Automotive Engineering I

Student Name:                                                                               Student Class No.:

1-A) Find the tire radius from this reading:

            P215/65R14 80U

 

 

 

 

 

B) Explain how to determine the tire static radius.

 

 

 

 

 

C) Which is faster and show why?

            A- a) a tire with rolling radius 0.32 m or  b) a tire with a rolling radius of 0.36 m.

           

 

 

 

            B- a) the outer wheel or  b) the inner wheel, while the car is negotiating a curve.

 

 

 

 

2- Explain:

A) What is meant by:

            a) Tire height:

            b) Tire aspect ratio:

            c) Speed markings:

           

B) Why there are:

            a) Splines (telescopic joint) in the propeller shaft:

            b) Crown and pinion final drive gears:

            c) Tubeless tires: 

 

 

 

 

3- A) Write down the types of final reduction and the advantage of each type

	Type of final reduction	Advantages
1
2
3

 

B) Write down the types of tire radii and show how you can obtain each one of them

	Type of tire radii	Method of obtaining them
1
2
3

 

4- A) Complete the following table, if the maximum engine power is 80 kW at 6000 rpm, and the tire radius is 0.32 m and the final drive ratio is 4.05.

Ne (rpm)	2000
Nw (DD)
V (km/h)
Pb (kW)
Tw (N.m)

 

P_b = P_b(max) [(N_e/N_b(max)) + (N_e/N_b(max))² - (N_e/N_b(max))³]

T = 9550 P_b/N

 

B) A vehicle in second gear, which has the ratio 2.68:1, the engine producing a torque of 1260 at the wheel axle, while the engine is developing  a torque of 125.7 Nm at 2200 rpm. Assuming a transmission efficiency of 79%. Determine

i- the final drive ratio

ii- the wheel speed in rpm.