Where do you start?

[darkstriderman]

To tune a race car you have to have a FOUNDATION to work from and a STARTING POINT to start tuning from. A foundation being your chosen (because you CAN ungrade) max power of the car i.e 300bhp and the chosen weight i.e 1230kg and the weight distribution is somewhere near these variables,(60%-40%) (50%-50%) or 40%-60%).
Now you have a foundation that you are not going to change, because you are not going to add/reduce anymore power or add/reduce anymore weight, so this car is now ready to be tuned for a track.
This is now the STARTING POINT. Scaff guide on how to tune is an excellent guide, but i have found guides to be just that, guides, with lots of variables to choose from WHEN you get LOST or you do not KNOW WHERE or WHAT to start Changing to make you car quick/quicker around a chosen track (i.e what variables do i start tuning first on my car, from the default suspension settings).
So lets say i have chosen the oval track to tune my car on and have set a lap time using the default settings. Most guides say you have to tune the suspension first as that is the main thing to get you car in sync with the bumps of the track, but the suspension consist of ride height, spring rate, shocks ext/com and anti roll bars.
So what do i change first from that list, Most guides tell me its not the spring rate as this is a fine adjustment tool as is the anti roll bars so we are left with shocks com/ext and ride height, i think, (please correct me if you know or feel i`m wrong on any bit of this thread) you start with shock compression, as the extension should be set higher (x2 was a rule of thumb from other gt titles) than compression this is a known rule (i think). As the extension has to push and reset the car to it normal position quicker for the next bump, once this is done the car should be quicker and smoother around the track, than the default settings lap i did. I think you should change the ride height to a very low setting, as low as you can go and look out for bottoming out and wheels hitting the wheel wells. Once this is done the car should be quicker around the track. I think the spring rate has a certain range where it can be moved high or low within each shock extension/compression range chosen, (this is their relatsionship) meaning once you set the overall shocks for the track i.e ext/com, if you go too high or too low with the spring rate you will have to re-adjust the shock again.
Remember spring rate and ride height also go hand in hand so if you are going alittle harder with the spring rate within the range of the shocks ext/com you have set, then lower the car accordingly. (look out for bottoming out and wheels touching wheel wells) The anti roll bars should be set last because they only work when the car is moving laterally i.e long sweeping corners or fast and short sweeping corners to giving you under/oversteer.
So in a nutshell, shock compression combine with extension 1st
2nd lower the car as low as the track will allow.
3rd use spring rate to adjust hardness=flat track softness=bumpy track, hard/soft=under/oversteer. Remember, change the spring rates too high or too low and you will have to re-adjust the shocks. 4th re-adjust the ride height to work with the new spring rate. 5th anti roll bars for long/fast and short sweeping corners.

As i said before please let me know if i`m wrong and add your own input

 

[vett'e]

To tune a race car you have to have a FOUNDATION to work from and a STARTING POINT to start tuning from. A foundation being your chosen (because you CAN ungrade) max power of the car i.e 300bhp and the chosen weight i.e 1230kg and the weight distribution is somewhere near these variables,(60%-40%) (50%-50%) or 40%-60%).
Now you have a foundation that you are not going to change, because you are not going to add/reduce anymore power or add/reduce anymore weight, so this car is now ready to be tuned for a track.
This is now the STARTING POINT. Scaff guide on how to tune is an excellent guide, but i have found guides to be just that, guides, with lots of variables to choose from WHEN you get LOST or you do not KNOW WHERE or WHAT to start Changing to make you car quick/quicker around a chosen track (i.e what variables do i start tuning first on my car, from the default suspension settings).
So lets say i have chosen the oval track to tune my car on and have set a lap time using the default settings. Most guides say you have to tune the suspension first as that is the main thing to get you car in sync with the bumps of the track, but the suspension consist of ride height, spring rate, shocks ext/com and anti roll bars.
So what do i change first from that list, Most guides tell me its not the spring rate as this is a fine adjustment tool as is the anti roll bars so we are left with shocks com/ext and ride height, i think, (please correct me if you know or feel i`m wrong on any bit of this thread) you start with shock compression, as the extension should be set higher (x2 was a rule of thumb from other gt titles) than compression this is a known rule (i think). As the extension has to push and reset the car to it normal position quicker for the next bump, once this is done the car should be quicker and smoother around the track, than the default settings lap i did. I think you should change the ride height to a very low setting, as low as you can go and look out for bottoming out and wheels hitting the wheel wells. Once this is done the car should be quicker around the track. I think the spring rate has a certain range where it can be moved high or low within each shock extension/compression range chosen, (this is their relatsionship) meaning once you set the overall shocks for the track i.e ext/com, if you go too high or too low with the spring rate you will have to re-adjust the shock again.
Remember spring rate and ride height also go hand in hand so if you are going alittle harder with the spring rate within the range of the shocks ext/com you have set, then lower the car accordingly. (look out for bottoming out and wheels touching wheel wells) The anti roll bars should be set last because they only work when the car is moving laterally i.e long sweeping corners or fast and short sweeping corners to giving you under/oversteer.
So in a nutshell, shock compression combine with extension 1st
2nd lower the car as low as the track will allow.
3rd use spring rate to adjust hardness=flat track softness=bumpy track, hard/soft=under/oversteer. Remember, change the spring rates too high or too low and you will have to re-adjust the shocks. 4th re-adjust the ride height to work with the new spring rate. 5th anti roll bars for long/fast and short sweeping corners.

As i said before please let me know if i`m wrong and add your own input

Its great to have so many people interested in tuning their cars. Anyway, lets get straight to the point.

I used to have the same line of thought as you, until I was corrected by a certain somebody that LSD settings are crucial. At the end of the day, no matter how good the suspension, it is ultimately the tires that deliver the power to the tarmac, but prior to that, the power must be transmitted and distributed through the differential.

My tuning procedures are as follows;

- LSD setting (initial torque is the most important aspect in my opinion)
- Spring Rate (i'm not sure how accurate PD has made their physics engine, but you can run some calculations by dividing the mass on each wheel by the spring rate. This should be indicative of the static sprung height)
- Dampers (conventional race specifications have higher rebound than bound)
- Anti-roll Bars (I like my car to be taut, so stock ones aren't usually adequate in my opinion)
- Negative Camber (anywhere between 1.6 - 2.6 is acceptable, bare in my the drive train layout, different layouts call for different camber angles)
- Slight front toe-out (just a tad.)
- Brake Balance (front bias unless you drive backwards...)
- Aerodynamics (this can be done at any stage, its best to crank it up to 90% of what the max setting is so you can make adjustments when needed)

* LSD - if a car over steers on acceleration violently, but there's a natural tendency to actually under steer - then lower acceleration sensitivity
* Anti-roll bars should be set in conjunction with camber. If a car requires too much camber, then thats indicative that there's too much roll!
* Don't use too much toe-out at the front, it makes a significant difference during mid-corner.
* Ride Height should be adjusted separately for each track. Smoother tracks can run lower ride heights and vice versa
* more testing and evaluation, tune and then tune some more then test again.

I apologize for being so brief, but I think I've posted replies about tuning procedures at least twice now.


BTW. there's a ferrari tune available on Avid.

Thanks

 

[nomis3613]

Hi. Everyone has different tuning preferences (even to achieve a similar result) so people have very different "procedures" for tuning to go with this. I think the most important thing is actually recognising when to ignore your procedure! Because sometimes a setting is so wrong that it needs to be fixed before you can start to fine tune the other settings.

FWIW here is my "procedure" for GT4 (I haven't started tuning in GT5 yet): https://www.gtplanet.net/forum/showthread.php?t=127310#post4045410

Personally I don't believe the "rebound is 2-4x bound" text seen in the tuning screens. Sometimes it turns out that way, but bound and rebound do different things so often the best result for a car doesn't follow this rule of thumb.

Hope this helps.

Simon

 

[darkstriderman]

I think tyre type is the most crucial point, as they are the first point of contact between road and suspension. Things like camber, toe and lsd are for fine tuning your car when you have a good foundation/suspension, i have come across tuners that have said lsd does not make a big difference to their car, but i think it just depends on the car power, if the car is a monsters in bhp (causing traction problems) then you will see the beneifits of lsd more. A good example would be the speed 12.

 

[darkstriderman]

NOMIS3613, i disagree with you my brother. i think there is order that you have to go thru first with suspension, why does the default suspension spring rate setting front and rear relate to each other giving you good medium/soft spring rates but then you get unbalance (equal) shocks, (stiff) high anti roll bar settings and 0.20+ toe on the rear. Tuning is ment to take time to get it how you like or close to how you like. Check scaffs HOW TO TUNE GUIDE, know your car layout (tyre type being used)bahbahbah, is the track smooth or bumpy bahbah. Now, i tune my car with no or added power or weight reduction for my foundation, the only upgrades i use for my foundation is full transmission, full suspension, LSD and whatever tyres. Once i have a smooth ride and quick consistent lap times with my foundation settings, then i start upgrading power and weight reduction so when i do upgrade on power or weight reduction i have an idea of what i have to re-tune, i.e the extra 10% power that the racing exhaust gives you means your car now has an extra 10% power which means 10% more weight transfer (pitch and roll)( 10% over all 4 tyres) now i have to retune the suspension which will affect other settings just alittle and maybe the LSD, but because it is only a small change in power and weight transfer to handle the extra 10% of power over the 4 tyres, it will be small tweaks and here and there no big changes unless you upgrade in bulk (buy every upgrade all at once) and the same for weight reduction all though i recommend you weight reduce first before you add power (my choice would be in car layout/foundation stage so you know the weight is not going to change ever again) and this is the way a car i think should be tuned. Here is a lap time and my car layout, this is how me and my guys race to make it like a track day event, stock cars with ajustable suspension, transmission and lsd with racing tyres. my set up stock ferrari 458 italia highspeed ring, full suspension, full transmisson, lsd and soft racing tyres, if you beat my time with your own tune version i will gladly say i got it wrong. Time 1.03.724 (plus i have zero camber and toe, i got the suspension doing the work)