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Here is a Set Up Guide for Forza 2
created by Feuerdog,for individual
set ups please use the links on the left.
Forza Motorsports 2
Suspension Setup Calculator
Version 2
by Feuerdog
INTRO - The new physics modeling of FM2 has changed the realism and overall feel from FM1. In order to take advantages of the new physics, a new guide with new calculations needed to be written. Improvements have been made in the guide, just as in the sim. Hopefully these new suspension setup calculations will provide you with a car that handles better, is esier to drive, and faster too. Enjoy!
PURPOSE - Why use this guide?
- What it might do you for you
- help drivers and tuners by giving them a way to tune or retune thier own cars without having to understand all the definitions and relationships within a suspension setup.
- To possibly improve the performance of a car that is troublesome to drive and/or tune .
- To provide an easy way to establish a baseline tune from which more advanced tuning can be done.
- What it won't do for you
- It is not intended to explain why or how everything works, independantly or as a whole, but it might provide some useful information.
- No two cars, drivers, tracks, or setups will act exactly the same. Your results will be subjective and will vary.
- These calculations will not acheive a perfect tune, but they may be an improvement, or at least an alternative.
- This is NOT an ultimate setup guide. You can improve these tunes further. I do.
MY DRIVING STYLE - Do we drive the same way?
The same tune that works for one driver doesn't always work well for other drivers. In order for you to understand why the tune from this guide will handle the way it does, it helps to understand the way that I drive and what characteristics I look for.
- I use a standard controller(sometimes the wheel and pedals), with trigger brake, trigger throttle, and stick for steering.
- No assists usually except for ABS. In car view. Auto transmission.
- I memorize physical objects like signs, walls, barriers, and curbs to mark where my braking and turn-in points are.
- I like my tunes to be stable, balanced, and easy to drive.
- I like moderate spring, stiff damper setups.
- I tend to brake hard and straight at first, and then transition into a trail-braking turn-in. I then transition into full acceleration from apex to exit.
- I prefer on-throttle, and throttle lift oversteer characteristics.
- I usually use the same tune for every track, but there are always exceptions.
- I am not the greatest driver, but I manage to have fun.
REALISM - Keeping it real.
I have tried to tune my cars based, for the most part, on reality. If the physics of Forza are realistic, then realistic values should work in the sim, and they do, which is a good thing. The Turn 10 team did very well. Tuning and testing in a realistic way adds to the enjoyment of the whole simulation for me. Therefore, I have gone to some lengths to keep my tuning based on "real world" values and ratios. I have actually spent alot of time, and some money, to learn more about damping, automotive vehicle dynamics, and racing car tuning in general. In the end it's all about fun. If this guide can provide you with a car that is fun and easy to drive then my work here is done.
SUSPENSION SETUP CALCULATOR
Scroll down to GREEN section for automatic calculators.
1. Before you begin.
2. Springs, Dampers, and Antiroll Bars
- Springs
- Antiroll Bars
- Dampers
- Bump Stiffness
- Rebound Stiffness
3. Alignments
- Camber
- Toe
- Caster
4. Tires
5. Brakes
6. Differentials
1. BEFORE YOU BEGIN -
1.1 - You need....
- to have....
a. A basic calculator, a pencil, and something to write on.
b. A car with a Race suspension, Race brakes, Race Springs and Dampers, and a Sport or Race Differential.
- to know....
a. The weight of the car, and what the weight distribution values are for front and rear. These are found in the game.
b. Any changes to the weight of the vehicle will mean you have to recalculate the values.
c. These settings assume the use of ABS, with NO TCS, and NO STM! There is a good chance your car won't handle very well with these assists enabled.
d. These abbreviations:
AWD = All wheel drive
FWD = Front wheel drive
RWD = Rear wheel drive
FF = Front engine, Front wheel drive
FR = Front engine, Rear wheel drive
FA = Front engine, All wheel drive
MR = Mid engine, Rear wheel drive
MA = Mid engine, All wheel drive
RR = Rear engine, Rear wheel drive
RA = Rear engine, All wheel drive
Understeer - the car doesn't turn easily
Oversteer - the car turns too easily
2. SPRINGS, ANTIROLL BARS, and DAMPERS -
2.1. Find the weight multiplier -
a. Get the weight of the car from the garage screen.
b. Multiply the weight of the car by .3
c. This is your weight multiplier - write this number down.
Example FF car: 2600 lbs x .3 = 780
Advanced Tuning - To stiffen the suspension multiply by .32, to soften the suspension multiply by .28
2.2. Find the modified weight distribution -
a. Get the weight distribution values for the car.
Example FF car: 57% front/43% rear
b. Calculate the cars modified weight distribution values by altering the stock weight distribution using the following table:
FF = subtract 8% from the front, and add 8% to the rear.
FR = add 8% to the front, and subtract 8% from the rear.
FA = subtract 4% from the front, and add 4% to the rear.
MR = add 2% to the front, and subtract 2% from the rear.
MA = no change.
RR = add 2% to the front, and subtract 2% from the rear.
RA = add 1% to the front, and subtract 1% from the rear.
Example FF car: 57% front (-8%)/43% rear (+8%) = 49% front/51% rear
c. These modified percentages are your modified weight distribution - write this number down.
2.3. Find the Spring settings -
a. Weight multiplier x modified weight distribution = Spring value - enter these settings.
Example FF car:
- 780(weight modifier) x .49(49% modified front weight distribution) = 382 Front Springs
- 780(weight modifier) x .51(51% modified rear weight distribution) = 397 Rear Springs
Advanced Tuning - You may need to adjust your ride height. Lower is better, but too low may cause excessive bottoming out. Adjust as needed.
2.4. Find the Antiroll Bar settings -
a. Weight distribution x 25 = AntiRoll Bar settings - enter these settings.
Example FF car:
- .57(front weight distribution) x 25 = 14.2 front AntiRoll bar
- .43(rear weight distribution) x 25 = 10.7 rear Antiroll bar
Advanced Tuning - For stiffer Antiroll Bars multiply by 35, for softer Antiroll Bars multiply by 15
2.5. - Find the damper Bump Stiffness -
a. (Spring value + 200) x .011 = Bump Stiffness - enter these settings.
Example FF car:
- (382 front springs + 200) x .011 = 6.4 front Bump Stiffness
- (397 rear springs + 200) x .011 = 6.5 rear Bump Stiffness
Advanced Tuning - For stiffer dampers multiply by .012, for softer dampers multiply by .010
2.6 - Find the damper Rebound Stiffness -
a. Get the Bump Stiffness values for the car.
Example FF car:
- 6.4 front Bump Stiffness
- 6.5 rear Bump Stiffness
b. Calculate the cars Rebound Stiffnessvalues with the following table:
FF - Front Bump stiffness x 1.5 = Front Rebound Stiffness
FF - Rear Bump stiffness x 1.1 = Rear Rebound Stiffness
FR - Front Bump stiffness x 1.1 = Front Rebound Stiffness
FR - Rear Bump stiffness x 1.5 = Rear Rebound Stiffness
FA - Front Bump stiffness x 1.5 = Front Rebound Stiffness
FA - Rear Bump stiffness x 1.1 = Rear Rebound Stiffness
MR - Front Bump stiffness x 1.2 = Front Rebound Stiffness
MR - Rear Bump stiffness x 1.3 = Rear Rebound Stiffness
MA - Front Bump stiffness x 1.3 = Front Rebound Stiffness
MA - Rear Bump stiffness x 1.2 = Rear Rebound Stiffness
RR - Front Bump stiffness x 1.3 = Front Rebound Stiffness
RR - Rear Bump stiffness x 1.4 = Rear Rebound Stiffness
RA - Front Bump stiffness x 1.4 = Front Rebound Stiffness
RA - Rear Bump stiffness x 1.3 = Rear Rebound Stiffness
Example FF car:
- 6.4(front bump stiffness) x 1.5 = 9.6 front Rebound Stiffness
- 6.5(rear bump stiffness) x 1.1 = 7.1 rear Rebound Stiffness
Advanced Tuning -
- Increase corner entry oversteer OR Decrease corner entry understeer = Subtract .1 from the rear Rebound Stiffness multiplier, and recalculate.
- Increase corner exit oversteer OR Decrease corner exit understeer = Add .1 to the front Rebound Stiffness multiplier, and recalculate.
- Increase corner entry understeer OR Decrease corner entry oversteer = Add .1 to the rear Rebound Stiffness multiplier, and recalculate.
- Increase corner exit understeer OR Decrease corner exit oversteer = Subtract .1 from the front Rebound Stiffness multiplier, and recalculate.
- For faster weight transitions lower both of the multipliers by .1
- For slower weight transitions increase both of the multipliers by .1
3. ALIGNMENTS -
3.1. Set Camber -
a. Set camber to -.8 Front/-.8 Rear
b. Adjust camber based on aerodynamic downforce.
- +.1 camber per 200lbs downforce
Example R4 car with 150lbs front/300lbs rear
- 150lbs front downforce = -.8(front camber) + .0 = -.8 front camber
- 300lbs rear downforce = -.8(rear camber) + .1 = -.7 rear camber
3.2. Set Toe -
FF = .1 front/.1 rear
FR = .0 front/-.2 rear
FA = .1 front/.1 rear
MR = .1 front/-.1 rear
MA = .1 front/0 rear
RR = 0 front/-.2 rear
RA = 0 front/-.1 rear
Advanced Tuning - Increase front positive toe to improve turn-in response, decrease to improve stability. Increase rear negative toe to improve rear stability, decrease to reduce understeer.
3.3. Set Caster -
Set caster to 5.5
Notes: I don't want to get into the details of caster tuning, but it is very closely related to front camber settings, and it shouldn't be adjusted out of the 5.6~6.0 range while used with the other settings. 5.5 caster adds approx. 3 degrees of dynamic camber to the front wheels at full steering lock.
4. TIRES -
4.1. Set Tire pressures
Set all tires to 29psi(2.0bar)
Advanced Tire Pressure tuning -
1. Free Run five or more laps of Tsukuba.
2. Watch the telemetry screen for tire pressures.
3. Note the pressure increase of the left side tires from lap one to lap five.
4. Adjust the tire pressures front and/or rear "down" so that the tire heats "up" into it's best operating pressure and/or temperature.
5. BRAKES -
5.1. Set Brake Force
a. Set brake force to 110% with ABS, or 90% without ABS.
5.2. Set Brake Balance
a. Set brake balance to 47% front
Advanced Tuning -
- Adjust force in +/-5% increments for best feel or benchmark performance.
- Adjust balance in +/-2% increments for best feel, stability, or benchmark performance.
6. DIFFERENTIALS -
- FWD = 40% Accel./0% Decel.
- RWD = 65% Accel./55% Decel.
- AWD Front = 30% Accel./0% Decel.
- AWD Rear = 80% Accel./70% Decel.
- AWD Split = 25% Front/75% Rear
Note: Gearing, power, and torque won't directly how the diff. work but they will changes the feel of it's effects. Keep this in mind while tuning.
Advanced Tuning -
Accelerating oversteer?
- Adjust rear diff. = -5% Accel.
Accelerating understeer?
- Adjust front diff. = -5% Accel.
Braking oversteer?
- Adjust diff. = +5% front Decel. OR -5% rear Decel.
Braking understeer?
- Adjust front diff. = -5% Decel. OR +5% rear Decel.
Automatic calculators -
It seems there are some fans of my calculator who are just as dedicated as I am to having fun and making life easier. Below is a selection of spreadsheet and webpage calculators that have been made using the calculations above. These fantastic tools take all the hassle out of the calculator and puit it in an easy to use format, enjoy!
If there are corrections or issues with these calculators, please contact thier owners. I can't be responsible for thier accuracy.
Automatic calculators - Webpages and Excel spreadsheets
Webpage V2 calculator with metric conversion and Porsche specific tweaks by Croisened -
http://www.croisened.com
Webpage V2 calculator with metric converstions by iammatt00 -
http://fm2calc.ruinedmylife.com - new features coming soon
Webpage V2 calculator by redshirt1701 -
http://www.redshirt1701.com/Forza2/suspensioninput.cfm
Flash V2 calculator with metric conversion by qbix -
http://www.ondaground.net/flash/fm2
(Note: flash file can be downloaded and run locally)
Excel spreadsheet V2 calculator with metric conversion by Shemwhistler -
http://tinyurl.com/3blafu" target="_blank" title="http://tinyurl.com/3blafu">http://tinyurl.com/3blafu
Updated 7-30-07
Excel spreadsheet by kaedo/revan
http://revan.us/feuerdog-Forza2_suspension_tuning-Kaedo.xls
Porsche (P Cars) specific Version based on V2 by Carn
http://www.recoil.co.za/stuff/fm2/pcalc_v1.0.xls
Excel spreadsheet by Aurien -
http://www.hrolt.com/index.php?name=Downloads&file=details&id=7
Updated 7-20-07 |
