Teach me how to tune? Please

Wondering if anyone would want to spend some time to teach me how to tune. Do know some of the very basics, but I would really like to learn the finer points of tuning. I drive competently so I can be very consistent. Not looking for leaderboards times. Just want to learn how to build and tune my own cars. Thank you.

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While browsing facebook i came across these two spreadsheets. These are both a fairly realistic way of tuning the handling platform. Meta builds are usually similar to these but to extremes.

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I have seen those during past forza games. Sometimes I do struggle to know what exactly is happening with the car on the finer side. That’s part of what I’d like help with. Would you be open to one on one teaching in game?

Would anyone seeing this thread be willing to work with me one on one in game to teach me tuning and builds?

Yea, i can certainly help with that. Im no expert by any means but i can usually cut my times by a few seconds from the standard builds forza gives you

There are countless freely available tuning guides that will easily turn up in a quick online search.

Tuning can be quite situational/subjective - there is no one, single, universally “correct” way to always tune all cars.
There is no magic one-size-fits-all formula or app that can take all relevant factors into account since so much can vary by car, by track, & by driver preference.
Tuning is best done on-track on a car-by-car & track-by-track basis.

You don’t need to be an engineer or a physicist, but a solid foundation for race tuning is built on conceptual awareness of:
• the basic function/role of some vehicle parts (engine, transmission, springs, dampers, anti-roll bars, differential, aero, tires, etc.),
• some simple vehicle dynamics (weight balance, weight transfer, the traction circle, etc.),
• and some core race driving principles (racing lines, braking points, apexes, etc.).

…When you get the gist of those fundamentals, tuning is largely just about connecting cause-&-effect:
• identify what the car is doing (effects like oversteering or understeering) and when (under braking, during corner entry, mid-corner, during corner exit, on straights, etc.),
• connect the behaviors you identified to which adjustable settings affect those behaviors (like front-vs-rear suspension balance),
• and start the process of making some changes to those settings (like softening or stiffening your front and/or rear springs or ARBs), testing your changes on-track to see how they affect the car’s behavior, making further adjustments if necessary, and re-testing iteratively until you get the best result you think you can get.

What’s “optimal” varies from car to car, from track to track, from event-type to event-type, & from driver to driver:
• some cars have characteristics that make them behave differently from other cars (front-wheel-drive versus rear-wheel-drive versus all-wheel-drive, front-engine versus mid-engine versus rear-engine, short wheelbase versus long wheelbase, etc.), thus requiring different setups,
• some tracks can be completed faster with cars that achieve higher top speeds, while other tracks can be completed faster with cars that prioritize better handling/cornering over top speed,
• cars are setup differently depending on whether you’re road/circuit racing, drag racing, or drifting,
• and some drivers are able to run their fastest laps with looser cars, while other drivers put down their fastest laps with more stable cars.

Upgrading/building (parts selection) in Forza has historically been about optimizing the PI (performance index) costs & benefits of each component to get the most competitive overall platform.
There’s often a number of different ways to build/upgrade a car from the parts available, but we usually cannot install everything we want since we’re limited to a max PI threshold in each class, so every choice comes with trade-offs, like:
• installing upgrades for better handling can help you carry more speed through turns, making it easier to overtake opponents who need to slow down more while turning because they have less grip - but the trade-off is that you’ll have less PI available to upgrade your horsepower, making you vulnerable to being overtaken on straights by opponents who have more horsepower;
• installing upgrades for more horsepower can give you quicker acceleration and higher top speed, making it easier for you to overtake slower opponents on straights - but the trade-off is that you’ll have less PI available to upgrade your handling components, forcing you to slow down more for turns since you’ll have less grip for cornering, and that’s where you’ll be vulnerable to being overtaken by opponents who have more cornering grip.
…and the way you tune your car can depend greatly on which trade-offs you make in the build/upgrades/parts.
…and the same build on the same car will likely not have the same level of competitiveness across all tracks - tunes are often purpose-built for certain types of tracks/events.

The core tuning principles usually work similarly across most titles, though each game/sim has its own little quirks where some settings might not behave exactly as expected, and the different physics engines in different titles make it such that the exact same settings would not likely recreate the exact same effects when copied between the same car(s) across different titles.

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I have read and watched multiple tuning guides and although they do help me to an extent, they don’t work with you to identify issues and work with you on how to correct those issues. Back in Forza 5 a guy worked with me and I got really good. Years of not playing, I just forgot most everything!

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I would appreciate that McFlufferten, thank you.

When turning, lateral/centrifugal force & weight transfer push the car sideways, outwards away from the direction you’re trying to turn:
the car leans right when turning left,
& the car leans left when turning right.

Oversteer & understeer can happen when there is a substantial imbalance of more lateral/sideways movement at one end of the car versus the opposite end (front vs. rear):

• oversteer = the rear is pushing out laterally/sideways more than the front, making the car prone to rotating/spinning;

• understeer = the front is pushing out laterally/sideways more than the rear, making the car go straighter/wider towards the outside instead of turning in more sharply.

Adjustable tuning settings can give you some control over how a car reacts to lateral movement, allowing you to change a car’s tendency to oversteer or understeer by:
making the looser/faster end of the car more resistant to lateral movement,
and/or by loosening the slower/sluggish end of the car so it can laterally move more freely.

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Add me. Gt Mcflufferten. Ill try to remember to add you next time im on too. Shoot a message any time im on and we can get some laps in. I have something like 1m credits so we can pick a car and tune it together, that is if we can get the custom multiplayer lobbies to actually work lol.

Edit: realised i could use the xbox app to add you.

ForzaTune Pro! Been using it ever since the lauch of Forza 7 and Horizon 4!
You get the full fine tuning and from there you just have to tweek it to your driving style which you can also do it in the app! After the result given, whatever you’re feeling it’s not ok, go back to the tune in the app and go to customize tune. This last option it’s not avaliable in the free version though…

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I don’t want to use a tuning calculator. I’d rather tune on my own, but thank you for the tip.

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the app turns into a great teaching tool because as you use it and start sliding the adjustments to account for corner entry understeer or corner exit oversteer you start learning what adjustments need to be made. after this you stop relying on the app and start relying on your new found knowledge of what the suspension needs to get through the corner fast and efficient.

it took me about 2 months to gain the confidence to call myself a tuner.

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don’t worry about all these crazy pdf bs pictures lol

go watch this video and i promise you will improve your lap times and tuning skill insanely fast

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also on the adjustments and how to identify problems forza is extremely simple when it comes to tuning and pretty much everything is the same based on drivetrain just minimal changes are made based on driving style and tracks you race on.

the vid i linked is pretty good to get a base tune and keeps everything simple and easy for beginners i had no clue how to tune and simply didn’t understand any video until i seen this one

here is the basic stuff i do for gt cars

  • set psi betwen 26-29, with the rear being a bit lower especially in the mid and rear engined cars
  • adjust aero. usually its maxed out but sometimes its not, usually when the track has a long straight
  • adjust gear ratios on the graph so that its a nice curve with 1st gear being the longest, getting shorter with the gears. I start by setting the last gear to the top speed, then adjust first gear by bringing it in, and adjust the others from there
  • lower camber to -1.3f and -0.7r, increase caster to 7.0. I also like toe front 0.2 and toe rear -0.2 but that’s not necessary
  • increase stiffness of basically everything by a lot so that the car is responsive and rotates well, but usually not close to max so that its still controllable and stable enough. anything with stiffness is pretty much stuff you play around with
  • decrease ride height to the bottom. increase it from there by 1 or 2 notches if the track has high curbs
  • adjust diff. on most cars i set it to 85% accel 15% deccel
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Maybe it’s rose tinted glasses but I remember reading some really good guides back during the FM2-4 era that did a great job explaining the LOGIC and THEORY behind tuning adjustments. I feel like there was better information about reading the telemetry back then too. Again, rose tinted glasses, but I feel like the telemetry system from FM4 was more communicative than FM7 or, from what I’ve seen FM’23.

It’s written more for FM7 so I don’t know what it has about the new settings for RCH, AD, and AS, but this guide by Forza Quick Tune is probably the best written I’ve found so far in the modern era.

The way i set up my cars is so different from you.

  • set psi between 30-32 once warm, with the rear being a bit lower especially in the mid and rear engined cars
  • Set aero as low as possible as to keep speed high on straights and increase by 10% or so if you are scrubbing off too much speed in corners and tyres are chirping
  • adjust gear ratios on the graph so that its a nice curve with 1st gear being the longest, getting shorter with the gears. On RWD cars you should have full traction by gear 2 on A and S cars and by gear 3 on R and P cars
  • camber between -2 and -1 f and r, caster 5.0 to 6.0 as too high of a caster creates too much camber. Run telemetry and make sure camber never goes above 0.0 while cornering but try to get it as close to 0.0 as possible. I also like no toe unless the vehicle is unable to get stable or turn in well without it as it adds drag on the tyres slowing you down and increasing heat causing extra wear and especially with race tyres you dont want them above about 240°f or they begin to significantly lose traction (another reason to keep aero low as it adds heat into the tyres)
    *Arbs: halfway between stock and min on front
    Halfway between stock and max on rear to start for AWD and FWD cars, RWD i start at 9.2f and 27.7r. then i adjust from there to manage over/understeer
  • Decrease stiffness of springs and dampers. I pull up telemetry and see what my compression percentages are on my springs. If say springs are normally 1,000lbs f and 1,000lbs r. And my highest spring compressions were 73% front and 64% rear than i will add 5% for buffer. So id set the springs to 780lbs f and 690lbs r. Then do the same with the dampers. If rebounds were 10f and 10r set to 7.8f and 6.9r. then set bump to 2/3 of those values (5.2f and 4.6r) a softer setup isnt thrown off by bumps as much and can often be a lot smoother (especially on controller)
  • Suspension Geometry- a bit stiffer setting at the front can increase responsiveness. The same goes for the rear – although a higher setting will lead to less grip at the exit. Hence, reducing this in wet weather might be a good choice to aid traction in low grip situations.
    .8 to 1.2 f and r seems to be a good value for this
  • decrease ride height to one click above the bottom. increase it from there by 1 or 2 notches if the track has high curbs
  • adjust diff. on most cars i set it to 40 to 60% accel 20 to 40% decel for rwd cars, 20 to 30a and 0 to 10d for fwd, and rwd values of 20 to 30f accel, 40 to 60r accel, 0 to 10f decel, 20 to 40r decel, and balance of 60 to 70

Then once you have these values set up adjust to fit your driving style and the car.

Test suspension settings
Is it bottoming out?
Test camber settings
Never goes positive?
Test tyre heat

Best grip at 176f for street, 203f for sport, 221f for race
temps as close to equal as possible
No more than about 20°f from inner to outer (about 10 to 15 is best)
Greater than 20, lessen camber
Outside hotter than inner, increase camber
Outside and inside hotter than middle, pressure too low
If middle is hottest, pressure too high

Corner entry understeer:
Adjust tyre pressure ±
Front springs and arbs down
Rear springs and arbs up
Toe out f and r
Front downforce up
Rear downforce down
Diff decel lock down f and r
Front bump up
Front rebound down

If the understeer is only under braking move bias toward rear (a little bit is normal under braking)

Mid corner understeer:
Rear arbs and springs up
Front downforce up
Rear rebound and bump up
Adjust tyre pressure, camber and caster ±

Corner exit understeer:
Centre diff rear bias >
Rear accel lock up
Front accel lock down

Oversteer:
Entry:
Front springs and arbs up
Toe in f and r
Diff accel lock up f and r
Mid:
Front arbs and spring rate up
Front rebound up
Adjust tyre pressure and rear camber ±
Exit:
Centre diff front bias <
Front accel lock up
Rear accel lock down

Transitioning problems? Adjust damping and antirolls
Thrown off by curbs? Adjust bump stiffness
Tyres not warming up? Increase downforce or adjust toe. Cold tyres and understeer, increase toe out. Cold tyres and oversteer, increase toe in
Bouncy and shifting weight too much? Increase bump damping and spring stiffness
Not braking well enough? Lessen front camber and increase caster and move brake balance toward the front wheels a bit stiffen suspension in the front
Low top speed? Reduce aero and adjust final gear

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The key to a base setup, in FM or IRL, is to corner weight the car before ever heading out. Forzatune Basic is a free phone app that easily gives you a base tune based upon total car weight, front/rear weight bias and car class. You’ll need the race suspension, obviously. Tweak from there.

I’ve got a question for the tuners out there, can you eliminate some understeer with the stock tune’s tire pressures?

If so how do you dial that in?