How to increase the power of a piston engine or how to modify the cylinder head

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The design of any internal combustion engine, including VAZ 2109 engines with 8 valves, requires the following components:

• The combustion chamber;
• Valve mechanism;
• Cast lines;
• Exhaust manifolds;
• Intake manifolds.

If you bore and correct the current state of the manifold and cylinder head channels, you can increase the cylinder filling ratio, which leads to increased efficiency and engine power. It is not uncommon for modifications to be performed as the final stage in increasing the volume of the internal combustion engine.

Object of improvement

Docking of cylinder head channels and manifolds

The main thing to look out for is an inappropriate/imprecise connection between the manifold valves and the cylinder head. The appearance of the slightest irregularities or steps can lead to undesirable consequences, which begin to slow down movement, partially blocking the channel and therefore they must be removed. After removing areas with obvious inconsistencies, the manifold gaskets need to be modified, as they can also be a barrier to flow.

It is also necessary to seat the collector on the pins. This is extremely important to do because the fasteners holding the manifolds can stretch and, as a result, there is a slight change in the planes of the cylinder head relative to the manifold. If this is not done, then all work to prevent inconsistencies will be useless.

I would like to note that it is necessary to place two pins on the collector (at the edges).

Before connecting the cylinder head and the manifold, you need to make a hole using cutters to refine the cylinder head. Then we put the pin on the head and place the collector on it. It is important that the second one sits freely, but there should be no backlash. You can then guarantee the exact positioning of these two elements with great confidence. You also need to make a few holes in the gasket. This is how optimal docking should be done.

Pros and cons of R/S below normal

Plus:

chambers are maximally filled at low and medium speeds, improved combustion and ignition.

Minus:

a large roll angle of the connecting rod can mean its premature failure, rupture into two parts, accelerated wear of the rings, cylinder walls, and insufficient lubrication.

Before you upgrade

, the car owner needs to clearly understand where he will use his car and in what modes. If you just trot through the night streets and disturb residents, then there is no point, if you participate in races, then maybe there is some point.

According to experts and experienced drivers, there is no particular need to tune the domestic auto industry, and the effect of this is small; it would be more rational to start saving for a cheap foreign car, for example, for the same budget Opel. As a result, you will get maximum results and productivity.

As you can see, boring the cylinder block on a VAZ 2109 is possible and effective, but this coefficient may not always satisfy everyone.

Source

Channels

Refinement of the cylinder head also involves the need to modify the channels, since they may have a deformed shape, metal under the bushings, etc. The channels are refined using a ball cutter. It’s better when you have not one cutter, but several with different parameters (sizes and shapes). By working with a milling cutter, you can remove any irregularities and also increase the cross-section.

It is extremely important to ensure that the channel bend is as smooth as possible and that the appropriate curvature dimensions are observed. The surface on the intake channels should be slightly rough - this promotes good evaporation of gasoline from its walls. The exhaust channel can be polished to a shine. The cross-section of the channel should not be circular, but slightly elliptical. When enlarging the channels, it is important not to overdo it; you need to know when to stop, since there is a possibility of hitting the cooling channel or oil channel. The cylinder head on classic engines allows you to enlarge and expand the channels, while on 8-valve VAZ engines problems are inevitable.

Before you start directly boring the channels, you should find out where to start this process - from the manifold or GB. If you need to significantly increase the diameter of the valves, then it is better to start from the area where their walls are thinner. This way you will reduce the risk of accidentally opening the channels the next time you combine them. The parts of the bushings that protrude into the channels also need to be modified so that they do not create interference.

As a rule, they need to be either shortened or sharpened. There are situations when the bushings grind off the valve wall. Some car enthusiasts consider this method the best in terms of benefits, although in practice rarely anyone does this, since it significantly reduces the service life of the guides. Correct modification of valves is possible only under two conditions: experience and following the instructions.

Stages of engine overhaul repair

On the eve of a major overhaul, it is necessary to draw up a detailed action plan:

It turns out which VAZ 2109 engine repairs you can do yourself, and which ones you must trust to a car repair mechanic. Necessary:

• choose a place for major repairs - in the best case, it is carried out in the pit of your own garage;
• choose a decent lifting mechanism with slings for securing loads - it helps to remove the power plant unit;
• the engine parts that have been removed must be placed in special trays that are suitable in size for the engine;
• You should not purchase spare parts for the engine in advance - having removed them, you can come to the conclusion that they have become unusable and only then go to the auto store for spare parts;
• if the engine is in very poor condition, a second-generation power plant is immediately purchased complete with a cylinder block for a complete replacement;
• it is necessary to calculate your financial potential and clearly calculate how much time it will take for major repairs, since this is a very long-term undertaking.

Valves

Refinement of valves consists of reducing weight and increasing throughput. To make the valve lighter, it needs to be reground or reground. In this case, excess metal will be removed from both sides. The valve stem is also subject to modification - it needs to be narrowed. You can also choose the option without replacing the bushings; in this case, you need to make the leg thinner along the entire area from the guide bushing to the plate. Particular results can be achieved by reducing the diameter of the stem. For example, reducing the stem from eight mm to seven helps reduce the mass of the rod itself by 20% and increases throughput (this is in 8-valve engines).

In reality, the valves are made from an alloy of titanium and aluminum and therefore have amazing lightness, which is combined with some unpleasant aspects: high cost and fragility. Given this fragility, strict recommendations are made for springs and valve seats. The springs may remain factory or may be slightly weakened. It is advisable to change the saddles to others made of bronze.

How to determine a motor malfunction

The engine of a VAZ 2109 car, together with the gearbox and clutch, constitute a power unit, which makes up a single unit located on three rubber-metal elastic supports fixed in the engine compartment. Some faults can be diagnosed independently:

• Increased clearances in the assembly, very early ignition or insufficient oil pressure are indicated by a metallic, dull sound of the crankshaft main bearings.
• A large gap in the bearings or insufficient oil pressure can be indicated by a sharp knock in the connecting rod bearings.
• Replacement of pistons or piston rings will be necessary when the piston knocks, which is caused by its beating in the cylinder.
• A broken valve spring or mismatched clearances can be characterized by a uniform, constant knocking sound in the valves. To identify worn elements, you need to perform a visual inspection of the unit.
• The ingress of foreign particles under the oil pressure valve and failure of the oil pump can be determined by insufficient oil pressure at idle when the engine is warm. When using low-quality motor oil, such problems may also arise.
• Excessive pressure in the oil lubrication system indicates that the pressure relief valve is stuck or its spring is too stiff. After replacing the appropriate elements, this problem is eliminated.
• An increase in oil consumption can be caused by increased wear of piston rings, engine seals, valve stems, guide bushings, and oil seals.

Combustion chamber shape

Refinement of the cylinder head also involves changing the shape of the combustion chamber. In this case, three areas of work can be distinguished:

1. Reduced detonation
2. Improvement for cylinder filling
3. Fulfillment of conditions for optimal distribution of the mixture in the combustion chamber.

Detonation places severe stress on the pistons and rings. It can be determined by the level of metallic sounds that spread throughout the car engine. The sources of this phenomenon can be the most remote areas of the combustion chamber from the spark plug. This can be solved this way: · It is necessary to reduce to a minimum the work in the combustion chamber, which increases the spread of combustion. · It is necessary to minimize the number of CS sections. These areas include camera corners and sharp edges. To do this, you need to smooth the surface as thoroughly as possible.

The last two steps to improve the shape of the combustion chamber are very difficult to do on your own, since you need to have excellent knowledge of physics.

Refinement of the cylinder head is quite simple at some stages and is a completely justifiable procedure. Proper modification will increase the power of your car's engine.

Pros and cons of R/S above normal

Pros:

• combustion of the maximum amount of mixture due to being at top dead center for a long time;
• elevated temperature and high blood pressure;
• excellent performance at low and medium speeds.

Minuses:

• insufficient filling of the combustion chamber at medium speeds;
• frequent occurrence of detonation due to elevated temperature.

Maintenance

The classic internal combustion engine design in combination with a transverse engine arrangement under the hood of front-wheel drive cars is subject to the following maintenance regulations:

The accompanying instructions contain a description of the parameters; the manufacturer strongly recommends following the maintenance procedure for engines 21083.

VAZ engine repair in Ulan-Ude - prices

Sayan: We need to overhaul the VAZ 2103 internal combustion engine and the approximate cost of the work

• Car service "Pegasus Auto": Hello. Work from 25t.r.

• Oleg: price, and how many days for repairs, capitalization
• Car service "Pegasus Auto": Hello! Work 22 thousand. Time 2-3 days.

Car service "Autocomplex on Trubacheeva - Service Station Motom": Engine repair without boring and spare parts 17-18,000 rubles, while busy

• Auto service "Turbo": Hello. The cost of work will be 19,000 rubles without the cost of parts. By time from 3 to 7 days

Why bore the cylinder block?

Block boring is a special process through which the geometry of the machine’s engine cylinders can be restored.

It is necessary to bore the cylinder block for a number of reasons:

1. Thanks to this procedure, the natural position of the mating components of the power unit relative to each other is restored.
2. To restore optimal wearability and correct positioning of components relative to the surface, cylinder geometry alone is not enough. The latter will also break during operation of the power unit.
3. As a result of the increased friction and stress that occurs with a lack of tolerance, other dependent units will continue to collapse. This will lead to the formation of additional loads on all moving parts of the internal combustion engine involved in the operation of the unit. As a result, cracks and bends will form on the devices, and the unit will be deformed.
4. Also, the boring or honing procedure is often performed to increase the motor power parameter. Although the cylinder walls of internal combustion engines are made of high-strength steel, this material tends to wear out when the pistons operate. The shape of the cylinders ends up being more oval than round, causing the piston rings to fit together.
5. As a result, due to detonation of the combustible mixture, exhaust gases enter the engine crankcase along with the mixture. This leads to a decrease in the overall power parameter of the internal combustion engine and the power unit begins to consume motor fluid.

Boring interval

The fact that the boring procedure is performed less frequently these days than it was 30 years ago is due to high technology. At that time, it was difficult to find quality oil or antifreeze for the engine. Therefore, the procedure for overhauling the unit and boring could be carried out after 50-60 thousand kilometers.

Today, thanks to the use of additives and additives in liquids by various manufacturers, wear of the unit can occur after 200 thousand kilometers. The honing procedure itself for the purpose of tuning or repair is performed on special machines where the devices are ground down. Then new, larger pistons are mounted on the power unit, which makes it possible to increase the service life of the internal combustion engine.

Artem Krupin spoke in detail about the goals pursued by cutting the channels of the motor BC head.

Tuning methods

Several types of tuning are used:

• “chipping” – installation of an electronic analogue of a mechanical regulator, power increases by a maximum of 15%;
• replacing the air filter - options with reduced resistance are used, an exhaust manifold with the same length of pipes and a 52 mm throttle.

The manufacturer does not recommend turbocharging the 21083 engine, as this significantly affects the service life for the worse.

Thus, modification 21083 was not the best internal combustion engine option for VAZ cars. However, a noticeable advantage is the safety of the valves in the event of a timing belt break, an improved Ozone carburetor and an increase in power by 6 hp. With.