ABSTRACT

In this manuscript, research on engine compression ratio is discussed. Objective this case

study is to prepare a report based on engine horsepower and capacity. The horsepower and

capacity engine is on developed internal combustion engine technology. Manufacturers will

compete to improve the engine with new technology. Increase their efficiency, compact cars

selected based on higher unit sales in Malaysia. Between 1.6cc engine analyzed in learning

technology brand manufacturers Ford, Volkswagen and Morris Mini.

Ford fiesta Vi-VTIC selected based technologies designed to power acceleration and fuel

economy. System provides efficient burning when need high RPM. Volkswagen selected

technology based on new 7-speed DSG transmission capacity that provides ride comfort when

you want to change the speed. DSG resulting from research engineers determine the cause of the

power is the transmission power reduction whiles the engine to the transmission. Mini cooper S

with selected based on the amount of compression ratio 8.3:1 but large capacity 1598cc because

engineers have made this problem is solved by installing supercharge to improve the

performance of the engine during acceleration. Mini cooper is a two passenger car using BMW

engineering develop.

Horsepower and fuel savings identified resources in the development of an engine. Methods of

achieving the objectives, turbo and supercharger installations needed to provide acceleration

power sought. Clutch design changed so that problems can be overcome power disconnected.

Increased number of valves in each cylinder with twin cam design helps to get a high amount of

compression and the power of the rich. Horsepower to consider the cost of fuel consumption but

can be overcome by installing a magnet on the fuel pipe to make magnets work for savings

available.

Results found effective thermal efficiency is Foard Fiesta TI-VCTI is thermal effective of 62%

and following this result is the Volkswagen engine 1.6 Polo of 61% an engine design that has the

good thermal efficiency. Mimi cooper S engine gets low thermal efficiency of 57% due to the

use of a supercharger. If the compression ratios increase cause the engine to overheat.

1

INTRODUCTION

The internal combustion engine is a heat engine in which the burning of a fuel occurs in a

confined space called a combustion chamber. This exothermic reaction of a fuel with an oxidizer

creates gases of high temperature and pressure, which are permitted to expand. The defining

feature of an internal combustion engine is that useful work is performed by the expanding hot

gases acting directly to cause movement. Engine efficiency refers to an engine's ability to

transform the available energy from its fuel into useful work power.

Gasoline (petrol) Engines

Particularly reciprocating four stroke engines produce moderately high pollution levels, due to

incomplete combustion of carbonaceous fuel, leading to carbon monoxide and some as along

with oxides of nitrogen & sulfur and some unburnt hydrocarbons depending on the operating

conditions and the fuel/air.

Compression ratio

Efficiency of internal combustion engines depends on several factors, one of which is the

compression ratio. A greater compression ratio the more efficient on the engine. Conventional

high compression ratio engines require gasoline with higher.

Thermal efficiency

The efficiency of internal combustion engines depends on several factors, one of which is the

compression ratio. Most gasoline engines have a geometric compression ratio (the compression

ratio calculated purely from the geometry of the mechanical parts) of 10:1 (premium fuel) or 9:1

(regular fuel), with some high-performance engines reaching a ratio of 12:1 with special fuels.

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STUDY OBJECTIVE

The main purpose of this learning case made is to perform calculations for the thermal

efficiency of the best among the three types of engines.

Thermal efficiency figures will be revised in percent and a difference between the three

types of machines.

The calculation of heat can also determine the level of performance of an engine via data

collected through the compression ratio specifications of attached to the data of a vehicle

designed by the manufacturer.

Formula calculation for the thermal efficiency :

ɱ = 1-

Allow the calculation results for the thermal efficiency engines for maximum horsepower

and efficient control of the combustion engine to achieve the reduction of gas flaring.

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SCOPE OF STUDY

Three Brand Engine

( Manufacturing )

FORD FIESTA- Ti-VCT I (1.6cc)

VOLKSWAGEN POLO TRENDLINE – DOHC

(1.6cc)

MINI COOPER S ENGINE-SOHC

(1.6cc)

Compact car

OHV 4-Stroke

Four Cylinder Engine

Petrol Engine

Selection of the engine based on thermal efficiency:

Type Engine Ti-VCT I-DOHC VW DOHC-DSGSOHC -

SUPERCHARGE

Compression ratio 11.0:1 10.5:1 8.3:1

Analysis of the engine

Type Engine 1.6-Ti-VCT I-DOHC VW DOHC+DSG1.6-SOHC /

SUPERCHARGE

Material engine Aluminum Alloy Aluminum Alloy Aluminum Alloy

Bore x stroke (mm) 79.0 x 81.4 87.0x76.5 77.0 x 85.8

Type Valve 16 Valve 16 Valve 8 Valve

Engine cc 1596 1598 1598

Horsepower 6350 rpm 5250 rpm 6000 rpm

Torque 5000 rpm 3500 rpm 3500 rpm

4

METHODOLOGY

FORD FIESTA

Specifications

ENGINE

Type 1.6-liter TI-VCT I-4

Cylinders 4

Configuration Aluminum block and head

Valve train DOHC, four valves per cylinder

Bore x stroke 3.10 x 3.20 in./79.0 x 81.4 mm

Displacement 97.4 cu. in./1,596 cc

Compression ratio 11.0:1

Horsepower 120 @ 6,350 rpm

Torque 112 lb.-ft. @ 5,000 rpm

Fuel capacity 12.4 gallons

Fuel injection sequential multiport electronic

Oil capacity 4.5 quarts with filter (gf4)

Emission control Three-way catalyst

DRIVETRAIN

Layout Front-wheel drive

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VOLKSWAGEN POLO 1.6 TRENDLINE

Specifications

Engine managementEngine Layout Transverse inline 4

Cylinders 4

Aspiration Natural

Valves DOHC 4 valves per cylinder

Bore / Stroke 87.0x76.5

Capacity 1598

Compression Ratio 10.5:1

Ignition Type Electronic

Fuel Capacity 45

Fuel Consumption - Highway 5.1

Fuel Consumption - Urban 8.7

Consumption Annual Average 6.4

Fuel Type Ron 95-98

Fuel Supply Multi-point electronic fuel injection

Acceleration 0-100 Final 11.3

Top Speed Final 188

Power Output 77kw@ 5250 rpm

Torque 155nm@ 3500 rpm

Limited Slip Diff No

Turning Circle (Meters) 10.6

6

DRIVETRAIN

Layout Front-wheel drive

MINI CABRIO R52 MY05 COOPER S - 2005

Specifications

Engine management

Manufacturer TRITEC

Aka MINI Cooper S Engine

Type Petrol - Premium

Displacement 1598 cc

Aspiration Supercharger

Configuration In-line 8 valve SOHC

Cylinders 4

Fuel System Electronic multi-point fuel injection

Lubrification Synthetic oil

Output 120 kW @ 6000 rpm

210 Nm of torque @ 4000 rpm

Bore 77.0mm (3.0 in)

Stroke 85.8mm (3.38 in)

Compression 8.3:1

In. Valves 30.23mm

Ex. Valves 23.26mm

Length 565mm

Height 675mm

Width 615mm

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Dry Weight 118 kg

Emission/s CO: g/km

CO2: g/km

NOx: g/km

Hydrocarbon: g/km

THE CRITERIA OF ENGINE

FORD FIESTA-1.6 cc Ti-VCT I

Fiesta’s advanced 1.6-liter engine features Twin Independent Variable Camshaft Timing

(Ti-VCT) allowing the engine to be downsized for fuel economy while continuously

optimizing camshaft phasing for throttle response, performance and flexibility.

Fiesta’s flowing sculpted hood covers a 1.6-DOHC engine with an estimated 119

horsepower and 109 ft.-lbs. of torque. Spirited performance and fuel-efficient economy

are signature attributes with the Fiesta expected to deliver best-in-class fuel economy at

40 mpg.

Big results from a small package are possible with several new technologies in this new

global engine, including an advanced new front end accessory drive (FEAD) belt with

stretchy dynamics to improve the engine’s thermal dynamics. The elasticity in this new

drive belt eliminates the need for a belt tensioner and contributes to overall fuel economy.

VOLKSWAGEN POLO TRENDLINE-1.6cc DOHC

Seven engines will be offered on the new Polo during its first year of production – four

gasoline and three diesels. All engines satisfy limits of the new Euro-5 emissions

standard.

The most powerful gasoline engine in the Polo lineup at the time of market launch is the

1.6 MPI that is equipped with new engine electronics and a new injection system as well.

The four-cylinder aluminum block engine outputs 85 PS (at 5,000 rpm). Its maximum

torque of 132 Newton-meter is available at 3,500 rpm

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Direct-Shift Gearbox

The world’s first 7-speed DSG for large-scale production. Engine power is transmitted to

the dual clutch via the crankshaft and a dual-mass flywheel. Clutch I handles the odd

numbered gears, and clutch dual the even gears plus reverse gear. When shifting, there

are no gaps in propulsive power.

MINI COOPER S ENGINE-1.6cc SOHC

The 2012 MINI Cooper is a compact car offered in standard, S, and John Cooper Works

trim levels. The standard FWD Cooper Coupe is powered by a 1.6-liter 4-cylinder engine

that produces 120 hp and 114 lb-ft of torque while the Cooper Hardtop S comes equipped

with a turbocharged 1.6-liter 4-cylinder engine that produces 181 hp and 177 lb-ft of

torque.

Made of aluminum alloy material. If the previous Cooper S has a supercharger, new

turbocharged. Effects of changes in engine design get high acceleration on the car.

A 6-speed manual comes standard on both trims but drivers also have the choice of an

optional 6-speed automatic.

THE SYSTEM OF ENGINE

Twin Independent Variable Camshaft TimingFunction

TI-VCT allows extremely precise, variable control of “valve overlap,” or the window of

time in which both the intake and exhaust valves in an engine are open at the same time.

By adjusting overlap continuously, an engine can operate at optimum settings for peak

fuel economy or power output as conditions demand.

TI-VCT also facilitates an “internal egr” effect, reducing nox (a contributor to smog)

and hydrocarbon emissions throughout the engine’s operating range.

Benefits of Ti-VCT Engines

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Up to a 7 percent improvement in peak power and a 5 percent improvement in low-speed

torque for better acceleration, passing and merging performance.

Up to a 4.5 percent improvement in fuel economy.

Reduced nox and hydrocarbon emissions without compromising idle quality.

Optimized cold-start operation minimizing cold-start emissions.

Cooper S engine has assembly Supercharger and Replace To Turbo

Supercharger

A supercharger is an air compressor used to increase the pressure, temperature, and

density of air supplied to an internal combustion engine. The compressed air that a

supercharger provides to an engine supplies a greater mass of oxygen per cycle of the

engine to support combustion than available to a naturally aspirated engine, which makes

it possible for more fuel to be burned and more work to be done per cycle, which

increases the power the engine produces.

Power for the supercharger can be provided mechanically by a belt, gear, shaft, or chain

connected to the engine's crankshaft. When power is provided by a turbine powered by

exhaust gas.

Turbocharger

A turbocharged engine can be more powerful and efficient than a naturally aspirated

engine because the turbine forces more intake air, proportionately more fuel, into the

combustion chamber than if atmospheric pressure alone is used.

VW DOHC engine combine with DSG transmission system

Function

The DSG technology is a groundbreaking “two-in-one” concept. Totally unlike a

conventional automatic transmission, it combines the fuel efficiency of a clutch-operated

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transmission with the convenience of automatic shifting. Twin electronically controlled

shafts manage gear selection, always anticipating your next shift.

Benefits of DSG:

Smooth gear changes at highway speed

Handling with unbroken acceleration

Faster shifting for better performance

Improved fuel economy

FINDING

Method of calculation

Type of Engine Ti-VCT I (1.6cc)POLO-DOHC

(1.6cc)

MINI COOPER S ENGINE-SOHC

(1.6cc)

Compression Ratio 11:1 10.5 :1 8.3:1

Formula Engine Thermal Efficiency

ɱ = 1-

0.616 or 62% 0.6095 or 61% 0.57 or 57%

Result calculation

No. Type of Engine Thermal Efficiency

1. Foard Fiesta TI-VCTI ɱ = 62%

2. Volkswagen 1.6 Polo - DOCH ɱ= 61%

3. Mini Cooper S SOHC / Supercharge ɱ = 57%

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DISCUSSION & SUGGESTION

1. Emission regulation is also applied vehicle engines.

Stringent exhaust emission regulation will be required in the future. Improvement in the thermal

efficiency capable of CO2 reduction is needed and is an important factor.

2. Increases horsepower at the engine through the modification process engineering.

i. Installation of the turbocharger on the engine as done in the mini cooper s engine to

increase the compression ratio for get maximum horsepower. Figure 1

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Figure 1 : VW boost horsepower engine with turbo and supercharger installations combination

(Twin charged)

ii. Clutch design needs to be changed to solve the problem of power transmission from the

engine to the transmission break connection. Clutch plate design should be on the

thickness of the clutch plate and spring strength. Figure 2

New design Standart design Cover clutch

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Figure 2: Clutch Plate design

3. Saving fuel even though the engine working at maximum horsepower.

i. Fuels Stratified Injection designed to separate the fuel molecules become evenly facilitate

the smooth mixture to improve combustion efficiency.

ii. Magnet assembly on the fuel pipe makes molecules subtle split mixture to make

completed engine combustion. Figure 3

Figure 3 : Magnet assembly on the fuel pipe.

4. Effective controls to reduce carbon in the combustion chamber.

Mini cooper S engine must be designed double overhead cam ‘DOHC’ with four valves in each cylinder to raise the compression ratio to obtain higher combustion power.

CONCLUSION

Engines selected are made of aluminum alloy materials by method casting.

The typical alloying elements are copper, magnesium, silicon and zinc. There are two principal

classifications, namely casting alloys and wrought alloys, both of which are further subdivided

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into the categories heat-treatable and non-heat-treatable. Aluminum alloys are widely used in

engineering structures and components where light weight or corrosion resistance is required.

Issues identified when comparing the third engine due to large capacity but small

compression ratio.

Mimi cooper engine gets low thermal efficiency of 57% due to the use of a supercharger. If the

compression ratios increase cause the engine to overheat. The compression ratio is reduced and

the engine operating time can be speeded up in order to produce maximum horsepower (6000

rpm). Engine bore small by size “diameter” x stroke (77.0 X 85.8) can produce high capacity

(rpm) assembly turbo or supercharge.

Engine with high efficiency using a 16 valve (Double Overhead Cam)

Foard Fiesta TI-VCTI is thermal effective of 62% and following this result is the Volkswagen

engine 1.6 Polo of 61% an engine design that has the best thermal efficiency. A difference in the

number of valves in each cylinder is the main source for engineers’ calculation of the

compression ratio in the combustion chamber. There are two types of design used the 2 valves in

each cylinder or 4 valves in each cylinder.

Thermal efficiency can help Nox gas emission reductions at the lowest level

The results on the thermal efficiency ratio of 62% proves that NOx emissions to a minimum

which has been verified by the association Automotive Euro. The ford combine system TI-VCT

engine with Ecoboost system in the operation engine.

APPENDIX

FORD FIESTA ( TI-VCT ) - 2008

Engine features Twin Independent Variable

Camshaft Timing (Ti-VCT) allowing the

engine to be downsized for fuel economy.

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VOLKSWAGEN POLO TRENDLINE- 1.6cc

The world’s first car using seven speed DSG

cause to be no gaps in propulsive power.

MINI CABRIO R52 MY05 COOPER S - 2005The next model mini cooper clubmen using

Turbocharger in the operation system engine

cause will be improve horsepower.

REFERENCE / BIBLIOGRAPHY

1. http://www.um.co.za/specifications/volkswagen_polo_1_6_comfortline_%282010%29.aspx

2. http://www.miniusa.com/#/MINIUSA.COM-m

3. http://www.ford.com/cars/fiesta/specifications/

4. http://assets.forddirect.fordvehicles.com/assets/2012_Ford_Fiesta_J1/NGBS/Nameplate_SpecificationLiteDoc/Nameplate_SpecificationLiteDoc_8801EF28-002C-14D9-028C-DC5A028CDC5A.pdf

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5. http://www.csgnetwork.com/compcalc.html

6. http://www.rbracing-rsr.com/compstaticcalc.html

7. http://en.wikipedia.org/wiki/Compression_ratio

8. http://www.wisegeek.com/what-is-thermal-efficiency.htm

9. http://en.wikipedia.org/wiki/Engine_efficiency

10. http://www.jsme.or.jp/English/jsme%20roadmap/No-7.pdf

11. http://wikicars.org/en/W11

12. http://www.netcarshow.com/ford/2008-fiesta/

13. http://www.topspeed.com/cars/volkswagen/2010-volkswagen-polo-ar71252.html

14. http://www.carsales.com.au/private/details/mini-cabrio-2005

15. http://www.vw.com/en/dsg/nav/what-is-dsg.html

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