"The Oval Tunery: Tuning Guide"
TUNING OBSERVATIONS
First of all I would like to say that these are my observations on tuning that I have experienced with various cars ranging from street cars, muscle cars, LeMans Prototypes, Formula Cars, Tour Cars, SuperGT & NASCAR's in GT5. These observations are solely my view of the characteristics tuning has on cars in GT5. My view is also obsurced generally towards the theme of my tuning garage "The Oval Tunery".
My observations are clearly based on fast, full throttle race cars prepped for endurance races. Typically RWD (some MR and mostly FR). Also with the new tire model racing hard tires seem to be the way to go now for longer races. In My Opinion the Tire Model needs to correct the top speed thats obtainable by Sports Tires. As in real life the side walls of the tires would blow-out under the extreme forces the undergo at over 200mph. Known by a test I done on Sports Softs at Daytona in a NASCAR full hp against others on Racing Tires. Just too unbelievable.
Like I said these are my observations, no stead-fast rules. And rules are made to be broken. I am just trying to come from a conventional stand point.
Also I would like to say for more detailed information and great reads to expand your knowledge check out this thread: https://www.gtplanet.net/forum/showthread.php?p=5315655#post5315655
BRAKES / LSD / TRANSMISSION
Brake Balance & Braking Sensitivity (via LSD)
Brake Balance is typically user biased. But a balance is required between the brakes and watching the tire wear indicator glow red is an indication that your balance is too high either all around or in the front or back wheels. Also it could be an indication of lock if the car pushes forward too much. Raising Front Ride Height also helps with even weight and load transfer under braking. Lower values in brake balance and brake sensitivity are needed for slower, more technical courses. And higher values in both setting are needed at Faster tracks with hard braking into chicanes, bus stops and hairpins. Advantage of Low values are less lock and more handling capability in corners. The advantages of higher values are responsive brakes, more stability but with the downside of less turning capabilities in the corners. Lock also becomes an issue when using higher values.
Heavier cars require higher values in brake balance and braking sensitivity in lsd, light cars are opposite.
Weight Distribution influences brake balance. Higher downforce also decreases braking zones.
Wheel Spin can be controlled with lower Final Gear settings and lower Initial Torque and Acceleration Sensivity settings. Final Gear and Initial Torque affect wheel spin the most. Higher rear downforce also decreases wheel spin. I typically use lower settings in endurance racing to save tires and the opposite for sprint races. But I tweak this with respect to the tune and handling characteristics as well.
Cornering is broken down into three variables: turn-in, apex and turn-out(exit)
Turn-in can be controlled with toe angles. Apex requires a good entrance and throttle control. Acceleration Sensitivity (via LSD) can control understeer and oversteer in these conditions. Higher values will give more outside wheel spin or understeer (better stability) and lower values will give more inside wheel spin or oversteer (better handling). Both have advantages and disadvantages. And are driver biased as well. High downforce also gives better handling, stability and speed under cornering.
Motor City Tunes actually has a really good explaination of how the LSD works here:
https://www.gtplanet.net/forum/showthread.php?p=4641242#post4641242
Transmissions vary track to track. There are many ways of tuning them.
Closed Ratio Transmissions have same Top Speed as Standard, but better acceleration.
Custom Transmissions are great for High Top Speeds and setting lower Final Gears for less tire spin.
Higher Final Gear for Acceleration, can adjust with lsd to set your wheel spin.
Setting custom transmissions is an art that is car, track and driver dependent. Also depends on the type of race. There are many styles to setting a transmission.
Some drivers prefer 2 to 3 gears whether they are drag racing or circuit racing. Most driver prefer all gears and setting the autoslider 10 to 20mph higher than they redline at the end of the longest straightaway at a particular track. Setting the values higher takes in the account for drag coefficient. At some tracks where drafting plays a big role you will need to set your transmission higher to take in account for higher obtainable speeds while undergoing slipstream. Slipstream is relavent at higher speeds, typically above 125mph and ridiculous after 200mph.
I won't divulge anymore into transmission tuning as there is many ways to set tall or long gears and whether you choose to use all gears or not. For quick tuning I set the autoslider 20-30mph higher than needed. Then I choose a long 5th or 4th gear (my last gear in the gear box) and a tall 2nd gear (track dependent and based on my wheel spin). Then I adjust my final gear to the left for draft tracks or to the right for technical tracks or road courses. I also adjust lower Final Gear for endurance racing and higher Final Gear for sprint races. And extremely high for drag racing. Or extemely low for some muscle cars. And then I fine tune Final Gear for desired wheel spin on turn-exit.
SUSPENSION
Stock Suspension is too soft,need too stiffen the springs and dampers.
Stock Anti-Roll Bars are too soft, need to stiffen.
Soft=Low Values
Hard/Stiff=Hi Values
Loose= Is a term used loosely, stiff cars get too loose. A soft tune will get loose, Etc..
Ride Height is probably the hardest to define. Ride Height balances weight distribution and grip. It also determines Center of Gravity. A lower center of gravity is prefered for stability and handling. Low Ride Height is aerodynamic thus giving more grip and downforce which in return produces drag. All which is ideal in corners. Typically a low ride height gives max grip but may be a bad choice due to bottoming out. Also higher, constant top speed cars will require higher ride heights to produce less drag and more lift. Use that to your advantage or disadvantage. Some people like a lower front ride height so the front tires grip hard into a turn, others like front ride height higher so they feel less understeer entering a turn. Overall ride height is driver preference along with avoiding bottoming-out. Use the Tire Load Indicator to view if your car is bottoming-out.
Spring Rates are more straight forward. Softer springs give the suspension more travel and stiffer springs give the suspension a more rigid feel since it allows for less travel. Therefore typically lighter cars, street cars, and cars with sports tires favor softer springs. Softer springs also provide more grip, better handling and greater acceleration. So the opposite can be said for stiffer springs. Heavier cars, race cars and racing tires favor stiffer springs. Stiffer springs also provide less grip, more stability and a greater top speed.
Sports Hard Tires require softer springs, dampers and anti-roll bars than compared to racing tires.
Racing Tires require stiffer springs, dampers and anti-roll bars than sports tires.
Therefore comfort tires would require softer settings.
Weight Distribution can be used to set spring rates and ride height. Weight Distribution defines handling, acceleration and traction characteristics of a vehicle. An even 50%F/50%R is preferred because it is easy to predict and adjust. It is commonly considered better.
Weight in general measured in kg or lb defines acceleration and braking distance. Lower weight is preferred and provides faster acceleration with shorter braking distance. Also a low power to weight ratio is ideal as this increases acceleration too.
Light Front Ends are faster with softer settings but can be known to be spun by an oversteering rear.
Stiffer springs may need to be in place in front end for cars with these tendencies to compensate for weight distrubtion during turn.
(RWD - typically FR)
Typical Suspension setup: soft front / stiff rear
Combat Oversteer: Stiff front / stiff rear
Combat understeer: soft front / soft rear
Fast straightline: stiff front / soft rear
Fast circuit: soft front / soft rear
Tuning for Daytona and Indy is give or take, typically you combine these two elements until you find a happy median you are fast and comfortable with.
Daytona: Combat Oversteer: Stiff front / stiff rear VS. Fast straightline: stiff front / soft rear
Therefore at Daytona you typically need a Stiff Front and a well settled rear (between soft and stiff)
Indy: Combat understeer: soft front / soft rear VS. Fast straightline: stiff front / soft rear
Therefore at Indy you typically need a well settled front (between soft and stiff) and a soft rear.
But you also have to take into consideration stiffer is better for top speed and stiffer is better for a flat track (not bumpy like Le Sarthe). So you may take this advice and go a little stiffer than suggested. Which is the right way to go for better tire wear.
DIFFERENT DRIVETRAINS
Typical Suspension setup on FR(RWD): soft front / stiff rear
-this typically helps initial turn-in and combats oversteer on turn-exit
Typical Suspension setup on MR (and I'll assume RR too - RWD): stiff front / soft rear with lower settings on brakes
-this typically helps the snap oversteer under braking and combats understeer by loosening up the rear
Typical Suspension setup on FF(FWD): soft front / soft rear and typically higher lsd settings
-this typically tunes out oversteer from front tires and makes the wheels spin adding grip through torque
Typical Suspension setup on 4WD(M4, F4, R4 - based on RWD with a little FWD bonus): soft front / stiff rear with more torque displaced at rear (approx. 70%) and higher lsd setting in front
-this typically tunes out understeer initiated through the heavy weight and gives the front wheels more grip throughout a turn and especially at turn-in
Use weight balance to determine settings in suspension.
In tuning menu, under Body/Chassis look at Ballast. And in this menu it shows you static weight balance of your car. Use these percentages top figure out your car's static values for Springs & Ride Height.
i.e. - Example How To Tune Spring Rates
Just use this example to give yourself an idea of how to fine tune your springs before you hit the track and start tweaking the little numbers.
Weight Balance 55%F/45%R (data collected from ballast setting)
Spring Rate Slider in Front has Range 11.1 to 20. Range is 8.9 @ 55% weight.
Spring Rate Slider in Rear has Range 10.0 to 20. Range is 10.0 @ 45% weight.
8.9 x .55 = 4.895 = 4.9 ....... 11.1 + 4.9 = 16.0 Front Spring Rate
10.0 x .45 = 4.500 = 4.5 ...... 10.0 + 4.5 = 14.5 Rear Spring Rate
This is a good base number for static load (not moving/slow speed). Lots of people like a stiffer Rear for better wheel spin in corners. So some others may even go with 16.5 Rear Spring then thus conforming to the typical softer front and stiffer rear format (which is ideal in theory and does work).
Trick - Tune to Load Balance under hard braking and acceleration......90%F (higher for high load transfer to front under braking) / 60%R (higher for load transfer to rear under acceleration). The 90% Front Load is determined from Indy Oval and Trial Mountain at the sharp downhill left turn after the long uphill straightaway in the tunnel.
i.e. - 8.9 x .90 = 8.......11.1 + 8 = 19.1 Front Spring Rate (applied by typical user = 19.0)
i.e. - 8.9 x .60 = 5.3 ...... 11.1 + 5.3 = 16.4 Rear Spring rate (applied by typical user with conforming format = 18.5)
The basis of this trick is tune your car to the hardest/fatsest turn and braking point of that specific track.
General Road Course Tunes are good because they compensate for a cars natural tendendacies, but fine tuning is needed for longer races when suspension needs to adhere to the specific track where it will undergo forces that vary track to track.
Lower Values will give you more grip and higher values will give you more stability.
This will find balanced springs, but will need to compensate with tweaking on track to wether you will need to stiffen or soften any settings.
Dampers can be tricky. Damper settings dignify compression and decompression(extension) rates. Lower values for decompression and compression exhibit fast rates and higher values give slower rates. Typically you want slower extension than compression or faster compression than extension. This is also driver dependent on small tweaks to these values. Major tweaks are car and track dependent. Typically the rear shocks will be harder than the softer front settings. Extremely fast values would be 1,2 & 3. Soft would be 2 through 6. Hard settings are 5-9. And extremely slow values are 8 to 10. Level Tracks require hard to slow damping. Uphill tracks and downhill tracks usually require opposite types at either end (i.e. fast front, slow rear or slow front and fast rear). Bumpy tracks usually require fast damping. Same for a slower speed track. Fast tracks and banked tracks (High speed ring, daytona Road, Cape Ring, Daytona, Indy) require slow damping.
Anti-Roll Bars helps reduce the roll of a vehicle that is induced by cornering. It connects opposite (left/right) wheels together through short lever arms linked by a torsion spring. A sway bar increases the suspension's roll stiffness—its resistance to roll in turns, independent of its spring rate in the vertical direction. Stiffer Anti-Roll Bars give more oversteer (better corenering) and more tire wear. Softer Anti-Roll Bars (lower values) give more understeer (better stability) and less tire wear. Ideally you want the lowest setting with respect to your prefered cornering style. These settings are car and track dependent. And typically endurance races favor softer values, as oversteer with stiffer bars becomes apparent in later laps when tire preservation is being taken into consideration.
WHEEL ALIGNMENT
Toe Angles and Camber are usually pre-engineered into a car pre-sale to overcome typical forces a car undergoes. Higher values(angles) are required for higher speeds/higher load transfers.
Camber
Need Camber, No 0/0
Adjust camber for maximizing grip at apex in turns. Camber between 1.5 to 2.8 is ideal. Lower settings give more understeer and higher settings give less stability and tire wear becomes more apparent. Higher Camber is needed at High Banked Courses to deal with the offset of Load Transfer under cornering.
Typical Camber Settings for Road Course: 1.5/2.0 or 2.0/2.5 or 2.5/2.8
Typical Camber Settings for Ovals and High Banked Courses: 2.5/2.8 to 3.3/3.5
Toe Angle
Toe Angle adjustments are driver preference mostly and is based on turn-in and turn-out. Front Toe dictates turn-in and Rear Toe effects turn-out but those both cross-reference each other as well. Toe Angles effect Tire Wear more apparent than most other settings. Ideally No Toe Angle(0.00/0.00) is perferred but not always acheived.
Adjust negative toe angle for better turn in (looser)
Adjust positive toe angle for better stability through turns and exiting turns (tighter)
AERODYNAMICS / SLIPSTREAM / DRAFTING
Aerodynamics give less understeer. Front aero promotes oversteer.
Minimul aero values in rear (for a full aero value, say low, around 20) gives you more oversteer with the disadvantage of the rear tires getting loose in the corners which becomes a problem in later laps.
But a hi aero package (say full value 90) gives you more understeer which balances out the over handling over a long course of a race.
Downforce can also be generated by lower ride heights and softer spring rates. A low ride height also has an improved COG (Center of Gravity). A low COG has benefits of shorter braking distances due to less load and weight transfer and less roll in corners. Thus improving grip and reducing top speed as well caused by drag. The opposite can be obtained through lift. Lift can be acheived by high front ride height and higher spring rates. Lift allows for higher speeds and reduced drag. The angle of your front end dictates your drag coefficient which is calculated by your frontal surface deflection. This coeffiecient can tell you if you have too much drag or too much lift. In GT5 there is little to do about fine adjusting this other than trial and error, running tests and taking notes. Experimentation is the best way to fine tune an aero package.
Aero saves tires and gas! Using high aero and running consistant ridiculously fast lap times kills tires. Use aero to balance your driving style with keeping the downforce to your advantage. But not to overkill every turn because of all the grip thats available. This sometimes lead to the misconception that max aero kills tires. Aero used properly preserves tires. Drivers kill tires. Same thing with gas, people believe the wind resistance requires more gas when its the opposite. Downforce generates physics that offset your engines power to maintain your required speed. Thus lowering your rev's. Lower rev's saves gas. Fuel economy is measured in mpg and it's variables are economics and range.
Example - without downforce you need all 500hp to push through the air. But with max force the aero package pushes the air and only requires 450hp to push through the remaining air. This is advantageous most at a long technical track such as Le Sarthe or Monza where tire wear and speed are needed to balance a well setup car for many miles, especially in an endurance race.
High downforce is prefered for cornering at technical tracks and road courses. G-Force which is measured in ft/s^2 or better known as "
g " defines acceleration. It measures cornering, braking and forward acceleration. Higher g's are faster thus better. And are obtainable through high downforce in turns.
Low downforce is prefered at high speed courses where drag becomes more relevant. Some tracks with high speed but with sweeping high speed turns require a balance of aero and speed.
Commonly drivers use high downforce as it is advantageous. Higher front downforce and lower rear downforce is ideal. The exact opposite can be said for certain tracks. Typically smaller technical tracks require higher downforce. But slower speed tracks have disadvantages at high downforce and are more opportunistic with more hp. Aerodynamics have a huge factor above 125mph but effects are noticeable above 60mph. Judgement can be made by cornering speed and user preference on desired handling. Mid values are commonly used as a quick tune and are is not a bad option. No aero is most desirable at Full throttle tracks. But a balance is required at those high speed tracks with non-high banked turns.
The black art of tuning downforce comes into play at Le Sarthe, High Speed Ring, Cape Ring, Indy Road, Indy Oval, Daytona Road and Monza. I usually use low downforce at these tracks, no aero at Daytona Oval. I tend to use more aero for endurance racing and less for sprint racing. But this is also taken into consideration depending on the track, top speed and comparsion to lap times versus strategy (pitting for tires and fuel).
Slipstream is the pocket of low pressure air formed behind the end of a fast moving vehicle. Or defined by wiki as a region behind a moving object in which a wake of fluid (typically air or water) is moving at velocities comparable to the moving object. The pocket of low pressure air creates a vacuum, this is called the wake. The term "slipstreaming" describes an object traveling inside the slipstream of another object. If an object is inside the slipstream behind another object, moving at the same speed, the rear object will require less power to maintain its speed than if it were moving independently. In addition, the leading object will be able to move faster than it could independently because the rear object reduces the effect of the low-pressure region on the leading object.
Drafting effects are obtainable through slipstream at higher speeds, typically above 125mph and ridiculous over 200mph. Slipstream does however exist above 60mph but is far less noticeable. Drag (air resistance) and lift are two variables that are taken into consideration when tuning aerodynamics. And can get very in-depth into physics. But luckily GT5's physics model is dumbed down a bit for us gamers! The only thing to note is drag forces depend on velocity.
Slipstream is divided into upper streamline and lower streamline. Upper streamline has lasting effects over a long distance and at a higher speed. Lower streamline effects only last over a shorter distance and at a lower speed.
As the Upper streamline collides with the car's front end it creates a frontal deflection over the hood and roof, it continues to streamline the sillohuette of the car to the rear end where it pushes back down on the rear tires creating drag. If an airfoil (wing) is in place on the rear of the car and is engineered to give high downforce the streamline becomes turbulent thus producing "dirty air".
Lower downforce combined with the weight of the car and the car's physical aerodynamics define the lift the car creates. Variables taken into calculation are forward thrust, weight of the vehicle gravitating downward, drag produced and lift generated.
Upper streamline air also moves downward at a faster rate than lower streamline allowing for typical dynamics of a vehicle to compress air appropriately around the moving vehicle. Over all when a car enters the upper streamline the current has upward deflection and as the car passes through the streamline gravitates over the car with downward deflection.
Drafting is the act of the following car taking advantage of the positive effects of a slipstream from a lead car. See the definition of slipstream for more detail. This section is going to focus on pack drafts and tandem drafting. Lead car pushes clean air and creates a slipstream for the following car. The following car gets its front bumper onto the back of the lead car's bumper and they drive in tandem. The connection between the two cars reduces drag.
The lead car has less drag on the rear wheels thus allowing it to go faster. And the following car (the pusher) has less drag on the front tires. The contact with the two cars combined with less drag allows these two cars to travel faster. Also the air pocket between the two cars pushes the lead car with its high air pressure athus making the two cars travel faster too. Typically the power gained by a drafting partner is approximately 10hp more than driving solo.
(Example) Approximate top speeds (with no downforce) driving solo 180mph, in a draft (no pushing - just allowing the air pressure to gain more momentum) 185mph, 2 man tandem (bump drafting - two cars connected) 190mph.
Dirty Air is turbulent air, created by the lead car. Dirty air becomes more turbulent with higher downforce settings. Dirty Air has no effect on straightaways. Dirty Air effects cornering. It has bad effects in cornering such as slipstreaming and cars become too loose. The higher downforce packages create less drag which in return can make bump drafting in the corners unpredictable as the lead car has a loose rear due to no drag and the following car has a loose front due to no drag.
Bump drafting with full downforce does in return create less drag overall compared to low downforce tandems. Catching the slipstream behind a team with full downforce is easier to do than a low downforce team but has a lot more dirty air of the back spoiler in the corners. This car becomes hard to push because the rear wheels are not loose enough.
Low rear downforce settings create less dirty air but takes on more drag on the rear as well. A solo driver may choose to use high downforce up front but low in rear. This will give drag across the car, not centralized over the rear. This car will have great solo top speed but will be hard to push (which is what makes it a good solo team setup). And the offset of aero from front to rear creates a thicker streamline which is harder to catch.
A low downforce setup in front and rear creates less drag in rear and more lift in front. This is idle for max top speed. A team with no downforce are harder to pull into their draft but is the easiest to draft and push in the corners and straightaways. As low downforce cars have way less dirty air. These cars are faster with less drag and lift because of their drag coefficient. This makes for great speed, downside is an extremely loose car. But can be tweaked by stiffening the suspension.
Combining teams with high downforce and low downforce cars at Daytona has no advantages. Worst is a team with high downforce, they will be the slowest. These teams allow for other teams to draft very easily around them and provide chaotic turbulence in the corners (dirty air). A team with low downforce will be the hardest to catch draft in and the easiest to push around with no bad effects of dirty air in the corners.
NOT COMPLETE - Hope to soon include diagrams/images as well.
