There are many, even among those in the industry, who do not know what the flux bank is or what it is for. Not to mention most private individuals and tuning enthusiasts. Well then, let’s start at the beginning! As we all know one of the most profitable ways to increase the power output of an engine is to introduce more air into the cylinders. After that you adjust the carburetion by increasing the gasoline in the right proportion of the air, and that’s it.
Very simple to say true … but unfortunately to do much less. Leaving aside the replacement of the camshaft and the replacement of the air filter, things that are now the order of the day, let us turn to the machining of the head and its ducts. In most cases, valves are enlarged, ducts are polished, passages are narrowed, etc. But it’s difficult to quantify the benefit done until after the engine is reassembled. Well, if we got it right we gained a few horsepower here, lost a few things there, etc. Even very good workmanship done by very skilled hands will only be able to be evaluated at start-up and after the engine has been tested, either on the dyno, or on the road.
After that, if something doesn’t add up, down everything again, and look for what it is that made us lose what we didn’t want. The most common causes are air velocities, which as a result of incorrect or exaggerated machining of the ducts and valve seats drop considerably so that air can no longer enter beyond a certain limit. What to look for in a duct head machining are the greatest possible air flow associated with a high inlet velocity. All the research done in recent years by car and engine manufacturers has been done more or less well along these lines.
See variable timing, variable resonance ducts, etc. Well, this is where the fluxing bench comes in, which is responsible for measuring all those fundamental quantities we have been talking about. It allows us to check flow rate, speed, temperature in the different configurations of use. It will be able to point out to us whether the lift of a cammes is exaggerated, whether it is too low, whether the profile of a valve seat goes better at x degrees rather than at y.
To summarize, the flow bench allows us to make all those fundamental checks of engine fluid dynamics, allowing us to figure out which way to go without compromising what we would not have wanted.