What is volumetric efficiency? In simple terms, volumetric efficiency is how filled the cylinder is, (immediately before the compression stroke starts), compared to the actual capacity of the cylinder.. In other words, how easy is it for the air to enter the engine. The better the VE the more power the engine has * Volumetric efficiency calculator uses Volumetric efficiency of a pump= (Actual discharge of a pump/Theoretical discharge of a pump)*100 to calculate the Volumetric efficiency of a pump*, The Volumetric efficiency formula is defined as 100 times of the ratio of actual discharge of a pump to the theoretical discharge

Volumetric Efficiency (VE) Test Procedure While graphing the PIDs, accelerate at wide-open-throttle (WOT) to near redline in first or second gear. Capture the movie or screen on the Scan Tool and return to the shop to enter the peak RPM and MAF values into the VE calculator along with intake air temperature, altitude, and engine displacement * Volumetric Efficiency of Pump or Fan Calculator Volumetric Efficiency of Pump or Fan Calculator Volumetric efficiency (η v) defines the ratio of fluid delivered by a piston pump per stroke to the displacement volume of the piston*. It can be increased to above 100 percentage for improved performance

- The higher the volumetric efficiency the higher the volume of intake air in the engine. In case of indirect fuel injection engines (mainly gasoline) the intake air is mixed with fuel. Since the amount of fuel is relatively small (ratio 1:14.7), compared with the amount of air, we can neglect the fuel mass for volumetric efficiency calculation
- Description Test your mass air flow (MAF) sensor, and check your vehicle's volumetric efficiency (VE) with this calculator. This app is for professional automotive technicians, but can also be used by DIY-er's who have their own automotive scan tool
- ute CFM, cubic inch displacement CID, and revolumtion per
- Volumetric efficiency (VE) is the actual amount of air flowing through an engine, compared to its theoretical maximum. Basically, it is a measure of how full the cylinders are. VE is expressed as a percentage. An engine operating at 100% VE is using all of its volumetric capacity
- ute. The efficiency is the volumetric efficiency of the motor. Most engines have a volumetric efficiency of about 85%, or.85

* The MASS of ingested air is directly proportional to (a) the air density and (b) the volumetric efficiency*. There is a remarkable similarity in shape between an engine's VE curve and its torque curve. For contemporary naturally-aspirated, two-valve-per-cylinder, pushrod-engine technology, a VE over 95% is excellent, and 100% is achievable, but. Volumetric Efficiency Calculator - Diagnostic Network NASTF is a cooperative effort among the automotive service industry, the equipment and tool industry and OEMs to ensure that independent automotive service professionals have the information, training, and tools needed to properly diagnose and repair today's high tech vehicles

This video explains how to create your own volumetric efficiency calculator for a gasoline engine that has a mass airflow sensor. It includes the formulas a.. Volumetric Efficiency on a Forced Induction Engines. In last August GEARS article I suggested that a volumetric efficiency (VE) measurement could be a valuable diagnostic tool for testing MAF sensors as well as other engine breathing issues. This calculation helps level the playing field when specifications are absent. These two. volumetric efficiency is the ratio of the volume of air/charge drawn into the cylinder/s during the suction stroke to the total displacement of all the cylinder/s at the atmospheric pressure ⓘ Volumetric Efficiency when Compression and Pressure Ratio are Given [VE

- Use this tool to test MAF sensors and check for engine breathing problems.To access the calculator at www.tat.net.a
- ed by dividing the actual flow delivered by a pump at a given pressure by its theoretical flow. Theoretical flow is calculated by multiplying the pump's displacement per revolution by its driven speed
- e your engine's intake volume requirements. Enter the engine's displacement, Volumetric Efficiency, and its redline. The calculator will tell you the cfm range you need. VE is affected by intake type, camshaft grind and type, boost, and many other factors
- Test your mass air flow (MAF) sensor, and check your vehicle's volumetric efficiency (VE) with this calculator. This app is for professional automotive technicians, but can also be used by DIY-er's..

Volumetric efficiency is the ratio of actual volumetric flow at inlet temperature and pressure conditions to piston displacement. It is given by: (11-7) E v = 96 − R − C[(R1 / k)Zs Zd − 1 The Volumetric Efficiency calculator determines the engine's ability to pump air. Measuring VE helps you diagnose restricted intake systems, restricted exhaust systems, air metering problems, and/or mass airflow sensor issues. Questionable values are highlighted in red. Calculator for Fuel Requirement . The fuel requirement calculation is. The volumetric weight of a shipment is a calculation that reflects the density of a package. A less dense item generally occupies more volume of space, in comparison to its actual weight. The volumetric or dimensional weight is calculated and compared with the actual weight for each piece in the shipment to ascertain which is greater; the. Note: This Plunger Pump Flow Calculator assumes 100% volumetric efficiency, meaning it does not consider any slip or back flow of fluid through the valves of the pumps, and assumes that there is no leakage through the packing or any other part of the fluid chamber. If more in depth calculations are needed to calculate the volumetric efficiency of a plunger pump, contact the Power Zone. The theoretical volumetric flow rate (Q th) is more or less chosen arbitrarily, based on atmospheric air density.Because air is compressible, a volume does not limit the quantity of air that can be pushed in, especially when gas dynamics are considered.. So volumetric efficiency is not a true «performance» criteria for an engine because what counts is the air mass flow rate

VE Calculator for vehicle driveability diagnosis. Calculate expected vehicle engine load and volumetric efficiency from RPM, Mass Air Flow, Intake Air Temperature, and barometric pressure. From the.. Supercharger Boost Calculator ~ Input the Blower Belt Ratio, Engine Volumetric Efficiency Percentage, the Blower Volumetric Efficiency Percentage, the Engine Displacement, Blower Displacement and the Barometric Pressure and the Supercharger Boost Calculator will give you the Blower Boost. And don't forget you can choose between English and. A few years ago, I obtained an OBDII scan tool/dynamometer simulation/calculation program that can graph volumetric efficiency (VE) over rpms.AdvertisementClick Here to Read MoreAdvertisement Using real world vehicles, and no useful instructions, I devised a test sequence that allows a technician to see things another way. What is Volumetric Efficiency

- Lesser the volumetric efficiency less is the capacity of the compressor. The volumetric efficiency of the compressor also depends on the compressor ratio. If the difference between the suction and the discharge pressure is higher, the refrigerant will remain trapped inside the clearance volume for longer time and prevent the opening of the.
- A volumetric efficiency test can back up your hunch with hard numbers. The engine really has a simple function-to pump air. If an engine were a perfect pump with no inlet or outlet restriction, no compression or power stroke and no leakage, it would displace the same amount of air as its volume every revolution
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- Typically intercoolers are used to drop compressed air discharge temperartures. A typical entry is 130. To run calculations on this use our Intercooler Calculator. Volumetric Efficiency: Volumetric efficiency can be above or below 1.0 A typical entry might be .95: Peak RPM: Enter peak RPM: Displacement in Cubic Inches: Engine displacement in.
- Learn more about Engine Air Amount Calculator. Home › Forced Induction › Engine Air Amount Calculator. Calculate Engine Air Amount Volumetric Efficiency (between 75-100%): Boost Pressure (Bar): Results: Pressure Ratio (used in turbo maps) = 1.7 Amount of air in CFM = 302.724
- Free Volumetric Efficiency Calculator Posted to Technical Tips Forum on 8/2/2017 5 Replies We have a new FREE Volumetric Efficiency Calculator that is available to everyone

Volumetric efficiency, or VE, is a measurement of how well a pump can move a liquid or gas compared to its physical limitations. If one were to perform an internet search, the results would include things like oil drilling platforms, hydraulic rams and more VE = volumetric efficiency 2 valve engines 85% 4 valve engines 90% ported 95% race heads like whoa 103% these are just estimated numbers, but should get you pretty close to what you need. Pr is taken from the calculation we did earlier Drag Racing Calculators,Calculators to find 1/4 mile ET and MPH, CID,Piston Speed,gear ratio,carburetor size,margin of victory,Engine calculator, Calculates relative horsepower, air density, density altitude, virtual temperature, actual air pressure, vapor pressure and dyno correction factor and more Volumetric Efficiency. Volumetric Efficiency. Application: GM V8 based vehicles. Basic terminology. Tables and programs to use: VCM Scanner Histogram: This is a graphical tool used to record the LTFT , STFT process as it happens live. This program will be you basis for where, when and how much to change on the VE table

- The swept volume of one piston can be calculated the following way. Not all the cylinder volume can be used for the compression as there is always the clearance at the end of the cylinder that remains with some air inside. This phenomena can be quantified by defining the volumetric efficiency of the compresso
- Drag Race Dyno ~ This calculator will allow you to figure out your horsepower based on your ET times in either the 1/4 mile or 1/8 mile. It's based on the Track Length, Finish Speed and Vehicle Weight. Port Flow Efficiency Calculator ~ The Port Flow Effciency calculator will allow you to figure out the efficiency of your ports based on Test Pressure, Number of Valves, Valve Diameter, Valve.
- where R is 8.314 J/°K/mole and the average molecular mass of air (MM) is 28.97 g/mole. Note that in the above formula the volumetric efficiency of the engine is measured in percent and the displacement is in liters. Once we have MAF integrated over time, we can calculate fuel flow using a specific air/fuel mixing ratio (A/F)

Volumetric Efficiency (VE) Operation - The option of a Volumetric Efficiency based tuning strategy is now optional. This changes the Base Fuel Table units from pounds/hour of fuel to VE%. VE fueling calculations are calculated from the following inputs: - Engine Displacement (NOTE: Make sure this is input properly in the Engine Parameters!! volumetric efficiency: CFM = engine air flow rate - cubic feet per minute: CID = engine displacement, size or volume - cubic inches: RPM = engine speed - revolutions per minute: NOC = number of cylinders: BORE = length: STROKE = length: HGV = head gasket volume: HGCT = head gasket compressed thickness: PDV = piston deck volume: DPD = deck to. Volumetric Weight (Kilograms) = [Width x Length x Height] / 6000 (Centimetres) OR; Volumetric Weight (Kilograms) = [Width x Length x Height] / 366 (Inches) To use our online Volumetric Weight Calculator, simply enter the dimensions of the package that is being transported and that you'd like to know the volumetric weight of Volumetric Efficiency Calculation??` Reply Prev of 3. 2 3 Next Reply Author. Discussion. stevesingo. Original Poster. 4,356 posts. 187 months. Sunday 8th September 2013. Can I calculate my VE from.

- What is
**volumetric****efficiency**? If you crank a 1-liter engine over two revolutions, under ideal conditions, it would pump 1 liter of air. This represents 100%**volumetric****efficiency** - The volumetric efficiency significantly varied with the engine speed, and appeared to be slightly affected by the diesel replacement rate (Fig. 12). Fig. 12 . Volumetric efficiency measured by Mahgoub et al. [98] with the use of composition A ( Table 4 )
- Volumetric Efficiency = (actual airflow/theoretical airflow) x 100. Most engines can breathe close to 100 percent volumetric efficiency at low rpms with full throttle. A closed throttle or part throttle creates a restriction that reduces efficiency. Efficiency also drops off sharply as engine speed increases
- Specifically, the volumetric efficiency is the ratio (or percentage) of the volume of air which the cylinder/s collect during the suction stroke compared to the volume of the cylinder/s under the static condition. Most naturally aspirated (NA) engines attain the max. efficiency of about 80% at certain engine speed
- volumetric efficiency: the volumetric efficiency is a measure of the efficiency of the engine moving the intake charge into the chamber and the exhaust out. Typical values are as follows: 2 valve head - 80% 4 valve head - 88% it is not unusual however to have VE's of 95% or more in correctly built race engines : target horsepowe
- The Automotive Training Group, Inc. (ATG) provides live training classes and manuals and now offers on online Volumetric Efficiency (VE) app. The app is also available for iOS and Android. According to ATG's VE Calculator instructions, VE is a ratio of actual engine breathing volume to displacement
- This calculator is designed to give the engine's air intake volume requirements. Enter the designation of displacement, 1 for cubic inches or 2 for cubic centimeters. Enter the engine displacement size for the designation. Enter the anticipated maximum safe engine RPMs, typically known as red line. Enter the volumetric efficiency of the engine

More specifically, volumetric efficiency is a ratio (or percentage) of the mass of air and fuel that is trapped by the cylinder during induction divided by the mass that would occupy the displaced volume if the air density in the cylinder were equal to the ambient air density On the other hand, superchargers and turbochargers increase the pressure entering the cylinders, giving the engine a volumetric efficiency greater than 100%. However, if the cylinder is pulling in a vacuum, then the engine has less than 100% volumetric efficiency. Normally aspirated engines typically run anywhere between 80% and 100% VE To calculate the size of the filter required we have used data from The State of Louisiana, Department of Natural Resources. They have given a number of 2.5 cfm per square inch of filter for a HVAC application. To calculate and engine's volumetric efficiency, we have used this websit The JavaScript calculator below calculates the VAF (volume of outside air flow) in cubic feet per minute (CFM) and liters per minute (LPM) based on engine displacement (CI or L), speed (RPM), and volumetric efficiency (VE). For this exercise, I define the volumetric efficiency as the product of the natural flow capacity (NC) of the engine, at a. Volumetric efficiency • The volumetric efficiency is probably one of the most variable efficiencies governing the performance of engines. It is a measure of the effectiveness of an engine and exhaust system as air pumping devices. The volumetric efficiency is effected by a great many variables

Overall efficiency is simply the product of volumetric and mechanical/hydraulic efficiency. So continuing with the above example, the overall efficiency of the pump is 0.9 x 0.91 x 100 = 82%. Overall efficiency is used to calculate the drive power required by a pump at a given flow and pressure Volumetric efficiency is used to describe the amount of fuel/air in the cylinder in relation to regular atmospheric air. If the cylinder is filled with fuel/air at atmospheric pressure, then the engine is said to have 100% volumetric efficiency. On the other hand, super chargers and turbo chargers increase the pressure entering the cylinder, giving [

** Volumetric efficiency is a ratio of the pressure inside the engine and atmospheric pressure**. A volumetric efficiency value of one means they are the same, a value greater than one means the pressure inside the engine is greater than atmospheric (on a N/A engine, commonly caused by a 'ram air' effect and resonance), and a value less than one. And mechanical-hydraulic efficiency during retraction is: 1 - (500/5000) = 1 - 0.1 = 0.90 = 90% Overall efficiency is simply the product of volumetric and mechanical/hydraulic efficiency. In a modern hydraulic cylinder, where volumetric efficiency approaches 100%, overall efficiency equals mechanical/hydraulic efficiency: 0.95 x 1 = 0.95 = 95%

Calculating volumetric efficiencyThe volumetric efficiency is simply the actual volumetric flow rate divided by the theoretical volumetric flow rate multiplied by one hundred.Equation 4 shows the volumetric efficiency using the data from the previous two equations Volumetric efficiency of compressor is the measure of the deviation from volume handling capacity of compressor. Mathematically, the volumetric efficiency is given by the ratio of actual volume of air sucked and swept volume of cylinder. Ideally the volume of air sucked should be equal to the swept volume of cylinder, but it is not so in actual. IE5 energy class is the highest efficiency motor as well as EFF3 class motors are the lowest energy class motor. Example: Calculate the efficiency of the motor input power is 55kW and the output power is 45kW. Apply our formula, Motor efficiency (%) = 45 * 100 / 55 = 81.8%. The motor has 81.8% efficiency B gi = formation volume factor for gas at initial conditions (RES ft 3 / SCF standard cubic feet) Recoverable reserves are a fraction of the OOIP original oil in place or OGIP original gas in place and are dependent on the efficiency of the reservoir drive mechanism. The basic equation used to calculate recoverable oil reserves i Volumetric Efficiency Calculator. Justin Owner/Technician Wisconsin Posted Latest Edited . Question. Unsolved . Tooling. Whats a good one and links. Reply Bookmark Share. 0. So I use the ve calculator a lot and the pressure waveform overlay every time I do in cylinder compression. Was going to buy a pico just for those features and now I.

Volumetric Efficiency. Drive the vehicle while recording the related pids with a scan tool and afterwards input the collected data into a VE calculator - done! An expert is someone who knows each time more on each time less, until he finally knows absolutely everything about absolutely nothing System designers use the pump manufacturers' volumetric efficiency value to calculate the actual flow a pump of a given displacement, operating at a particular pressure, will deliver. As already mentioned, volumetric efficiency is used in the field to assess the condition of a pump, based on the increase in internal leakage due to wear or damage More specifically, volumetric efficiency is a ratio (or percentage) of the quantity of air that is trapped by the cylinder during induction over the swept volume of the cylinder under static conditions. In the case of forced induction volumetric efficiency can exceed 100% I know it is a joke, but you can actually achieve higher than 100% volumetric efficiency. It high RPM with very very well designed intake and engine you will have enough momentum in the intake charge to actually pack air into the cylinders at slightly higher than atmospheric pressure Simply put, the volumetric efficiency is the ratio of air going into the engine to the ratio of air that the cylinder geometry can accommodate at standard pressure. A volumetric efficiency of 90%, therefore, means that only enough air to fill 5.58L is actually going into the engine but that 5.58L is being spread out over the full 6.2L.

In this month's Enginology section CIRCLE TRACK contributor takes a look at volumetric efficiency and how configuring intake, exhaust and camshaft packages can to manipulate torque curves to. Rotary positive displacement (RPD) pumps theoretically displace a fixed amount of fluid per revolution. However, some loss in output is typically caused by the fluid slipping past the rotors. The difference between the quantity displaced (Qd) and the actual output quantity (Q) is slip (Sq). The volumetric efficiency of RPD pumps depends on the percentage of slip to the total quantity displaced Volumetric Efficiency and Engine Airflow In a four-stroke naturally aspirated engine, the theoretical maximum volume of air that each cylinder can ingest during the intake cycle is equal to the swept volume of that cylinder (0.7854 x bore x bore x stroke). Since each cylinder has one intake stroke every two revolutions of the crankshaft Volumetric Efficiency Calculator Use this tool to determine if a MAF is probably functioning correctly. Note: This is set up for Naturally Aspirated engines

- The volumetric efficiency can be expressed as: η v = q / (q + q l) (3) where. η v = volumetric efficiency. q = volume flow out of the pump or fan (m 3 /s) q l = leakage volume flow (m 3 /s) Total Loss and Overall Efficiency. The overall efficiency is the ratio of power actually gained by the fluid to power supplied to the shaft
- actual air flow = ideal air flow x volumetric efficiency. Example. Time for an example. Lets calculate the pounds of air flowing into an engine for two different cars, an intercooled '87 and a nonintercooled '85. For both cars we will use a volumetric efficiency of 0.85. For both cars the engine is turning at 5000 rpm
- Calculating Volumetric Efficiency (VE) By DarinS in forum Forced Induction Replies: 3 Last Post: 01-22-2015, 02:23 PM. A Few Thoughts on Volumetric Efficiency and Power. By MirrorrorriM in forum General BMW Mechanical Help sponsored by RM European Auto Parts. Replies:
- the volumetric efficiency figure can be brought to. engine performance. Volumetric efficiency may. over 100 percent. Principles of supercharging. calculate the compression ratio, do the. following: (1) Divide the volume at bottom dead center. by the volume at top dead center. 80cu in. 10cu in. =
- The volumetric efficiency significantly affects the engine output parameters: power, torque, fuel consumption and exhaust emissions. Both design and dimensions of an intake and exhaust system have.
- What's Your Estimated Volumetric Efficiency? Jump to Latest Follow 1 - 15 of 15 Posts. J. Jack Armstrong The calculator shows 93.6% based on HP and 102.9% based on TQ. Jason Gore AKA DragRacer Naturally Aspriated 450 SBC - 915 HP / 714 lb-ft 3370 lbs 1.36 - 60', 5.93 @ 116.7 MPH - 1/8th
- The problem I am having is trying to get realistic numbers from this formula for a boosted engine. Since forced induction can increase the volumetric efficiency of an engine the amount of air an engine can flow (CFM) should not only increase based on RPM, but also Volumetric Efficiency (VE). Displacement and Pressure Ratio stay the same

- Volumetric Efficiency % Cubic Feet/Minute CFM This calculator is supplied as a convenience and intended to be used for estimates only. We make no warranties, implied or expressed, to the accuracy of any data or calculations presented here
- The compressor has a high volumetric efficiency (see Fig. 12.11) and best performance factor. It is quieter and less vibration. It is quieter and less vibration. Spiral compressors available in a range from 3 to 50 kW, with air-cooled condensers
- So then the volumetric efficiency can be said as the 80% (80/100)*100 = 80%. The normal range of volumetric efficiency of an SI engine is between 80 to 85% at full throttle, whereas the CI engine would stand at 85 to 90%. And the Gas Engines have much lower volumetric efficiency
- Volumetric Efficiency: Volumetric efficiency includes many factors that help explain the differences between ideal gas behavior and real gas behavior. In general, volumetric efficiency depends upon compression ratio, cylinder clearances, gas compressibility values and the ratio of specific heats (k or N value)
- Generally turbocharger used to increase volumetric (breathing) efficiency of an engine. First we need to know about Volumetric efficiency..(wikipedia definition) Volumetric efficiency in internal combustion engine engineering is defined as the rat..
- RE: Turbo/supercharged Volumetric Efficiency Marquis (Automotive) 4 Mar 03 16:59 Rod, we run our supercharged Jags with quite short cam durations timed with no overlap at all,with perhaps a little via the ramps-else we find fresh charge is just pushed through to the exhaust

Define volumetric efficiency. volumetric efficiency synonyms, volumetric efficiency pronunciation, volumetric efficiency translation, English dictionary definition of volumetric efficiency. n 1. the ratio of fluid delivered by a piston or ram pump per stroke to the displacement volume of the piston or ram 2. the ratio of air or gas-air mixtur ** Volumetric efficiency (in simple terms) is how much air gets filled in the engine**. To explain this, consider an engine with a displacement of say 600cc. Now during the intake stroke, air is filled in because the intake valve is opened. Theoretical..

CALCULATION OF A THERMODYNAMIC REFERENCE PROCESS In the following, an idealized thermodynamic reference process is introduced to allow the definition of efficiencies 4.1 Volumetric and Isentropic Efficiency of a Compressor with Inner Admission && &. a: & & ()( )() ()( )( Volumetric Efficiency Calc free download - Moffsoft FreeCalc, Calc98, Efficient Calendar Free, and many more program digester volume (ft3) x 100% 8. Gas production (cu ft / lb VS) = gas produced (ft3 / day) VS destroyed (lbs / day) HORSEPOWER, FORCE, CHEMICAL PUMPS 1. Water HP = Q(gpm) x 8.34 lbs / gal x head (ft) 33,000 ft-lbs / min 2. Break HP = Water HP pump efficiency 3. Motor HP = BHP motor efficiency 4

Volumetric efficiency in a piston combustion engine depends on many factors, which can be classified as those related to the design and service. Design parameters that subst antially affect th Notes: Most Street engines are capable of achieving only about 80% VE (Volumetric Efficiency). A modified street engine with ported heads, headers, intake and carburetor can achieve about 85% VE. With extensive head and valve work and a new cam an engine may reach 95% or even more Calculating VE -**Volumetric** **Efficiency** VE = (AVF ÷ TAF) x 100 The calculation does not apply a correction factor for Altitude, Temperature and Humidity. The calculation assumes the necessary modifications for ambient condition through the use of IAT and MAF. VE specification = 75% to 90%. Diesel and Turbo charged engines could result with. well volumetric efficiency of an engine is the ratio of the actual volume of air at atmospheric pressure and abmiant temp. that gets into the engine on the intake stroke over the total volume at BDC. as the rpm increases it has less time to suck in air so the volumetric efficiency decreases as rpm increases

Brake specific fuel consumption (BSFC) is a parameter that reflects the efficiency of a combustion engine which burns fuel and produces rotational power (at the shaft or crankshaft). In automotive applications, BSFC is used to evaluate the efficiency of the internal combustion engines (ICE).The keyword brake is related to the use of a dynamometer (electrical brake) to measure the engine. Volumetric efficiency should be computed at the expected operating RPM or your engine application. Use the following examples as a guide to estimate the volumetric effi-ciency of your engine. (A) An ordinary low-performance engine has a volumetric efficiency of about 80% at maximum torque. (B) A high-performance engine has a volumetric.

The difference is that they are found using the theoretical volumetric flow rate (Q th) instead of the measured volumetric flow rate (Q m), i.e. we assume that the volumetric efficiency is 100%. Equation (4) from the power page shows the relationship between the BMEP and the measured engine torque The step-by-step calculation for shortcut method. a. Calculate the isentropic exponent (k) by Equation 3 using the average temperature defined by T = (T 1 +3T 2)/4. This form of average temperature was defined to obtain better match between the rigorous and shortcut method results. b. Calculate the isentropic efficiency (η Isen) by Equation 5 Volumetric Efficiency is a percentage of what fuel/air enters the combustion cylinder against that cylinders theoretical capacity. This PID will give the best results if your vehicle supports both MAF and MAP sensors. If both are supported, will show a range typically from 40 to 100%