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Shocks (AKA shock absorbers or dampers) are the most useful tool for adjusting corner entry and corner exit handling characteristics of a street car. They are easily accessible on most cars, and aftermarket shocks are usually adjustable in many ways. Shocks are necessary to dampen, or gradually reduce, the bouncing of the springs on the car. Without them, the suspension would oscillate up and down for an extended period of time after running over a bump or experiencing weight transfer.

There are two settings that determine the way a damper behaves: compression and rebound. Compression is the shock’s resistance to being pushed in, and rebound is the shocks resistance to being extended. When the car accelerates, weight is transferred to the rear, which results in the front wheels trying to lift off the ground and the rear wheels pushing harder into the ground. The front shocks are being extended while the rear shocks are getting compressed. Hence, during acceleration, the car is mainly affected by front rebound and rear compression. The opposite is true for deceleration. During deceleration, handling is affected by front compression and rear rebound.

So how do you use this information to adjust your car? First, you need to take note of what your car is doing on corner entry and exit. Shocks can be used to change the way a car handles going into a corner without noticeably affecting how it handles in the center or coming off the corner. This ability to change a specific characteristic about a car’s handling is what makes shocks so useful and important in suspension tuning. If your car is understeering on corner entry, you need to decrease front compression or increase rear rebound. If it is over steering on corner entry, increase front compression or decrease rear rebound.

You can find many other adjustments on the Suspension Setup Reference Chart at www.240edge.com/performance/reference.pdf.

Visit my website for more information about damper adjustments: www.240edge.com

by: Miroslav Ovcharik

Performance tuning is the tuning of an engine to increase the power output, torque, and responsiveness of the engine as well as the reliability and economy. To performance tune the engine, it must be strong enough to endure the extra power, sometimes far stronger than the standard engine. Also when Performance Tuning the car you must take into account the transmission, suspension and the brakes to make sure that these match the power output and torque of the engine as this will affect the overall performance of the car and make it more reliable and competitive. Most people want to increase the power output of an engine. The main way that is used to do this is to increase the rate and efficiency of combustion in an engine. This is achieved by putting more fuel/air mixture into the engine, using a fuel with higher energy content, burning it more rapidly, and getting rid of the waste products more rapidly – this increases volumetric efficiency. The specific ways this is done include:

• Increasing the engine displacement. This can be done by “boring” – increasing the diameter of the cylinders and pistons, or by “stroking” – using a crankshaft with a longer stroke (in combination with pistons of shorter compression height, to maintain the original compression ratio), or both.

• Using larger or multiple carburetors, to create more fuel/air mixture to burn, and to get it into the engine more quickly. In modern engines, fuel injection is more often used, and may be modified in a similar manner.

• Increasing the size of the valves in the engine, thus decreasing the restriction in the path of the fuel/air mixture entering, and the exhaust gases leaving the cylinder. Using multiple valves per cylinder results in the same thing – it is often more practical to have several small valves than have larger single valves.

• Using larger bored, smoother, less contorted intake and exhaust manifolds. This helps maintain the velocity of gases. Similarly, the ports in the cylinder can be enlarged and smoothed to match. This is termed “Cylinder head porting”, usually with the aid of an air flow bench for testing and verifying the efficiency of the modifications.

• The larger bore may extend right through the complete exhaust system, using larger diameter piping and low back pressure mufflers, and through the intake system, with larger diameter air boxes and high-flow, high-efficiency air filters. Muffler modifications will change the sound of the car’s engine, usually making it louder; for some tuners this is in itself a desirable property.

• Increasing the valve opening height (lift), by changing the profiles of the camshaft or the lift (lever), ratio of the valve rockers (OHV engines), or cam followers (OHC engines).

• Optimizing the valve timing to improve burning efficiency – usually this increases power at one range of operating RPM at the expense of reducing it at others. For many applications this compromise is acceptable. Again this is usually achieved by a differently profiled camshaft. See also Four-stroke cycle Valve Timing, variable valve timing.

• Raising the compression ratio, which makes more efficient use of the cylinder pressure developed and leading to more rapid burning of fuel, by using larger compression height pistons or thinner head gasket, or by milling “shaving” the cylinder head.

• Forced Induction; adding a turbocharger or supercharger. The fuel/air mass entering the cylinders is increased by compressing the air first, usually mechanically.

• Using a fuel with higher energy content or by adding an oxidizer such as nitrous oxide.

• Changing the tuning characteristics electronically, by changing the firmware of the engine management system (EMS). This chip tuning often works because modern engines are designed to give a great deal of raw power, which is then reduced by the engine management system to make the engine operate smoothly over a wider RPM range, with low emissions. By analogy with an operational amplifier, the EMS acts as a feedback loop around an engine with a great deal of open loop gain. Many modern engines are now of this type and amenable to this form of tuning. Naturally many other design parameters are sacrificed in the pursuit of power. The choice of modification depends greatly on the degree of performance enhancement desired, budget, and the characteristics of the engine to be modified. Intake, exhaust, and chip upgrades are usually amongst the first modifications made as they are the cheapest, make reasonably general improvements (whereas a different camshaft, for instance, requires trading off performance at low engine speeds for improvements at high engine speeds), can often improve fuel economy, generally don’t affect engine reliability much (because no moving parts are modified), and are in any case essential to take full advantage of any further upgrades.

• Manufacturer Detuned Engines – Changing the tuning characteristics electronically, by changing the firmware of the engine management system (EMS). This chip tuning also works because many manufacturers produce one engine which is used in a range of models and the power and torque characteristics are determined solely by the engine management system software. This allows the manufacturers to sell cars in various markets with different tax and emissions regulations without the huge development cost of designing different engines. Cross platform engine sharing also allows for a single engine to be used by different brands, tuned to suit their particular market.

Hi My name is Mitchel and I have been in the Automotive industry since 1991 having built my own performance cars during this time but I will go into more detail about this in my future articles!  by: Mitchel Sosa

BMW 318IS Coupe on work to be tune and modified. This car done a large tuning and modification.

Everybody wants to personalise the things that they use so that it makes their presence felt. Be it their car or any other gadget that they use, people prefer to add some kits or accessories to it to give it a personalised look. Car owners are a little more fortunate in this regard! The automobile market has plenty of options so far car accessories are concerned. One can make a choice as per his need and adorn his set of wheels.

There are accessories for both interior and exterior designing of a car. From the top to the tyres, there are options for all the parts of a car. By keeping roof boxes or roof racks on the top of the car, one can increase its capability for carrying luggage that cannot be accommodated in the trunk or the boot. In similar fashion, there are alloy wheels that make the car scintillating when it zings down the road swiftly.

Looking back to the inside, there are plenty of options to accessorise a car. Dash kits, seat covers, seat belts, gear knobs, pedal sets, leather gaiters, handbrake handles, and a lot more car accessories are there to adorn a car. However, one accessory that bears special importance is car mats. This is an integral part of any car. It serves dual purpose: keeping the floor safe and providing comfort to your feet.

It is not that car accessories are used for the purpose of stylizing a car or to make it more comfortable to drive. Some accessories are made by keeping the security side in mind. Adding these accessories to a car means ensuring higher security. What more, for the fair sex, specially made car kits are there. Pink has universal appeal to the girls. Hence manufacturers of auto accessories supply lots of kits in pink colours. Thus, there are options galore for all type of users.

by: Alexus Devon
http://directcaraccessories.co.uk

Here we can see the video on how the world BMW owner modified their car. This give you more idea if you want to do extreme modification for your BMW cars.