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Secrets of Tuning: Inside a dyno cell

September 17, 2019


Having been a top-flight UK tuning company since 1984 Torque Developments International continues to provide successful engineering solutions to motorsport for the professional cars enthusiast. My name is Sam Borgman I’m the technical director here I have over 10,000 hours of real-world experience here in the dyno cell. I’m going to give you a glimpse at how we work here on a day to day basis in the world professional tuning. Hi welcome back I’m Sam from Torque Developments let me show you around our dyno cell. Welcome to our dyno cell we’re going to have a look around the whole room but the first thing I want to show you is the dyno itself. This is our Rototest VPA-9 this is what we call, a hub mounted dyno it replaces the road wheel on the vehicle that we’re testing, this bolts directly to the vehicle’s hub flange this removes the tire from any kind of measurement or stress situation and we’re metal-on-metal straight to the car which means that as long as the clutch isn’t slipping in the drivetrain we’re metal-on-metal all the way to the engines crankshaft that’s really important. The actual dyno itself is a fluid brake dyno what that means is that we can brake the axle on the car that doesn’t mean break it as in damage it but we can slow it down, we can control the speed of the axle. We do this by having a large hydraulic pump here driven by the cars axle and the hydraulic pump is pushing oil through a controlled solenoid this is like a tap and we can turn it on or we can turn it off electrically when we turn the tap off we produce a big resistance in the oil pump here and it controls the speed of the axle on the vehicle. The whole time that we’re controlling the speed of the axle we are also measuring the amount of twisting force that’s coming out of the axle now that’s done by this whole pump assembly being able to leverage itself onto a deformable strain gauge down here which we calibrate the beginning of every week with dead weights The more this strain gauge bends the more twisting force is being applied by the vehicles axle. it’s this direct measurement of axle torque and a very accurate measure of the axle speed that allows us to calculate precisely how much power is coming out of a vehicle axle at any one given moment in time. So the dyno gives us the ability to control the vehicle in terms of its speed and to measure precisely what the output is. So our oil pump dyno here pumps high-pressure hot oil forward in the dyno cell and into this assembly here the first law of thermodynamics tells us we can’t create or destroy energy and the dyno system is no exception to that rule. If we were absorbing a thousand kilowatts from a high power car on the back axle we have to turn that thousand kilowatts of energy into heat in that oil comes forward in the cell in the back of this unit six large setrab oil coolers that hot oil is sent through those oil coolers and then through two hydraulic motors which run these fans in counter rotation drawing air through the setrab oil coolers full of hot oil and throwing the hot air out here into the room. The idea here is it cools the oil down and the cooler heads back at low pressure to our dyno system ready to do more load absorbing at the back of the vehicle. Now we’re throwing reasonably warm air into the room here but want to control the temperature of our dyno cell we want to cool any vehicle we might have in here testing so it’s really important we have an amazing flow of air into the cell. This is the output nozzle from a large axial fan mounted to the back wall of our building in a whole array of flow conditioning vents. I can control the speed of this front fan and with it absolutely flat out we can get about 130-135 mph of air speed here on this nozzle. This air flows backwards across our test car hopefully cools the car adequately more than enough and then we have two computer-controlled fans in the roof of the cell at the back here. Now these go faster or slower as is necessary to keep the pressure in the room here at ambient. We don’t want to run our test cell at above ambient pressure or below ambient pressure for fear it might influence the engine management calibration work that we’re doing in here. Once the back axle has absorbed all of the power and it’s taking its rotational speed measurements and is taking its continual talk measurements we’ve got flowing data coming back to our data acquisition system. The data acquisition system is also the control system. So not only are we reading the axles talk and it’s rotational speed constantly at high speed here we’re also controlling the speed target for the back axle I can speed the engine up or slow the engine down here. We also have a 16 other channels of data that we can feed into the system and take readings of pressures and temperatures and any other type of data that we can encode and make it synchronous with the torque and the speed readings they’re coming off the back axle of the vehicle the front axle all four axles because we can cater to four wheel drives here. As we come towards the back of the cell you’ll notice that the walls here all over the cell on the ceiling are made of a stainless steel mesh if stainless steel mesh hides behind it layers and layers of flame-retardant, sound-deadening for a couple of reasons primarily there are occasionally thermal events in here that some people might call “fires” in we need to be equipped for dealing with that but a bigger more operational professional operational reason is to quell the noise that leaks from our test cell very often we’re working with vehicles that are running unsilenced and sometimes very very loud engines indeed Formula one cars regular place here so we need to be able to use the phones elsewhere in the building while we’re testing a Formula One car in here. Here we have lastly but certainly not least, exhaust extraction. there’s another 8,000 cubic feet of air per minute going out of our exhaust extractors here to keep the cell free of exhaust gases from the engine. It might sound over the top but exhaust gases from petrol engines even normal pump petrol are extremely poisonous and they’re poisonous in a way that’s not immediately obvious to the person who’s being poisoned carbon monoxide causes you to drown and if you don’t realise until you lose consciousness worse than that number of cars that were asked to tune in here running on very, very highly, volatile and quite exotic based fuels some of these race fuels have really quite dangerous additives in them we don’t want to be breathing them at all! Really important part of our dyno cell. Thank you for allowing us to show you around dyno cell today. For our next video we’re going to get a car in here hook it into the dyno instrumented up with all of the measurement equipment that we have here and get tuning so you can see it’s using all of the equipment we’ve shown you in the dyno cell here today. for more information about Torque Developments and the Academy of Motorsports Sciences please click on the links in the description below. and to make sure you don’t miss any of our upcoming videos please click the subscribe link.

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