Title: 
Tips on choosing appropriate dynamometers

Word Count:
437

Summary:
In order to set up a drag car or bike for peak performance, using loads of boost / nitrous or other modifications, the best thing to have is a suitable inertial chassis dynamometer. It needs to have big diameter clean drums, with a very good grip. Dual rollers are not appropriate in this case, so don’t use them!


Keywords:
dynamometers, dyna, inertial dynamometers


Article Body:
In order to set up a drag car or bike for peak performance, using loads of boost / nitrous or other modifications, the best thing to have is a suitable inertial chassis dynamometer. It needs to have big diameter clean drums, with a very good grip. Dual rollers are not appropriate in this case, so don’t use them! 

The dynamometer should have powerful fans and airflow and an experienced operator. 

A braked system is simply unsuitable for an application like this.  The dyno itself, along with plug readings, and experience would be the best way to set the car / bike up.  Gas analyzers are useless in these situations.
If your aim is to set up a stock or mildly tuned cars / bikes fuel injection system, or set up a carburetor systems jetting or ignition properly, you should find a decent braked system, maybe with twin rollers and with a good gas analyzer.   
This is the best way to set up this kind of vehicles.

You should use this kind of dyno tools if you are working on stock or mildly tuned car for fault finding, or for a health check.
To obtain the accurate power curve picture of a vehicle, you should put on an inertial dynamometer. 

In order to buy one for yourself, you should consider the above, decide what kind of work you mainly want your dyno for, and choose accordingly. 

An important thing to remember is that inertial dynos may be cheaper, but they are more difficult to control (you cannot hold RPM steady on an inertial dynamometer).

However, no matter what type of dynamometer you select, controlling the test conditions is vital to getting usable data. It's not enough for the dynamometer equipment itself to be accurate; you have to know that the engine's output is not being skewed by improper dynamometer procedures.
In order to prepare your car or bike for a dynamometer testing session, you should consider some of the following:

You should check oil level, being careful not to overfill. If necessary, perform oil and filter change first. 
Make sure the air filter is clean.
Check coolant level.
Check for coolant leaks visually
Check tires for correct pressures and healthy condition, especially if it’s a seriously powerful vehicle, as grip may be a problem.
Add enough fuel.
If you use nitrous, water injection, make sure these are all topped up!
Make sure it has correctly gapped healthy plugs.

That's basically all you need to do. Dynamometer testing is no worse for your car than a bit of fast motorway driving, and in some cases even safer for your engine!