- •Передмова
- •Lesson 1
- •Reading Exercises:
- •Speaking Exercises:
- •III. Writing exercises:
- •Lesson 2
- •Dohc or Twin cam engine
- •After text activity
- •I. Reading Exercises:
- •II. Speaking Exercises:
- •III. Writing exercises:
- •Lesson 3 Read the text: springs
- •I. Reading Exercises:
- •II. Speaking Exercises:
- •III. Writing exercises:
- •Lesson 4
- •I. Reading Exercises:
- •II. Speaking Exercises:
- •III. Writing exercises:
- •Lesson 5
- •Lithium-Ion Car Battery
- •I. Reading Exercises:
- •II. Speaking Exercises:
- •III. Writing exercises:
- •Lesson 6
- •I. Reading Exercises:
- •II. Speaking Exercises:
- •III. Writing exercises:
- •Lesson 7
- •I. Reading Exercises:
- •II. Speaking Exercises:
- •III. Writing exercises:
- •Lesson 8 Read the text: Servicing the Engine Cooling System
- •I. Reading Exercises:
- •II. Speaking Exercises:
- •III. Writing exercises:
- •Lesson 9
- •I. Reading Exercises:
- •II. Speaking Exercises:
- •III. Writing exercises:
- •Lesson 10
- •I. Reading Exercises:
- •II. Speaking Exercises:
- •III. Writing exercises:
Dohc or Twin cam engine
DOHC or Double OverHead Cam - the setup used in many today's cars. Since it's possible to install multiple valves per cylinder and place intake valves on the opposite side from exhaust vales, DOHC engine can "breath" better meaning that it can produce more horsepowers with smaller engine volume. Compare: The 3.5-liter V6 DOHC engine of 2003 Nissan Pathfinder has 240 h.p, similar to 245 h.p of the 5.9-liter V8 OHV engine of 2003 Dodge 4-cylinder 16 valves DOHC engine Durango. Pros: High efficiency, possible to install multiple valves per cylinder and adopt variable timing. Cons: More complex and more expensive design.
After text activity
I. Reading Exercises:
Exercise 1. Read and memorize using a dictionary:
camshaft; dependent variable; efficiency; in the opposite direction; in the opposite order; independent variable; inertia; intake; on the opposite side; OverHead pushrod; random variable; rocker arm; variable. |
Exercise 2. Answer the questions:
What does OHV engine design mean?
Where is the camshaft installed in SOHC engine?
What is the disadvantage of an OHC engine?
Exercise 3. Match the left part with the right:
1. OHV means OverHead Valve - an engine design where |
a) is installed in the cylinder head. |
2. In the SOHC engine the camshaft |
b) "breath" better meaning that it can produce more horsepowers with smaller engine volume. |
3. OHC engine requires |
c) the camshaft is installed inside the engine block and valves are operated through lifters. |
4. Double OverHead Cam engine can |
d) has been successfully used for decades. |
5. Although an OHV design is a bit outdated, it |
e) a timing belt or chain with related components. |
Exercise 4. Open brackets choosing the right words:
DOHC or Double OverHead Cam - the setup (got/used) in many today's cars. Since it's possible to install multiple valves per cylinder and (feel/place) intake valves on the opposite side from exhaust vales.
II. Speaking Exercises:
Exercise 1. Describe intake valve; camshaft; rpm; cylinder; horsepower using the suggested words and expressions as in example:
intake valve metal; a rod; a flat disc; intake passage; cylinder head example:Intake valve is a metal valve that looks like a rod connected to a flat disc that opens/closes the intake passage in the cylinder head. |
camshaft inside an engine; lobes; engine's valves; "pushrod" engines; cam lobes; the up and down motion; rocker arms; to actuate the valves |
rpm abbreviation; revolutions; per; minute; engine speed; expressed as; |
cylinder a chamber; within; piston; to move |
Horsepower a unit of measure; power output; James Watt; a horse; the amount of effort; in one minute; after internal friction |
Exercise 2. Ask questions to the given answers:
1) Question: ___________________________________________ ?
Answer: OHV means OverHead Valve - an engine design where the camshaft is installed inside the engine block.
2) Question: ___________________________________________ ?
Answer: OHV engine is also known as "Pushrod" engine.
3) Question: ___________________________________________ ?
Answer: OHC in general means OverHead Cam while SOHC means Single OverHead Cam.
4) Question: ___________________________________________ ?
Answer: Double OverHead Cam engine can "breath" better meaning that it can produce more horsepowers with smaller engine volume.