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Terrell Olvera
05-11-2017, 05:57
Just looking for tips that people use to fine tune the 3rd springs. Since these limit vertical movement, I would imagine they would be highly useful for the high downforce cars that have them. Do they end up being the main springs that you adjust for performance?

Since we don't have a good way of logging ride height, what are some good methods to fine tune the 3rd springs? Do you damp them at all? Any basic guidelines you can recommend (i.e. use more/less of a difference between regular front/rear springs and make front/rear balance adjustments through the front/rear 3rd springs)?

Racefancy
05-11-2017, 11:03
Yep, you're correct that they're generally used for high downforce cars to control the platform in an attempt to reduce compromises with lateral springs to both control the platform and transient behaviour. Usually you adjust them to control the rake of the car for straight line performance (which includes braking and accelerating) but they shouldn't be tuned to control the behaviour of the car in corners and you shouldn't view them as a device to control the balance of the car (although they can if you're too aggressive with their settings).

Personally I don't like running springs on the 3rd elements if the option is available because it means they're then always active and will impact cornering behaviour to a degree, it's an added variable which doesn't need to exist as you have lateral spings/damprs and roll bars to control that. I prefer to use them to control the rake of the car with bump rubbers and gaps to ensure they're only used as a rake & ride height adjustment tool.

Within the game I look at the telemetry screen travel section which shows you how the rake of the car changes depending on speed and with that I basically adjust the 3rd elements so that down the long straights the rear squats enough so the car is running relatively flat (same ride height front to rear) which reduces drag.

If your setup uses soft front springs and stiff rear springs you might find the car has a nose down attitude down the straights which is undesirable, so for example you might set the front 3rd element to have a small amount of compression before the bump rubber stops vertical movement and a larger gap at the rear to allow the rear to drop more, so you can control how the car pitches etc using these. There's always compromises though, I find that if under heavy braking you're heavily into the front 3rd element bump rubbers that you lose some braking performance but that's up to individual testing.

Wayne Kerr
05-11-2017, 14:07
they're then always active and will impact cornering behaviour to a degree,.

please elaborate on how you come about this conclusion.

Racefancy
05-11-2017, 14:20
please elaborate on how you come about this conclusion.
Assuming the spring is loaded at static ride height, any motion which activates both lateral springs into heave will also be activating the 3rd spring, so now your ride frequencies include not only both lateral springs but the 3rd spring as well, effectively adding additional stiffness to that end of the car. If for example we're talking about the rear 3rd spring, it means that as soon as throttle is applied exiting a corner, the rear 3rd spring will be adding additional stiffness to the system, so it has to be tuned with transient conditions in mind as well as the lateral springs/dampers & roll bars. To me it adds an unnecessary variable which doesn't need to be there. I've seen top level LMP cars run with and without springs in their 3rd elemenets, so like everything in racing there are differing opinions and philosophies, so always interested to hear reasons to the contrary.

Terrell Olvera
05-11-2017, 15:03
When you say gaps, are you talking about ride height adjustment or bump rubber length?

Wayne Kerr
05-11-2017, 15:39
Assuming the spring is loaded at static ride height, any motion which activates both lateral springs into heave will also be activating the 3rd spring, so now your ride frequencies include not only both lateral springs but the 3rd spring as well, effectively adding additional stiffness to that end of the car. If for example we're talking about the rear 3rd spring, it means that as soon as throttle is applied exiting a corner, the rear 3rd spring will be adding additional stiffness to the system, so it has to be tuned with transient conditions in mind as well as the lateral springs/dampers & roll bars. To me it adds an unnecessary variable which doesn't need to be there. I've seen top level LMP cars run with and without springs in their 3rd elemenets, so like everything in racing there are differing opinions and philosophies, so always interested to hear reasons to the contrary.

this is off the ligier p3 manual that I'm staring at in the face right now. I mean unless I'm missing something (and considering i still have a job with the guys who ran this car for the entire 17 season, maybe it isn't me who's missing something)

how is that third spring going to activate when in anything but pitch / heave.

https://i.imgur.com/8zm5J3V.jpg

second of all, I don't think i've ever seen a driver worth his salt who goes on the throttle only when the car is dead straight.

if the ARB is activated, the third spring isn't. That's the whole point of whomever invented the third element, is (as you said) perform platform control in a straight line so the corner springs deal with the cornering.


When you say gaps, are you talking about ride height adjustment or bump rubber length?

the popular jargon is packer gaps. if fancy is thinking the same thing i'm thinking.

Racefancy
05-11-2017, 23:29
this is off the ligier p3 manual that I'm staring at in the face right now. I mean unless I'm missing something (and considering i still have a job with the guys who ran this car for the entire 17 season, maybe it isn't me who's missing something)

how is that third spring going to activate when in anything but pitch / heave.

https://i.imgur.com/8zm5J3V.jpg

second of all, I don't think i've ever seen a driver worth his salt who goes on the throttle only when the car is dead straight.

if the ARB is activated, the third spring isn't. That's the whole point of whomever invented the third element, is (as you said) perform platform control in a straight line so the corner springs deal with the cornering.



the popular jargon is packer gaps. if fancy is thinking the same thing i'm thinking.
With the ARB activated the rear suspension is still able to compress and any time the rear dampers are both in compression, even if one is compressed less than the other in roll, the 3rd element will also be compressed by some amount, so any acceleration while there is still roll in the car (warp) will activate it unless you have a car which holds a wheel in droop under acceleration, which wouldn't be very handy.

Maybe an easier way to explain it is a high speed corner with high aero loading on the car. As you turn the high speed corner, the ARB is obviously active and the 3rd spring which was heavily compressed from the downforce isn't going to suddenly reset itself to zero when the corner is turned, it will still be heavily compressed as the car takes the turn, basically any time the car is in a warp mode.


When you say gaps, are you talking about ride height adjustment or bump rubber length?

Sorry mate, what I mean is the "air" gap to be compressed before the packers/rubbers are activated. I think in this game when it says bump rubber length, the longer that length, the smaller the "packer gap".

hkraft300
06-11-2017, 11:46
Subscribed.

I'm curious to hear people's thoughts on the 3rd spring.
Got any reading material?

I've yet to experiment with it.

Terrell Olvera
06-11-2017, 16:04
I took the Formula X to Silverstone and was bottoming out at high speed. I maxed out the 3rd springs and was still bottoming out (default ride height). I then maxed out the regular springs and was still bottoming out. I then put the springs back to default and set the 3rd springs to zero. Still bottoming out but the car felt better in the turns. I then raised the ride heigh on both ends and the bump stops on the rear (to be level on the straights) and set my fastest times.

I learned a lot from this test and find it funny that removing the 3rd springs was the solution in the end. So far, at least. As I learn and experiment more I will try more setups with various 3rd spring options.

hkraft300
07-11-2017, 04:01
Well your problem initially was that your ride height was way too low.
Can't blame that on ineffective 3rd spring tuning, can you?