated – which is exactly what we have. There are other associated problems with the roller method as well. Take tie-down straps for example, most roller dyno’s use ratcheting tie-down straps to attempt to hold the vehicle in position while being tested. If the straps are cinched down tightly, the tyre has becomes loaded even further, in an unpredictable manner.
While this may be good for enhancing traction, it changes the rolling resistance of the tyre – skewing the data further. Since these tie-down straps aren’t perfect, the vehicle squirms around on the rollers – dramatically changing the tyre drag during the run. If the vehicle is tested in two different sessions, the straps can’t be set exactly the same way twice in a row. Again, the data will be inconsistent.
We have heard of cases where the ratcheting tie-down straps were loosened by two clicks and the measured power increased by ten horsepower. What if the straps stretch – either from run to run, or during the run itself? Wouldn’t it be great if all of these problems could disappear? With a Dynapack™, they were never there in the first place.
ANOTHER MAJOR DIFFERENCE IS THE EFFECT OF INERTIA.
Street wheels and tyres spinning at high RPM have a large amount of inertia. A large steel drum spinning at the same ground speed has much more inertia. What you end up with is a giant, heavy flywheel attached to your engine. The inertia is such that just trying to accelerate the mass of the roller is a substantial load for the engine. That is the principle that some roller dyno’s (or inertia dyno’s as they are also called) operate on. Accelerate a known mass to a measured speed over a given time and it can be calculated to equal a certain amount of power. There is nothing wrong with this theory, but like many theories, its application in the real world can be troublesome.
How do you think your measurements will be effected when subjected to this large heavy flywheel phenomenon? Will small fluctuations be noticeable? In a word, no, the flywheel effect tends to take small rapid variations and smooth them right out – as energy that should be going into the dyno is being wasted trying to accelerate a large lump of steel.
This is great if you want your power curve to look like a smooth pretty line, but it doesn’t give you much insight into what is really occurring. What if you eliminated this flywheel effect? The inertia of a Dynapack is practically zero!
The dynapack controls the car, the theory of operation and the implementation of that theory are actually fairly simple. it took several years and a lot of hard work to make it as simple as it is today.
The hubs of the vehicle are directly attached to hydraulic pumps. We can apply a variable but precise load with all of the potential holding power that hydraulics possess. The wheels are removed from the vehicle. Our variable fit hub adaptors are bolted to the vehicles axle. The hub adaptor is then directly attached to a hydraulic absorption unit. We can apply a variable but precise load to the axle(s) of the vehicle.
Simultaneously, we are monitoring pressures and measuring hub RPM, so we can determine the amount of work being performed. It sounds easy until you realise that all of these calculations are very complex and are happening very quickly. Add to this, all of the data logging functions and real-time full-colour graphics that are also being calculated and you begin to realize that what appears to be simple is actually very complex…being the best is never easy.
Traditionally, most serious engine builders have thought that chassis dynamometers were inferior to the results you could obtain from a quality engine dyno. Having effectively attached engine dyno style load cells to the axles, we now have the type of precision and repeatability normally associated with an engine dyno, but with the convenience and benefit of having the engine operate in its natural environment.
Because we need a precise and powerful loading device, we use hydraulics. We do not use inertia, we do not use eddy currents, air, or friction. Because of the incredible holding power hydraulics offer, we have TOTAL control of the axle speed. Literally
Want to hold a steady RPM under high power? We can hold an exact axle RPM (+/- one RPM) at any power level – all the way up to the full maximum rated torque capacity of the dyno, CONTINUOUSLY – for as long as you like. If the software allowed it, we could stop the engine within one revolution of the axle – even if the engine is at full throttle at its maximum torque level. Obviously you would not want to do this, and our software prevents it, but it does give you an idea of just how much power and control we have over the axle speed.
The Dynapack controls the car! We control the axle speed and rate of acceleration at all times, it allows you to see exactly what the vehicle is doing at any given point in time and RPM of the completed run.
Because we aren’t limited by the capabilities of eddy current brakes and similar devices, we open up a whole new world of tuning possibilities. Times change and technology evolves. What was once “industry standard” is now yesterday’s technology.