Race Car Gear Box

RE-DESIGN OF A RACE CAR GEARBOX
Re-design of a Race Car Gearbox

Mechanical Design 2 EML 4905
Your task is to redesign a gearbox for a BMW M6 GT3 race car competing in the GT World Challenge.
The gearbox used in the car is a Ricardo custom-built Gearbox. It has a compound reverted gear train
type design and it is a 6-speed gearbox.
The gear ratios (Number of Teeth) are as follows:
1st Gear 13:37

2nd Gear 17:38
3rd Gear 17:31
4th Gear 19:29
5th Gear 23:30
6th Gear 21:24
Final Drive 16:44 (CAN’T CHANGE)
The engineers at BMW Motorsports noticed that the car was missing top speed compared to its
competitors and the gear ratios were not appropriate for every track.
GOAL OF THE PROJECT
Your goals are to design a new gear train in order to:
(1) Increase the top speed of the car by 7%.

(2) Enhance vehicle acceleration from 0 to 130 mph – you do not have to necessarily find the
acceleration of the vehicle but your design should improve this parameter. Think about what
metrics you can use to measure an increase in acceleration.
REMINDER: YOU NEED TO KEEP ALL YOUR GEARS ON THE 2 SHAFTS FROM YOUR GEAR TRAIN AS
SHOWN BELOW
Constraints
 This means that you will be constrained in size from gear 1 to 6.

 Your gear designs should fit in a window of 21 inches by 21 inches. (depth is not an issue)
 Your pairs of gears all have to be fitting on the two shafts and interchangeable
 You do not have to design the sliding mechanisms or how the gears will switch from one to
another.
 You can design your gears as spur gears as this is what is currently used on the Ricardo
gearbox
 The maximum engine speed is 6500 rpm
 You will have to design for safety factors of 1.3 in bending and 1.1 in contact
 Car Weight: 1315 kg
Required for report
Report on what changes were made and why for the two goals shown above. Show why you made
your design decisions.
Full calculation of stress analysis and safety factors for each gear pair (try to automate the process)
Show all your design decisions and results for your final gear geometry, material selection, all factors
we discussed in class.
Attach any code you used or your calculation worksheets for the project.
Please consider your audience and write the report to a general engineer. Do not assume they have
any knowledge of the challenges you have been asked, or any specific knowledge of the scientific
methods that you are using. You can assume general knowledge of stress/strain and simple
engineering concepts. Please do not write directly to me or include my name in any capacity in the
report, nor should you include any information that this report was written for a course or achieve a
grade, I am an evaluator of the report, not the directed audience.
RUBRIC
– Formatting/Clarity: 40%
– Scientific Foundation: 40%
– Scientific Discussion: 20%
Grading will be completed by assessing your ability to accurately and clearly describe the steps that
you took to completing your design. All students are required to discuss their results in a scientific
manner and include the changes made from baseline and what results were achieved, what lessons
were learned and what outcomes can be obtained from the project. The report is open ended, it is
expected that students will include the information that they find important and omit sections that
do not add to the discussion.
Some extra information you will need for designing the gear train
Torque and Power Curves
Torque and Power Curve for M6 GT3

700
600
500
400
300
200
100
0
0 1000 2000 3000 4000 5000 6000 7000
Torque (ft.lbf) Power (hp)
RPM Torque Power (hp)

(ft.lbf)
2500 240 114
3500 350 233
4500 440 377
5000 480 457
5500 498 522
6000 498 569
6500 470 582
Tyre Information
Make and Model: Pirelli P-Zero DHE
Slick Tyre 325/705-18
Extra credit (Extra 10% on Report)
Create a car acceleration simulator on MATLAB to simulate your time to do 0-62.5 mph and 0-
150mph using your new gearbox.
Things you will need to complete this:
Aerodynamic drag, Cd = 0.36
Frontal Area = 2.3 square meters
Make any assumptions that you need to complete this and state them clearly. For example:
assume the road is flat for this acceleration test.
Grading Rubric for extra credit
Complete and Working Simulator: 10%
Satisfactory Simulator with some errors: 5%
Attempt at making a simulator but incomplete: 0%

Race Car Gear Box

Uploaded by

Copyright:

Available Formats

Race Car Gear Box

Uploaded by

Document Information

Original Description:

Copyright

Available Formats

Share this document

Share or Embed Document

Sharing Options

Did you find this document useful?

Is this content inappropriate?

Copyright:

Available Formats

Race Car Gear Box

Uploaded by

Copyright:

Available Formats

RE-DESIGN OF A RACE CAR GEARBOX

Re-design of a Race Car Gearbox

The gear ratios (Number of Teeth) are as follows:

1st Gear 13:37

GOAL OF THE PROJECT

Your goals are to design a new gear train in order to:

(1) Increase the top speed of the car by 7%.

 This means that you will be constrained in size from gear 1 to 6.

Required for report

– Scientific Foundation: 40%

– Scientific Discussion: 20%

Torque and Power Curves

Torque and Power Curve for M6 GT3

Torque (ft.lbf) Power (hp)

RPM Torque Power (hp)

Make and Model: Pirelli P-Zero DHE

Slick Tyre 325/705-18

Extra credit (Extra 10% on Report)

Things you will need to complete this:

Aerodynamic drag, Cd = 0.36

Frontal Area = 2.3 square meters

Complete and Working Simulator: 10%

Satisfactory Simulator with some errors: 5%

Attempt at making a simulator but incomplete: 0%

You might also like