Live Data XiDash In-Car Dash

XiDash On-Road Dyno Testing

XiTek XiDash Road Dyno feature (from hereon abbreviated to XiRD) allows real life performance testing of any manual transmission SUBARU vehicle supported by XiDash.

In addition, due to the way the XiRD does its calculations, it is unaffected by any piggyback ECUs or speed delimiter modules.

How it works


Using XiDash Road Dyno

Getting Accurate Results


Test Gear

It is absolutely essential that the correct test gear is chosen in order to get accurate results. Using 'Test Gear', you must select the gear in which the test was performed.

Tyres & Gearbox

Since XiRD uses engine RPM data to calculate vehicle performance, the characteristics of the gearbox & tyres must be specified so that XiRD can translate measured engine RPM into the correct vehicle speed. Tyre data is easy to ascertain. Simply look at the tyres on your car - they will have their dimensions printed on the side wall. Gearbox data, unless you've been doing serious modifications to your car, will be the same for all cars of a particular model - simply select the correct model from the list. If you have modified your car's gearbox, then you are the only one who should know this information!

Vehicle Mass

In order to calculate the power & torque that the engine is generating based on this speed data, XiRD must also know the mass of the car - it is important to get this figure accurate, since the calculated power will vary in proportion to the mass entered. The mass specified should be the current mass of the vehicle at the time of the test.

The following variables will affect the current vehicle mass:

The book kerb weight should not be used. Get your vehicle weighed with a known amount of fuel in the tank. This may be done at a weighing bridge or by using corner weight scales for a really accurate reading.

Overestimating the vehicle mass will give a power figure that is too high. Underestimating the vehicle mass will do the opposite.


XiRD takes into account aerodynamic drag when calculating engine performance. Vehicle drag co-efficient and frontal area are the parameters required to calculate power lost to aerodynamic drag. Whilst important for accurate power calculations, these vehicle characteristics are far less important to measurement accuracy than the vehicle mass. Aerodynamic drag is quite small in 2nd & 3rd gear and so inaccuracies in these figures will only result in a small (2 or 3 BHP) error in calculated power. If power tests are performed in higher gears e.g. 4th, 5th or 6th, then the importance of these values becomes much greater. In the absence of definitive data, use a frontal area of 2.2 sqm and a drag co-efficient of 0.35.

Rev Limit

The ECU's rev limit is only relevant when calculating the maximum speed possible in each gear. It is not used for any other performance calculations. Unless your car's ECU has been modified, then simply select the rev limit matching the model of your car.

Comparison of Road Dyno & Chassis Dyno Power Testing

Disclaimer & Safety Considerations


Используются технологии uCoz