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CDubLDD
18-11-2017, 23:34
I found a thread in the PS4 section about suspension, but not sure how many people look in there. I'm trying to figure out how to get my suspension to stop bottoming out. Not on every circuit, but there will be some where I have my springs set to what I am comfortable with but the spring telemetry will occasionally flash red. Do I need to add more bump stop to keep that from happening? Remove bump stop? Any help would be appreciated.

hkraft300
19-11-2017, 00:40
It flashes red, I believe, when the spring travel is getting low.
You want the height to stay high enough not to scrape on the ground. Adding bump stop helps in this case.

On some cars, it already has enough ground clearance but the suspension may flash red. This means the springs are running out of travel. In this situation, you want to reduce bump stop to give the springs more travel.

Also, whether you add/reduce bump stop or ride height will depend if you're bottoming out mid-corner or on a straight. Mid-corner you'll want to reduce bump stop (if you have enough clearance) then increase ride height.

On A straight bottoming out, just add some bump stop.

Mahjik
19-11-2017, 01:17
There are many ways to attack bottoming out *if* it's a problem. When it's a problem if it's hurting your top speed and/or stability of the car. In short, don't try to fix something that isn't a problem unless you've identified it's a problem. In some cases, bump stops will help. In others, ride height, stiffer suspension, lower aero or a combination of all of the above may be needed.

CDubLDD
19-11-2017, 01:21
There are many ways to attack bottoming out *if* it's a problem. When it's a problem if it's hurting your top speed and/or stability of the car. In short, don't try to fix something that isn't a problem unless you've identified it's a problem. In some cases, bump stops will help. In others, ride height, stiffer suspension, lower aero or a combination of all of the above may be needed.

It hasn't affected the way the car handles. Just wasn't sure if the flashing red needed to be completely eliminated. Thanks for the reply

CDubLDD
19-11-2017, 07:27
Another question I have...On the telemetry screen when I am looking at the springs (parked and not moving on track), do I add the bump stop and travel and make sure the height is above that? Do I want the travel + bump stop to equal my ride height? I'm not exactly sure what I should be looking at right there

hkraft300
19-11-2017, 10:48
Height is your ground clearance I believe. Although, in PC1 some cars (Merc CLK-LM) has mandatory skid plate that forced a 30mm minimum ground clearance. So when, in PC1, your height =30mm, you were actually scraping.

Travel is how much your springs can move/compress.
Bump stops sit above your springs and provide extra cushion and height.

CDubLDD
19-11-2017, 16:27
Sorry. I should have explained that I know what each one is. What I am trying to find out is how do I set them up. For example, if my height is 4.4 in and my travel is 3.4 in and the bump stop is .7 in, do I reduce the bump stop to make the height just slightly above the travel? Or do I reduce the height to make sure it's slight above the bump stop + travel? Or can I just reduce the height as far as it can go (without scraping)? Is there some sort of general rule when it comes to suspension? If I soften the springs do I want to lower the height? Or if I stiffen them do I want to raise the height? Those are the things I am needing help answering

Mahjik
19-11-2017, 17:37
CDubLDD, it's not that simple which is why you aren't getting a lot of replies. There is no direct formula as each change can have a consequence on something else. It's more of a black art of experimenting and what suits each driver.

Some cars are more sensitive to underbody air travel than others, so adjusting ride height and rake will have large consequences. In short, you typically want to run cars as low as possible without affecting handling and/or top speed. You then adjust everything around it to support your ride height. Large amounts of aero will push down on the car so you may need to run less aero, but that can make the car harder to control. You can also counter it with firmer suspension, but that can also have consequences of making the car harder to control on the edge or not able to handle a bumpy track..... and so on..

There is no script to these settings.

hkraft300
19-11-2017, 19:02
. For example, if my height is 4.4 in and my travel is 3.4 in and the bump stop is .7 in, do I reduce the bump stop to make the height just slightly above the travel? Or do I reduce the height to make sure it's slight above the bump stop + travel? Or can I just reduce the height as far as it can go (without scraping)? Is there some sort of general rule when it comes to suspension? If I soften the springs do I want to lower the height? Or if I stiffen them do I want to raise the height? Those are the things I am needing help answering

I reduce bump stop but keep a few mm, and also try to run minimum height. Generally, but hugely dependant on what and where you're driving.

GT3/4/E cars you can drop the ride height and rarely scrape.
LMP cars make a lot of downforce so, if you ride then low, you have to keep the springs stiff enough to hold them up against the Aero load. But then are you getting the Aero grip benefit to counteract the loss of mechanical grip from stiff springs?
Open wheel Indy and formula Renault, for example, are very sensitive to ride height, rake etc and have very soft tires. To hell with mechanical grip: it's all about the Aero.

What Mahjik said: there's no hard and fast rule.
You're best to learn how each component works, what it affects (every tuning change affects everything else in the car, sure or not), experiment.

CDubLDD
19-11-2017, 20:48
I reduce bump stop but keep a few mm, and also try to run minimum height. Generally, but hugely dependant on what and where you're driving.

GT3/4/E cars you can drop the ride height and rarely scrape.
LMP cars make a lot of downforce so, if you ride then low, you have to keep the springs stiff enough to hold them up against the Aero load. But then are you getting the Aero grip benefit to counteract the loss of mechanical grip from stiff springs?
Open wheel Indy and formula Renault, for example, are very sensitive to ride height, rake etc and have very soft tires. To hell with mechanical grip: it's all about the Aero.

What Mahjik said: there's no hard and fast rule.
You're best to learn how each component works, what it affects (every tuning change affects everything else in the car, sure or not), experiment.

This is very helpful. Thank you. I'm a noob when it comes to setups so any advice is appreciated