Is this theory for springs the best? How do I set dampers?

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Hi all,

I’m in no way a professional tuner. In fact I’d say I’m average at best but I do try and do see progress in my tunings so… DON’T JUDGE ME! [jokes] LOL

Anyways, I have watched TONS of how to videos and picked up some tips and tricks from there as well as on discussion boards and what-have-you.

My question is about springs. I saw on YouTube [sorry to the guy who did it I’m horrible at remembering names.] and he did this formula and it seemed to work pretty good.

Weight of car x front % divided by 64 x 31.193 - that gives you front spring

for the rear you do the same only take the remaining % off the front [so if front% was 51, for rear you would do .49]

Like I said, in no way am I an expert but I find the springs to be to stiff compared to if I use the Forza 6 tune app. [ Of course there is tinkering of the springs in both cases]

Heres an example [this is my 69 Nova]

The math formula way…

Front Springs

Weight: 2958 x .54 [front %} divided by 64 x 31.193= 778.5 [rounded off]

Rear

Weight: 2958 x .46 [100- 54=46] divided by 64 x 31.193= 663.2 [rounded off]

Forza App

The app asks what tire sizes your using, the aero is set at, weight and front %. The tires I have are front- 265/55/14 Back- 345/40/14 and the aero in this car is set to full F- 100 R-200 [just in case some of you were trying to figure out just how far off my tune is LOL] Also the oversteer/understeer is at half as is stiffness on the app. I don’t touch those options ever.]

This is what the app says…

Front- 657.3

Rear- 460.5

As you can see there is quite the difference in the rear setting. My question is which one is the best way to go? I usually do the math then adjust accordingly. So my Nova I have at F- 665.4 and R- 492.2 and it runs pretty well in corners.

Any help would be appreciated. I also desperately need help setting damper. I right now go 10. 5 Front rebound, 9.5 rear and do 5.2 bump front and 4.7 rear cause I read that is a good all around set-up for that [you do between 9.5-10.5 on front and rear rebound. Then you can do 50-75% of that for bump…] I know everyone has an opinion but any tips would be appreciated. No negative comments needed please. Like I have stated many times, I am no pro by any means but love tuning my own cars.

Thanks.

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Maths can only go so far, it depends on the car and what you’re trying to do with it.

For some of the X class cars that aren’t the easiest to drive (Lotus E23, McLaren MP4/4, etc.) I use spring rates that maths probably couldn’t give me, even with downforce considered. At the end of it, the driver has to drive it and has to play by ear as much as the supercomputers do their number crunching.

So, you run what seems to be comfortable and work off that.

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Must remember that using an App, or a given formula to tune a car isn’t what I/many would call tuning…
That’s more following/copying more than anything. The best form of practice is to test, test and test also read, read and read, except the information T10 gives you, like wow - some of that is so off!
anyway…

Springs control transitional weight, the best way to tune this is by going around a tight bend. Then initial ON throttle balance is where you can tune your springs. How soft/stiff you make these springs all depends upon you. The softer the overall springs the more grip you will have out of slow corners, but you’ll find that on high-speed corners this can be drastically different, the car can become unstable. Thus what track you are tuning on, and what track(s) you want it for will determine how you set up your springs and other important settings.

RR

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Thanks for the input guys. I am now putting the spring settings in the middle and going from there as it seems both ways are off for me. I did a tune my way and it seemed to work just as good as crunching numbers. So thanks again for the advice!

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Springs are a black art.

The stiffness controls how much or little of the weight of the car you transfer to wheels. Transferring weight to wheels that need it is good eg lots of weight to the front whilst turning in but too much weight will overload the maximum grip of that tyre. balancing act.

Damping controls how quickly or slowly your car transfers weight to the tyres and how quickly or slowly the weight come of these tyres.

It’s all a balancing act tailored to you and how you drive. A calculator does not know this only you.

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Just to clarify, do the springs and dampers only control the weight transfer from front to back of the car or do they also control the transfer from side to side?

If it’s the latter how can you tune for this in Forza where you can only adjust the settings for the front and back of the car? Or is this what the sway bars are for?

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Next time you’re on, go do a test. Take one of your favourite cars, (make sure your current tune is saved) and set your springs for front and back at the half way point on the slider. leave your bump and rebound at their current settings if you like them. Now whack both arb’s up full and see what the car does under straight line braking, turn in, acceleration and coasting through corners. Then drop the front to half way and do the same, note the differences. Drop the back to half way, repeat, and repeat for both sides at the softest setting. Make note of what the car does. Find a turning setting that you like with your new knowledge and leave the settings alone.

Now go to your springs, do the same test with the roll bar settings left alone, make note of the character changes of the car doing the same test while changing the spring rates. Doing this will help you find the correct suspension balance for the car.

I’m still learning about bump and rebound, but I tend to have the rear rebound as the highest setting to encourage the cars weight to the front wheels, I set the front bump and rebound to about 75% of this to keep the front wheels stuck to the Tarmac, and the rear bump can just sit at a number close to the front settings because I don’t know what it affects. Someone will likely tell me I’m an idiot, but, the point of this reply is to tell you to try the extreme settings so that you know what the changes make to the car. This way the calculater can be thrown out the window and you can set the car up to suit you.

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Don’t forget the ARB! Springs+ARB+Dampers all work as a system.

For a 3000 lb car, I consider 700 lb/in excessively stiff. It’s still drivable, but stiff springs make ARB+Dampers obsolete as stiff springs will override them. I’d use about 300~500 in/lb range.

As mentioned in previous responses, soft suspension gives slightly better grip but at the expense of agility. Stiff suspension increases the car’s agility/stability but at the expense of slightly worse grip. At low speed, soft suspension is beneficial but at high speeds, stability may serve better.

Use springs to support the car’s weight around the track in general but especially for braking+acceleration. This usually results in softer spring rates.

Use ARB to stiffen the car’s suspension for corner handling & balance. This tightens up the car in corners.

Then use Dampers to control the car’s bounce during braking/acceleration/cornering. If you’ve damaged the car’s suspension in a race, you know what it feels like to lose dampers = bouncing on a pogo stick.

Then you can add aero to further improve the handling.

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I use an equation that is a little simpler.

Overall Weight X % of distribution (divided by 2) =

However! I find that the game tends to be a little stiffer so I always subtract 100lbs of the result. It always gives me a solid base to work from. From there I typically end up adding a little rear spring to loosen up. So example:

Car Weighs: 2500lbs
Distributed: 52%

2500 x .52 = 1300lbs (divided by 2)= 650
Front: 650
(Again for Rear)
2500 x .48 = 1200 (divided by 2) = 600
Rear 600

Again I always drop 100lbs from the result so I would set this at 550 front 500 rear and work up to stiffen.

Edited…sorry I’m a dumb ass. Divide by 2 not 4

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May i ask why divided by 4? I mean, there’s only 2 wheels at the front… just an observation.

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Edit…I’m an idiot. Yes by 2 not 4

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225lbs front spring rate for a 2500lbs car is definitely too low. Double that number and you are in the right ballpark.

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My base tune is the default settings, if i start using formulas and/or apps I’ll probably go crazy…lol…
Best thing one can do is to test, test, test and more test, let the car tell you what it needs with a good understanding of what you are changing and why. As we all know tunes are highly personal to suit your driving skills and dictated by the track.

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Dampers control the rate which your springs compress and decompress. With respect to the previous responses, you tweak the dampers to affect the rate at which weight transfers during maneuvers. This primarily impacts the handling balance of the car, whether it oversteers or understeers when given certain inputs.

I tune my springs primarily to prevent my suspension from bottoming out. Their primary function is to keep the tires off of the fenders. Your approach is sound in that it equally splits the burden between the front and rear axles, and if you find that it produces a car that handles how you like, stick with it. But use the game’s telemetry tools to fine tune it. You might find that your settings are too stiff, causing the car to lose traction and skittered over bumps mid corner or in braking zones; or too soft, causing you to bottom out and completely lose traction at inopportune moments.

Also pay close attention to ride height. I haven’t quite determined how the game handles suspension travel in relation to the suspension’s bumpstops, but on a real car the lower you go the closer you are to bottoming out and sending the spring rate to infinite, causing sudden loss of traction. The way you deal with this is by using a stiffer spring. For my street cars I tend to prefer the softest spring my tire will handle while keeping the top mounts away from the stops.

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Yes this! I had a long rant but deleted. In a nutshell the spring rate increases with travel. So a 600lbs spring requires almost double the force to compress any further after just an inch or two in travel. At least that is how it works in the real world. I prefer a softer spring to transfer the weight and a stiffer rebound to create opposing force grip.
I am also a proponent of using the telemetry. I dial in everything from there. I will say I have a nasty habit of building cars that push out mid corner. When I get one of those is when I start to stiffen the rear and weight jack the car to the front