The way your tires wear is a good indicator of other parts of your car. Abnormal wear patterns are often caused by the need for simple tire maintenance, or for front end alignment. Tires should be inspected at every opportunity; once a week isn't too often. Learning to read the early warning signs of trouble can prevent wear that shortens tire life or indicates the need for having other parts of the car serviced. Tires should be inspected 3 ways. First, visually examine all 4 tires; second, feel the tread by hand to detect wear such as feathering and third, check all 4 tires with a pocket type pressure gauge.
	Over Inflation Excessive wear at the center of the tread indicates that the air pressure in the tire is consistently too high. The tire is riding on the center of the tread and wearing it prematurely. Many times, the "eyeball" method of inflation (pumping the tires up until there is no bulge at the bottom) is at fault; tire inflation pressure should always be checked with a reliable tire gauge. Occasionally, this wear pattern can result from outrageously wide tires on narrow rims. The cure for this is to replace either the tires or the wheels.
	Under Inflation This type of wear usually results from consistent under inflation. When a tire is under inflated, there is too much contact with the road by the outer treads, which wear prematurely. Tire pressure should be checked with a reliable pressure gauge. When this type of wear occurs, and the tire pressure is known to be consistently correct, a bent or worn steering component or the need for wheel alignment could be indicated. Bent steering or idler arms cause incorrect toe-in and abnormal handling characteristics on turns.
	Feathering Feathering is a condition when the edge of each tread rib develops a slightly rounded edge on one side and a sharp edge on the other. By running your hand over the tire, you can usually feel the sharper edges before you'll be able to see them. The most common cause of feathering is incorrect toe-in setting, which can be cured by having It set correctly. Occasionally toe-in will be set correctly and this wear pattern still occurs. This is usually due to deteriorated bushings in the front suspension, causing the wheel alignment to shift as the car moves down the road.
	One Side Wear When an inner or outer rib wears faster than than the rest of the tire, the need for wheel alignment is indicated. There is excessive camber in the front suspension, causing the wheel to lean too much to the inside or outside and putting too much load on one side of the tire. The car may simply need the wheels aligned, but misalignment could be due to sagging springs, worn ball joints, or worn control arm bushings. Because load has a great affect on alignment, be sure the car is loaded the way it's normally driven when you have the wheels aligned; this is particularly important with independent rear suspension cars.
	Cupping Cups or scalloped dips appearing around the edge of the tread on one side or the other, almost always indicate worn (sometimes bent) suspension parts. Adjustment of wheel alignment alone will seldom cure the problem. Any worn component that connects the wheel to the car (ball joint, wheel bearing, shock absorber, springs, bushings, etc.) can cause this condition. Worn components should be replaced with new ones. The worn tire should be balanced and possibly moved to a different location on the car. Occasionally, wheels that are out of balance will wear like this, but wheel imbalance usually shows up as bald spots between the outside edges and center of the tread.
	Second-rib Wear Second-rib wear is normally found only in radial tires, and appears where the steel belts end in relation to the tread. Normally, it can be kept to a minimum by paying careful attention to tire pressure and frequently rotating the tires. Some car and tire manufacturers consider a slight amount of wear at the second rib of a radial tire normal, but that excessive amounts of wear indicate that the tires are too wide for the wheels. Be careful when having oversize tires installed on narrow wheels.

article provided from www.procarcare.com

By design, the weight on the front and rear axles differs which causes uneven wear. With the majority of cars being front-engine cars, the front axle typically bears more of the weight. For rear wheel drive vehicles, the weight distribution between front and back approaches 50:50. Front wheel drive vehicles also have the differential in front, adding to the weight, with a typical weight distribution of no better than 60:40. This means, all else being equal, the front tires wear out at almost twice the rate of the rear wheels, especially when factoring the additional stress that braking puts on the front tires. Thus, tire rotation needs to occur more frequently for front-wheel drive vehicles.

Turning the vehicle will cause uneven tire wear. The outside, front tire is worn disproportionately. Cloverleaf interchanges, and parking ramps turn right in left hand drive (otherwise known as right hand traffic) countries, causing the left front tire to be worn faster than the right front. Furthermore, right turns are tighter than left turns, also causing more tire wear. Conversely the sidewalls on the right tire tends to be bumped and rubbed against the curb while parking the vehicle, causing asymmetric sidewall wear. The symmetric opposite occurs in countries that drive on the left.

In addition, mechanical problems in the vehicle may cause uneven tire wear. The wheels need to be aligned with each other and the vehicle. The wheel that is out of alignment will tend to be dragged along by the other wheels, causing uneven wear in that tire. If the alignment is such that the vehicle tends to turn, the driver will correct by steering against the tendency. In effect the vehicle is constantly turning, causing uneven tire wear. Also, if a tire is under or over-inflated, it will wear differently than the other tires on the vehicle. Rotating will not help in this case and the inflation needs to be corrected.

Car manufacturers will recommend tire rotation frequency and pattern. Depending on the specifics of the vehicle, tire rotation may be recommended every 12,000 km (7,500 mi). The rotation pattern is typically moving the back wheels to the front, and the front to the back, but crossing them when moving to the back. If the tires are unidirectional, the rotation can only be rotated front to back on the same side of the vehicle to preserve the rotational direction of the tires. Most unidirectional tires can be moved from side to side if they are remounted; tires with asymmetric rims are a rare exception. More complex rotation patterns are required if the vehicle has a full-size spare tire that is part of the rotation, or if there are snow tires.

To clarify; the pattern for asymmetrical tires to be rotated, or positioned, is for the tires on the driving axle of two-wheel drive vehicles to remain on the same side of the vehicle as they are moved to the non-driving axle, and for the tires on the non-driving axle to cross over to the opposite side of the vehicle as they are placed onto the driving axle. For All Wheel Drive (AWD) vehicles and Four Wheel Drive (4WD) vehicles, it is recommended that the tires from each axle cross over as the fronts move to the rear and rears to the front. For the 4WD configuration, it is dependent upon how much 4WD driving is actually performed, whether it's controlled via mechanical/computerized devices or in vehicle controls, the recommendation will likely be found in the Owner/Operator manual or can be obtained by speaking to the manufacturer or dealership.

Current thinking stresses the desirability of keeping the best tires on the rear wheels of the vehicle, whether it is front, or rear wheel drive. The reason for this is that if the rear wheels lose grip before the front ones, an oversteer condition will occur, which is harder to control than the corresponding understeer which will happen if a front wheel is lost. This is also the case if a tire blows out, so the intuitive belief that the front steering/driving tires need to be the best quality is not actually the case.

In rare cases, automobile manufacturers may recommend performing no tire rotation at all.

article provided from www.wikipedia.com

SEP 23 2009

Making the new Mercedes E-Class coupe even sportier and more exclusive is the goal of the extensive tuning program from BRABUS . The pinnacle of the available performance tuning is the BRABUS 6.1 displacement engine. It has a rated power output of 462 hp (456 bhp) / 340 kW and propels the E 500 (US: E550) to an impressive top speed of 315 km/h (196 mph). Also on offer is an aerodynamic-enhancement program that was developed in the wind tunnel. Further highlights are custom-tailored wheels up to 20 inches in diameter, sporty yet comfortable suspension solutions and exclusive interior options.

A rated power output of 462 hp (456 bhp) / 340 kW and a peak torque of 615 Nm (453 lb-ft) at just 3,100 rpm are the result of the displacement increase of the four-valve V8 engine from 5.5 to 6.1 liters. 0 - 100 km/h (62 mph) in 4.7 seconds and a top speed of 315 km/h (196 mph): The BRABUS 6.1 displacement engine turns the E 500 Coupe (US: E550) into a true high-performance automobile.

The displacement increase of the eight-cylinder engine sells for 29,000 Euros. It is facilitated by the installation of a billet-steel crankshaft with longer stroke and larger pistons. Furthermore the four-valve cylinder heads are precision-machined and fitted with custom camshafts. The BRABUS sport exhaust system with high-performance metal catalysts also contributes to the impressive power output as do specially programmed engine electronics.

More driving fun with the turbodiesel models is available with the BRABUS ECO PowerXtra kits. For the E 250 CDI BlueEFFICIENCY BRABUS offers its D4 tuning kit. For just 1,390 Euros power output of the common-rail four-cylinder engine jumps from standard 204 hp (201 bhp) / 150 kW to 235 hp (232 bhp) / 173 kW. Peak torque grows to 560 Nm (413 lb-ft).

The V6 turbodiesel engine of the E 350 CDI BlueEFFICIENCY equipped with BRABUS ECO PowerXtra D6 (III) module produces 272 hp (268 bhp) / 200 kW and a peak torque of 590 Nm (435 lb-ft).

All engines are lubricated with ARAL high-performance motor oil and like all BRABUS components they are backed by the one-of-a-kind BRABUS Tuning Warranty® of three years, up to 100,000 kilometers or 62,000 miles (see BRABUS warranty conditions as of November 2006).

Stainless-steel BRABUS quad sport exhaust systems are available for all new E-Class models.

The BRABUS designers have also developed a sporty yet elegant aerodynamic-enhancement package for the two-door E-Class. It is manufactured from Pur-R-Rim in OEM quality. The BRABUS front spoiler with integrated LED daytime running lights gives the coupe an even more striking face and reduces aerodynamic lift on the front axle at high speeds.

BRABUS adds sporty emphasis to the side view of the E-Class coupe with the new front aluminum sport fenders with integrated air vents. New rocker panels visually give the coupe a lower and sleeker stance. They feature LED entrance lights integrated into their undersides. Customers can also choose a version with integrated illuminated BRABUS logo.

The BRABUS rear apron features a centrally mounted reflector and custom-tailored cutouts on either side for the four tailpipes of the BRABUS sport exhaust system.

The exclusive BRABUS appearance is rounded out by one-piece or multi-piece BRABUS Monoblock light-alloy wheels with diameters of 17, 18, 19 and 20 inches. The largest tire/wheel combination features BRABUS Monoblock VI, E, Q or S wheels in size 9Jx20 on the front axle and in size 9.5Jx20 in back. BRABUS chose high-performance tires from Pirelli and YOKOHAMA in sizes 235/30 ZR 20 in front and up to 275/25 ZR 20 on the rear axle as the perfect complement.

The available BRABUS suspension solutions offer sporty handling combined with excellent ride comfort. They were custom-developed for the various engines available in the new E-Class. The list of options starts with lowering springs and culminates in a complete height-adjustable BRABUS coil-over sport suspension.

BRABUS also offers a high-performance brake system for the new Mercedes coupe. It features six-piston aluminum fixed calipers and 360-mm (14.2 inches) vented and cross-drilled discs on the front axle. The rear axle stops with four-piston aluminum fixed calipers.

BRABUS will customize the interior of the new E-Class Coupe to customers’ specifications. The list of interior options includes stainless-steel scuff plated with illuminated BRABUS logo, an ergonomically shaped BRABUS sport steering wheel and an entirely new interior crafted from especially soft yet durable BRABUS Mastik leather and Alcantara. New additions to the program are exclusive white genuine carbon-fiber inlays.

SEP 19 2009

The Ferrari Enzo with its 660 horsepower is arguably one of the most exclusive cars in the world, both in terms of its driving dynamics and purchase price. Those looking for something considerably faster and more exclusive choose the edo Enzo XX Evolution.

A bump in displacement from 6.0 to 6.3 liters, new camshafts, new titanium valve spring retainers and connecting rods, modified cylinder heads, new high performance exhaust headers, high flow catalytic converters, mufflers and air filters: that’s the scope of edo competition’s engine modifications. The standard hydraulic tappets are replaced with newly developed solid tappets, enabling the 12 cylinder engine to rev to an incredible 9,600 rpm. This is unmatched by any other 12 cylinder engine at this time! Additionally the intake system of the V12 was modified, a new high performance clutch - available with „strada“ or „pista“ friction pads - and a more powerful oil pump were installed. The power output is increased by 180 to 840 horsepower. Without mufflers more than 860 horsepower is possible. The maximum torque of 780 Nm (575 ft-lb) is available at 5,800 rpm.

While the power output is increased, the Enzo’s weight is decreased by a respectable 100 kilograms (220 lb). The result in numerical terms is that the edo Enzo XX Evolution accelerates from zero to 100 km/h (62 mph) in 3.2 seconds, 200 km/h (124 mph) in 9.0 seconds and 300 km/h in just 19 seconds. The top speed exceeds 390 km/h (242 mph).

The acoustical side of things is obviously not being neglected. A stainless steel muffler featuring remote-controlled butterfly valves is available on request. This setup lets the driver switch the high performance exhaust between two different sound levels.

Astonishing transmission shift times: While the production Enzo takes 110 milliseconds, the edo Enzo XX Evolution shift times were reduced to an incredible 60 milliseconds! For comparison, an F1 car shifts in 40 milliseconds.

The edo/KW race suspension from the FIA GT series was retuned for the Enzo XX Evolution, promising ultimate driving dynamics. The nose lift functionality is retained. The low-friction 3-way adjustable shock absorbers can be adjusted to the individual tastes of the driver and provide excellent steering precision and feedback. The edoinstalled tire pressure monitoring system displays the pressures for each of the four wheels. Providing ample grip for the edo Enzo XX Evolution are 19 inch front wheels and 20 inch rear wheels with 335 mm wide tires. The drive shafts were replaced due to the higher propulsive forces acting on them. The new units are 4 kg (8.8 lb) lighter and considerably more robust in order to cope with the enormous power increase.

The aerodynamics package is absolutely unique.

It includes a complete exhaust system with tips machined from billet aluminum, now relocated to the top of the body. The tips are plasma-coated using a special process. The newly developed rear skirt featuring winglets and a rear wing profile, adjustable in 3 steps, improves the ground effect and can be tuned to the tastes of the driver. The new retractable rear wing is upgraded with a taller flap resulting in increased downforce and stability, especially at high speeds. New LED tail lights round off the rear view of the car.

July 18 - 2009 Bentley Continental Supersports at Goodwood 

The Bentley Continental Supersports, the fastest and most powerful car in the companys 90-year history, received the ultimate examination of its supercar handling and performance credentials when Le Mans racing legend and honorary Bentley Boy Derek Bell spent the weekend driving the 621bhp Bentley at pace during the Goodwood Festival of Speed.