Our Superflow SF 902 Engine Dynamometer
The answer is: development and accuracy.
An engine dyno allows you to take the power straight from the flywheel; it is the most accurate way to measure engine power. You can see small changes in torque/bhp and it is the only way to really test for small changes in power.
Then there is the convenience of just having to work with the engine, it can sit on a dyno for weeks and not be in the way. You have unlimited access to change things like exhaust lengths and you can set up the engine to monitor just about everything from air flow to exhaust gas temperatures, even on individual cylinders. The kit we are now installing can even measure ring blow-by and tell you when an engine is run-in – or worn out!
We originally bought our dyno second-hand and it was a Superflow SF 901. It came with a mass of monitoring kit but most of it was analogue. Being an electronics based company we felt that we could do a lot more integration with our ECU systems if we had the full digital kit. For that reason we upgraded the dyno to a Superflow 902. At the same time we added a temperature compensated load cell and a new, faster, control valve to the dyno absorption unit.
At the time of writing we are installing the extraction system which will have the capability of changing the air in the test cell ten times a minute. If an engine is breathing its own fumes the power will neither be consistent or accurate. All this kit is a long way from the first engine Dyno's that I used, Heenan units that leaked copious amounts of water to the extent that most testing was done in Wellington boots! Okay, what we have now is no million pound test facility but it’s as accurate as we can get it and the plan is to use it to test Ecu's and develop performance engine components. It will not be used to map customer’s engines; we see it as an R & D facility and nothing else – at the moment.