From GICL Wiki
Revision as of 23:30, 15 December 2009 by MAE277 34 09 (Talk | contribs)

(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search

Dissection Plan

Given several factors, we decided that it would be most effective to start the dissection process as soon as possible and will have our first session the following Wednesday. Given the size and complexity of the product, we plan on completing the dissection in two parts over two weeks in the two lab hours on Wednesdays. This gives us two extra lab hours to complete the dissection in order to make up in case of any delays leading up to the second gate.

Given that our Technical Experts have had prior experience with car engines and a strong knowledge of tools and hardware, they were able to write up an accurate list of tools required for the disassembly. They are as follows:

  • Socket Wrench Set with Sockets, Deep Sockets and Wrench Extensions.
  • Allen Keys.
  • Pulley Puller.
  • Valve Spring Compressor.

The Product: Initial Product Assessment

Uses: The product that was given to our group for reverse engineering was a GM Vortec 4300 V6 Car Engine. The intended use of this model specifically is to drive cars although other types of internal combustion engines can be used for many other applications in industry and other vehicles. The product can be used for either home or professional use and its function is to convert the chemical energy from the fuel to mechanical energy that is used to drive the car.

Method of operation: The product works by igniting fuel and pressurized gas inside a chamber which then causes the combustible substances to push against the moving parts of the engine. Specifically, the fuel injectors allow a mixture of air and gasoline to enter the cylinder. The piston inside the cylinder then compresses the mixture which is then ignited by the spark plug causing the piston to shoot back out. The pistons move the camshaft which in turn drives the car. The energies used are purely chemical (i.e. contained in the air and gasoline) and are then converted into Heat and Mechanical Energy. While the intent is only to produce Mechanical Energy, Heat is a by-product of the inherent inefficiency. As explained above the operation of the engine allows it to convert Chemical Energy to Mechanical Energy and Heat (which is discharged through the exhaust and the surroundings of the engine itself). The product itself is not currently functioning, thus making it difficult to assess any of its problems.

Components: The model is a GM V6 engine with several components. These are:

  • Camshaft
  • Crank
  • A timing chain
  • 2 Heads/ Valve covers
  • 6 Rods
  • 6 Pistons
  • 12 Lifters
  • 12 Rocker Arms
  • 12 Pushrods
  • 12 Valve Springs
  • Upper and Lower Air intakes
  • Oil Pump and Oil Pan
  • Throttle Body

Complexity: Looking at each of these individual parts, they are not in themselves complex, but on a whole, the engine can be said to be around a 5 on a scale of 10. The reason for this is that we have defined complexity as a whole on the basis of moving parts and the number of components. In order to judge complexity, we only compared it to other car engines and not to other larger engines used for other applications. For a better idea, the engine in a Lamborghini (which has 4 overhead cams, 12 cylinders and 4 valves per cylinder) would be placed at 10, whereas a carbureted 4-cylinder configuration (without multi-port fuel injection) would be placed at a 1.

Materials Analysis: The Materials used in the product are primarily Cast Iron, Cast Aluminum and Stainless Steel. Other materials include rubber for the timing chain and plastic for the covers on the Valve and Cylinder heads. Given our group’s prior knowledge on car engines, we estimate that there are no other significant materials in the engine.

End User Satisfaction: When comparing the product to other equivalents V6 motors of the mid 1990’s, the Vortec outclassed other engine models due to its high fuel efficiency and its sizeable 3.8L power. Thus, we can say that end users would be quite happy with the product as a whole. Given that it is in itself a component of a car and being used indirectly by the end user, we cannot comment on its ergonomics and its ease-of-use. The regular maintenance that the end user performs would be to change the oil every 3000 miles. This does not reflect the maintenance required on a car however, just the engine itself. Anything beyond the said oil change would require professional knowledge from a certified technician.

Alternatives to the product: When trying to find other alternatives to the product, we cannot limit the criteria to the engine alone as such information would not be useful. Factors such as cost would depend on specific cases depending on any modifications to the engine itself. Therefore, we can try and compare the alternatives from a user’s point of view i.e. by comparing the cars that incorporated the Vortec 4300 and comparing them to other models in the same power class of these cars.

Various models (Chevy Astro Van, GMC Safari, GMC Jimmy, Chevy Blazer, Oldsmobile Bravada, etc) used the Vortec 4300. All of these vehicles were in the price range of $22,000 and $25,000. The alternatives were:

  • The Ford Explorer: $22,000
  • The Toyota 4runner: $25,000
  • The Mitsubishi Montero:$26,000
  • The Jeep Cherokee:$23,000
  • And the Nissan Pathfinder:$30,000

As mentioned earlier, the Vortec 4300 outclasses these models in terms of fuel efficiency and power so it was also in comparison value for money to the end user. However, despite having a track record of very few reliability issues the Nissan Pathfinder has even less Reliability issues.

Gantt Chart

The Gantt chart below shows the progress of the tasks that the group needed to do in order to complete the reverse engineering project. It shows the start and end dates of each gate as well as a reference to these dates on the left hand side.