Archive for May, 2011

Subaru Impreza WRX STI Engine

Posted on May 30, 2011 | Automotive Repair.

The introduction of the Impreza line began with Subaru in 1993. Subaru’s main goals when producing this vehicle were to help fill a gap in the small car market initially; later in its life Subaru changed its goals to become dominant in rally race scenes. The power to weight ratio of the Impreza when a combination of the fairly small, light chassis and the boxer styled four cylinder Subaru engine made it instantly successful in the rally races. Each year brought new revisions to the Subaru engines, ramping up power while still keeping the lighter chassis making it a dominating force when on the track.

The first versions of the Impreza were offered in either front wheel drive or an all wheel drive configuration. It was available in either a four door sedan or a five door station wagon/estate. Initially the Subaru engine offered was a 1.8 flat 4 cylinder known as the EJ18. This was followed quickly with the addition of the 1.6 litter version. Subaru chose to stay with the same basic design of the engine known as the flat four cylinder (or boxer) engine as they believed that by keeping the engine on a low centre of gravity, in line with the transmission, minimised body roll as compared to vehicles with offset engines. Another bonus to this design is that it also eliminated the need for a weighted counter rotating crankshaft. Since each piston is counter weighted by the opposing piston directly opposite while the engine is running. The 1.6 and 1.8 engines were dropped from production in 1996 and replaced with the now common 2.0 litre.

Subaru then introduced the STI(Subaru Technica International) version of the Impreza into the Japanese Domestic Market or JDM as it is more commonly known, in 1994. The STI was an upgraded version of the Impreza WRX models currently available. The STI came equipped with performance tuned suspensions, engines and transmissions. The STI was immediately successful in rallies and was sought after by street racers. There was even an option to order special RA (Race Altered) versions direct from the manufacturer which were modified by being lighter in weight, having reduced sound proofing, manual window mechanisms, omitting the air conditioning and coming equipped with more robust engines, shorter gearing and driver controlled center differentials.

The Impreza model received an external facelift in 1997, this was followed by an internal redesign incorporating the more advanced dashboard from the Forester in 1998. Further upgrades were found on the European models in 1999-2000. These upgrades included making parts from the STI range standard, front brake callipers were now four pot with 294mm brake discs, wheels were upgraded from 15 inch to 16 inch, they added vented rear disc brakes, a firmer suspension and bucket seats.

The beginning of 2001 saw the introduction of the second generation of the Subaru Impreza. The body style was larger, safer, more refined, the suspension was stiffer and more responsive. Many Subaru owners use nicknames for their vehicles based on the headlights they came with. In 2002-2003 the headlights became known as “bug eyes”, these were followed in the 2004-2005 “crocodile eye” versions also known as “blob eyes” and then finally in 2006-2007 the headlight configuration was to be known as “hawk eyes”.

Used F250 6.0 Turbo Diesel Engine

Posted on May 27, 2011 | Automotive Repair.

Everyone is aware that the Ford Motor Company has been one of the most respected automotive companies of the world for the last 50 years. Among other things, the company is engaged in manufacturing full size pickup trucks also. Among the F series pickup trucks, the aim of launching F 250 is to bring out a truck with great features, design, power and specifications. F 250 are the Super Duty Pickups launched by Ford.

F 250 trucks are quite popular for their creditable torque capacities, towing rating and also for their payloads. The performance levels of the engines of F 250 trucks are much more than those of F 150 trucks. In general, all pickup truck drivers may wish to have enhanced boost for pay loads and this desire is completely fulfilled in these trucks with a great engine power.

The Ford F-250 6.0L engine has a long life as is the case with all diesel engines. This is a Power stroke engine with an overhead valve design. Each cylinder has four valves. This is an iron block motor with an electro-hydraulic “generation 2″ fuel injection, otherwise called the Split Shot Hydraulic Electronic Unit Injectors system (HEUI). The compression ratio of this engine is 18.0:1. The horsepower produced by this V 8 engine is 325 at 3,300 rpm and the torque is 570 lb.ft. at 2,000 rpm. The measurements of bore and stroke are 3.74 inches by 4.13 inches. There are two options in transmission, with both six-speed and five-speed automatic transmissions available. Options of both four-wheel drive as well as a two-wheel drive are available. The maximum payload and the gross vehicle weight rating of this 6.0 liter are 2,700 lbs. and 9,600 lbs. respectively. The steering used is power recirculating ball steering with an overall ratio of 20.16:1. The engine uses a variable geometry turbocharger and intercooler. The turbo configuration is Single Variable Vane Geometry, otherwise called as the VGT Configuration.

The 6.0 Power Stroke engine was first used in the year 2003 and it was a replacement to the previous the 7.3 liter engine. At the time of launching, it produced a horsepower of 325 and a torque of 560 lb.ft. In the year 2005, the company modified the 6.0 L 32-valve pushrod-actuated Power Stroke single-turbo diesel engine and the torque was boosted to 570 lb.ft. But, there was no change in the power of the engine.

This engine was used on super duty trucks till model year 2008 which ended in 2009. The previous 6.0 liter engines that were used prior to 2003 were totally unreliable. In fact, the company was said to have incurred huge losses due to them because many users opted for warranty repairs. There were many recalls also. So, the company resorted to a huge rectification process and the suitable modifications were effected from model year 2005, after which the reliability of these 6.0 L engines has been terrific. The design modifications done were excellent, thanks to the intensive training given to the technicians.

The 6.0 liter engine also faced the EGR valve carbon deposit issue. The problem was that the valves had to be replaced due to clogging of carbon in them and this used to happen during the powertrain warranty period. The company conducted serious research about this and found that extended idle times were responsible for the carbon buildup. The factor behind this was that the combustion efficiency of diesel engines at idle speeds was usually low. By updating the programming of the powertrain control module, the company could solve this issue.

When you opt to buy a used F250 6.0 Turbo Diesel engine for your vehicle, you should search with patience or otherwise, you run the risk of choosing a wrong engine. It is not that you should approach this issue with a dose of skepticism but you should adopt utmost caution. Choosing the right dealer who can guide you properly and having your own mechanic along with you for inspecting the engine are the right prescriptions for having the right motor for your vehicle.