To allow the air to enter into the cylinder or the exhaust, gases to escape from the cylinder, valves are provided, known as inlet and exhaust valves respectively. Why remapping a naturallyaspirated car is totally worth. Software for optimal setting and design of engines and. The most common mistake is to choose the wrong combination of engine components, making the engine run worse than stock. Tech tune racing motorcross race winning performance 2. Two stroke high performance engine design and tuning by. Four stroke cycle intake stroke piston moving down intake valve open exhaust valve closed 20091005 mmpmm 2 3. One of the main actions of preparation and development of a 4stroke engine consists in the modification of the camshaft. One was george sychrovskys excellent piece two stroke engine mystery solved, dealing largely with how to correctly operate one of the beasts.
A fourstroke engine has four main strokes to its cycle the first stroke, called the intake stroke, the crankshaft pulls down the piston by rotating. In ford sales literature, it was referred to as the eao or ohc engine and because it was designed to the metric system, it was sometimes called the metric engine. The intake valve is open at this point in the cycle, and air will be pulled through the intake manifold into the motor. There is quite a large section on changing the face of production racing and into the marlboro series and the lc era and through the kr1s and rgv eras. Other books to his credit are modern engine tuning, twostroke performance tuning. On a stroker things like matching the ports to the liner, crankcase to transfers etc. Pdf improving the performance of twostroke motorcycle with. Compression stroke piston moving up intake valve closed exhaust valve closed four stroke cycle 20091005 mmpmm 3 4. A stroke refers to the full travel of the piston along the cylinder, in either direction.
Every aspect of tuning a petrol engine gets covered. In an attempt to acquire that understanding i began a study of the highspeed, highoutput twostroke engine that has led to the. It explains in nontechnical language how modern engines can be modified for road and club competition use, with the emphasis. A myriad of different aftermarket accessories is available for you to custom tune your bike to better suit your needs. The internal ford codename for the unit was the t88series engine. A fourstroke cycle engine is an internal combustion engine that utilizes four distinct piston strokes intake, compression, power, and exhaust to complete one operating cycle. The morbidelli 125 twin road racer is a rotary valve engine. Geared specifically for gp and kart racers, this hardcover treasure has turned out to be a great reference source for questions on the logic and concepts that pertain to tuning a 2stroke for maximum performance. First published in 1989 as tuning new generation engines, this bestselling book has been fully updated to include the latest developments in fourstroke engine technology in the era of pollution controls, unleaded and lowlead petrol, and electronic management systems. A fourstroke also fourcycle engine is an internal combustion ic engine in which the piston completes four separate strokes while turning the crankshaft. Two stroke performance tuning chapter 3 porting and cylinder scavenging today, when we take a look down the cylinder of a twostroke engine, we find its walls literally filled with ports to handle the induction, transfer and exhaust phases of gas flow through the engine. The descending piston draws a mixture of fuel and air through the open intake valve. Other books to his credit are modern engine tuning, twostroke.
New material on electronic fuel injection and computerized engine management systems. There are some very good two stroke tuning guides from lodgemark press they have done most of the guides that kart racers use. Engine tuning the rc gas engine for radio controlled planes will ensure proper acceleration and keep top speed without harm the engine. Undoubtedly, the virtue which has most contributed to the widespread use and varied application of the twostroke engine is its mechanical simplicity. Mxa mixes vp110 with pump gas for use in slightly modified twostroke engines in. I just finished reading the complete book and was amazed at the level of detail and. Software for fine tuning and design of four stroke engine. Detailed modifications and improvements are described. Principles and working of fourstroke gasoline engine. First rule of 2 stroke or any tuning is to make it like it should be, i.
Those of us who have grown up in the japanese twostroke. From the bellmouth of the carburetor, to the insert of the reed valve and the reed petals, at the studied of the cylinder ports, until to the balance of the crankshaft, thanks at our software you could optimize your engine and to develop new. Great book to read if you are planning an engine tune. Basic concept of tuning a 4 stroke petrol engine the. This free downloadable guide comes right out of the two stroke dirt bike engine building handbook. A reference book for the enthusiast engine tuner and race engine builder. Graham bell is an acknowledged expert on engine tuning, with many years experience in this field. This book covers the process of building 4stroke engines to a professional standard, from selecting materials and planning work, right through to methods of final assembly and. With the experience or the simulation you can determine the new timings and the new maximum lift, but what remains problematic is the determination of the lift law and of the cam profile, this to maximize the volumetric efficiency and in the meantime check out the valve. It covers my early days in the motorcycle trade, on to starting my own mc business then forming my tuning business.
Vp110 is a good, allaround fuel for hoppedup twostroke engines. This stroke of the piston begins at top dead center t. Read this document before reading the applicable tuning section for those controllers, which are here. Bells fourstroke performance tuning book, this book goes into extreme detail regarding performance tuning a twostroke engine. A fourstroke engine also known as fourcycle is an internal combustion engine in which the piston completes four separate strokes which comprise. On the other hand, while the twostroke engine does not commonly require large dollar inputs to raise its power output, it does require an indepth under standing on the part of the man doing the modifications. Drawing on the authors many years of practical experience in tuning and modifying highperformance road, rally and race units, every aspect of an engines operation is explained and analysed.
I usually recommend this book along with gordon jennings two stroke tuners handbook, because this book has what the first one doesnt and vice versa. A 4stroke engine compresses the fuel air mixture before the gas explosion in the first two strokes and then there are two strokes that push the burnt gases out the exhaust. The piston make two complete passes in the cylinder to complete one o. This book really does cover all aspects of tuningmodifying a 4cylinder naturally aspirated engine and is therefore applicable to the majority of na cars in the uk. Four stroke engine tuning and fuel question rc groups. First published more than 30 years ago and in continuous print ever since, this remains one of the most comprehensive references available to the enthusiast engine tuner and race engine builder. Here are some useful tips for tuning your gas engine. Specialising in 2stroke performance services such as porting, cylinder repair and sleeving, crankshaft and engine rebuilding. Performance engineering 2stroke tuning we specialise in honda 2strokes, covering the cr range of motorcross bikes, the nsr250 street bikes, and hrc grand prix 125, 250, and 500s. It is important to us that you are happy with all the work that is carried out so you come back to us and share positive feedback with others about the service you received. Ive spent a lot of time looking for a performance related book that reflected both real world ideas and understanding with a hint of engineering in the explanations and the fourstroke performance tuning has met and exceeded what i thought was available.
Present a new 4 stroke engine concept invented by andrew feliks. For manufacter and tuner of two stroke engine, ntproject has developed a series of software to help in the development of the engine and its components. The valves are operated by the action of the camshaft, which has separate cams for the inlet. The guide covers everything you need to know about the correct use and implementation of precision measurement tools when rebuilding your two stroke. The piston crown opens and closes the exhaust and transfer ports. After this is complete the camshaft rotates to the low spot on the lobe. Two stroke performance tuning a disc partially cut away and attached to the end of the crankshaft opens and closes an inlet port in the side of the crankcase. Nick swager secrets of speed todays techniques for 4stroke. Everyday low prices and free delivery on eligible orders.
I am very proud of the riders i helped and sponsored and there is an appendix. In this cycle there are 4 different strokes, they are 1. Balancing the crank dynamically, getting correct piston to bore clearance, using good rings with correct end gap, matching piston weights. Graham bell second edition this is the moped performance tuning bible as far as im concerned. Recently i opined with a recommendation of two extremely well written articles on dealing with two strokes. The most common engine cycle involves four strokes. What really came in handy for me was the exhaust design calculations and how to choose right size diameter and length itbs for my engine.
Engine in which piston completes the cycle in 4 complete rotation of the crankshaft. The 2stroke engine compresses with a stroke upward and exhausts with a stroke downward. Drawing on the authors many years of experience in tuning and modifying highperformance road, rally and race units, every aspect of an engines operation is explained and analyzed. Other books to his credit are modern engine tuning, twostroke performance tuning and forced induction performance tuning. The is an introduction to tuning with a programmable electronic fuel injection ecu. Tuning the worlds first twinturbo c8 corvette makes 643whp, and thats just the start tuning the mercedesamg a45 s has been tuned to almost 500ps tuning watch a toyota gr supra engine dyno at. The process of building 4stroke engines to a professional standard, from selecting. Once knowing the working principles, this work will become much easier. Improving the performance of twostroke motorcycle with.