For many this holds a vision of taking a Car to the “shop” and having them strap it to some magical machine. This turns it into a power monster with a thrifty appetite for fuel. Nothing could be further from the truth.
What is a Dyno ?
Simple, it is a tool to measure power output of an Engine.
You have Engine Dyno’s that measure Power at the crank. This is the best for Engine development, but necessitates rather long set-up times.
Then you get Dyno’s that measure power at the driven wheels.
There are Dyno’s where you accelerate a given mass through the rev range- these take the time taken from rev point to next rev point and calculate power.
Then you have Dyno’s that have a “brake” on them, to hold the engine at a particular RPM and power point, that measures Power.
The brakes are either water or eddy current (look it up under Foucault- be careful not to verbalise that name) brakes. In Noah’s times you also got leather belts with weights on them to brake pulleys.
I needed a braking Dyno, as most cars are fuel injected and I can improve my previous tuning efforts on Carburetted cars. Therefore I decided to do is get a MAHA eddy current wheel brake, with a Sun 4 Channel Exhaust gas analyser. These 2 tools can “talk” to each other and are extremely robust being designed for testing stations where they are constantly (ab)used. Furthermore it can:
Correct power to crank output, sea level and DIN norm.
Measure Oil, Exhaust & Intake air Temp
Pressures (Barometric, Boost, Oil, Fuel etc)
Correlate between RPM and exact road vs. speedometer speed
Do continuous, discrete, constant (speed, RPM, traction) power measurements
Simulate driving conditions
Record back power measurements to test different products.
A Dynotune entails strapping your vehicle (Bikes also) to a testbed and then do a Power run where the power gets measured from idle to redline. This should be stored in a Databank for future use. Then we would concentrate on where you would envisage the problem to be and run it at that speed and load to sort out the problem. At each speed/load point it automatically measures the Exhaust gasses, so we can tune your Fuel injection/carb ignition to be spot-on. At the end we can do another power run, superimpose it on the first, to check our work if it actually made a difference.
I believe in tools and have invested in Data logging equipment to run on the track or Dyno making fine-tuning far easier.
Here comes the crunch, we are not a repair shop and will therefore only perfect EFI vehicles that have no problems. I don’t mind helping workshops or selling parts to help somebody out of their “penarie”. But I won’t do faultfinding ! If you know that your “computer box” is stuffed and you have found out why, then I can sell or install a aftermarket ECU on your vehicle + tune it on the Dyno to make it fly again. Cost 2500 to 6000+ N$.
As you know I am shop that tries to improve the vehicles efficiency. The UNICHIP is a great aid in that by perfecting the Fuel and spark lines to your specific vehicle. Cost 2 to 2500 N$.
If you have a Weber, Holley, Edelbrock carburetted vehicle, we can fine-tune it for +- 1000 N$.
In the past we would do our modifications and then take the car to Bosch (they only have an inertia Dyno) to set up the Carburettor. On fuel-injected cars we tried to wiggle the mixture with an adjustable fuel pressure regulator and resistors in the metering- far from exact but it did satisfy the customer. Now I can perfectly tune the engine management for that particular vehicle and its modifications. More power and a definite decrease in fuel consumption.
Lastly you must be aware that a Dyno can be gyppoed to show you an impressive reading.
Also there are many different norms, so be sure if comparing that both Dyno’s have been assized to give reading using the same Norm taking into effect outside factors, such as Oil/ Air temperature, Barometric pressure etc.
What you should ask the Dyno operator:
What additional equipment is used to accompany the Dyno ?
When was the Dyno last calibrated and to what norm ?
How constant can it hold power (0.5 Kw is normal) ?
Can you get a normed/repeatable power reading i.e. Din at sea level 25 C ?
How fine is its power measurement (switching the headlights on should show a drop in power) ?
Can he store your Data for future use ?
Tell him what is not standard on the vehicle.
Tell him what you want done and what you expect at the outcome. Maybe even how much you are prepared to spend.
What you MUST be aware of, that the car will be tested to maximum power, so if it is “sick” tell the operator. No Dyno operator will take any responsibility over the well being of your Engine, gearbox or drivetrain. Do not have a vehicle strapped on the Dyno with unsafe modifications, such as rims that are held on by to short studs (don’t laugh I have seen it happen and the result- a written of Camaro and 40 000 Dollars of Dyno room damage). Also have the fuel tank at least 3/4 full.