I’m new to tuning, and I’m having a problem with understeer in my 1993 Nissan Skyline GT-R V-Spec (R32).
I’ve tried tuning the differentials and springs and ARBs but nothing works.
The interesting thing is that when I brake, it oversteers like crazy. Any ideas how to fix this?
Also, how do you all tune AWD for all-around? I threw myself into it before I looked at how to begin tuning for all-around AWD cars. Any recommendations on what I should/shouldn’t do?
Any and all help is greatly appreciated!
With the differential, try the following settings: 35/0 75/15 60
Ok, let’s begin with the simple questions and work from there. You are having a problem with understeer, ok. What exactly do you mean - understeer on turn-in, mid corner understeer, understeer on corner exit, is it on-throttle understeer, off-throttle understeer, understeer with constant acceleration? First you need to identify where the problem is so that you can look at what to do to fix it.
Ride Height: What is the ground clearance of the car in the front and the rear. The variance in ride height can affect the handling of the car because it alters the airflow beneath the car. According to McLaren, the front end of the 675LT was “lowered by 20mm while rear ride height was unchanged because this creates an (obviously) raked stance which evacuates spent air from under the car faster and that somehow equals more downforce” [Source: Motortrend May 2015, Vol. 67 No.5 pg 54)
Anti-roll bars affect turning behaviour off-throttle and on corner entry and exit.
Springs affect turning behaviour on-throttle.
In Forza the damping settings pretty simple and basic. Think of the damping as fine tweaks to the springs and suspension. Bump is responsible for the vertical motions while rebound does the horizontal motions.
Rebound affects transitional characteristics of the car so mid-corner behaviour and behaviour of the suspension as you go from on-throttle to off-throttle or vice versa.
Bump affects how the car handles over bumps.
Here is a generic base tune you can try to assist you with an AWD setup on the Skyline.
Tire Pressure @ 28.0 PSI
Lots of negative camber up front with about a half degree less negative camber out back.
Toe out up front and toe in at the rear.
The more negative camber you run the less caster you need.
Low front springs with rear springs roughly 50 pounds stiffer
Front ride height 0.1 lower than rear
Very soft front anti-roll bars and very stiff rear anti-roll bars
High rebound and low bump OR Low rebound and high bump (always have more front bump than rear)
Differential: 35/0 75/15 60
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Mostly on-throttle, mid corner understeer. Sometimes it understeer on turn-in, but that’s mostly between 40-70 mph
This link can help you out as you play with things: click here
If you are having issues with low speed turn in response you can try the following:
- Increase the amount of negative camber on the front axle
- Try increasing the front axle Toe angle
- Drop the front ride height so it is lower than the rear ride height
- Lower your front anti roll bar setting.
If it’s mostly on throttle understeer then your front suspension is probably set too stiff, try lowering your front springs and see how that feels.
As far as any understeer occurring off throttle probably results in your anti roll bars being set too stiff up front.
If you’re having understeer at 40 - 70 mph, are you braking or accelerating? That’s fairly low-mid speed, try looking into your alignment settings for any adjustments to be made here 0 as well as those anti roll bars.
Try the link it really helps.
Some things to keep in mind in this game are that you can run an insane amount of negative camber. If you choose to do so, then I suggest you go through the in-game explanation of caster and read it very carefully.
-----> [If I tell you that I can add 3 to 2 to get 5, then what else can you learn from that statement.]
Try setting your anti roll bars to some fairly extreme settings one way or another and see what happens. I used to make some pretty good cars. I also used to get told by a friend that my anti roll bars sometimes weren’t extreme enough but I thought I knew better. Trust me - experiment with extremes.
The link I gave you has you increase your rebound damping to fix understeer. The game tells you to decrease rebound to counter understeer. Thing is that the link assumes you have two way adjustable damping settings (a low speed and a high speed) whereas in the game you only have one setting for both.
Leave the rebound setting as an adjustment for horizontal suspension effects. Use it to adjust how a car behaves while turning. Use the bump setting to fine tune adjustments to how the car handles over bumps - the game does very well with a very low setting.
Rear bump helps with rear end control.
Higher front rebound helps with rear grip.
Try getting another R32 and set it up along the guide lines I posted in my first post and see how that feels. Without going into exact numbers, I can tell you that a similar set up on my R32 feels fantastic and on the R34 results in a car capable of placing within the top 10 on the leaderboards.
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Thanks PPi, learned a little something again today. Always looking to learn.
Just curious as I also like to learn and many a thing in this sub-forum can be turned into a learning experience. What did you learn? To be more specific:
- what were you doing before
- what did I write that helped you out
- how have you made changes and what have the effects been
Sometimes, it can be as easy as slowing down to read something and taking the time to make sure you fully comprehend it.
Since this thread isn’t getting many views and I’m kind of going down this path, I’ll hide this gem in here.
Hopefully, if I can explain to you visually that 3 and 2 make 5 you can take away that 3 and 2 make 5. However, would you necessarily understand that 5 take away 3 is 2 and that 5 take away 2 is 3? Would you understand this on the first try? Would you understand it quickly glancing over the math equation in a book?
Well, I saw something on a build that was open sourced to me a while back and then it was brought up a couple times by the same individual. It happened to pertain to a tuning component I struggled with and did not understand. I had several reference materials to help me as I went along but I could just never get this one setting to click. Then I decided to go back to the tuning tips in the game and read what the box says. The box in the game doesn’t say much but it’s important to note what it doesn’t say because that’s equally, if not more, important than what is written.
This is a great link to use, but it doesn’t teach you. It is nothing more than an input output table in diagram form.
[This page](http://www.rapid-racer.com/suspension-tuning.php#Damping/ Bump and Rebound) will help you with your understanding. Check the camber, toe, and caster settings in particular and start to assemble a bigger picture.
Now, go to Forza and open the tuning menu. Go to the alignment section and see what it displays for caster:
This is what I wrote to someone regarding it earlier:
It’s such a little detail, something so minor and tucked away and hidden that it is very easy to miss. Clearly, some of the best (such as SatNiteEduardo) have picked up on this early on in FH2 but he’s been tuning longer than I have and understands the concepts better than I do. Several times when he’d give me advice it would be along the lines of “this is what I did, this is why, do this” and it didn’t come with much explanation or insight behind it, it was always “this works, do it”.
Anyways, now that I finally, finally, wrapped my brain around that and comprehend it, I can see the relationship that it creates between the camber and caster sliders and how to effectively use them together to build a better car instead of having those settings fight against each other.
What I’m really getting to here after all that is, that’s why I’m curious what it is I said that helped you. I want to see things from another perspective. I’m also not perfect and you may be doing something that works better than what I do, or that I like, or it could even help others understand it better so I want to know what you were doing before, how you do that same step now, and the process or changes that led to it. It should also help VenomWolf77 now that I’ve sort of stolen his AWD Skyline thread and turned it into general AWD help. (Bad Kitty, no!)
Cheers.
Here’s the best way I can describe how you helped me…not only in this thread this week, but there was another last week where you and SatNiteEduardo were dropping PSI and camber advice…
I take everything I read, then read it again. Then read it again to retain it. The “checking extremes” portion…taking -camber further than I have been…tweaking the toes, and the caster. Indeed your math formula makes sense to me. By dropping PSI slightly less than what I had and taking the camber further than -2.5, I have been able to stick to the road better into and out of turns. I feel like I was keeping my front ARB a little high also. One thing that I did keep unchanged was how I disperse differential settings. I can’t (for the way I drive) keep anything on the bottom slider of the rear decel. I keep it anything above 0, and I get too much pedal lag. I noticed the bottom number --if I turn it too high vs my normal setting, I lose time on the 0-60. Most of my tuning lately has been into A and S1, Pre-1970 cars. I have been rolling this… 42/0 80-85/0 60-67 Anything higher than the 67 and the car gets slower. When I feel like I have the suspension figured out I then move to the gearing. Been experimenting with the 1-2 shift lately. Seeing if having a short 2nd gear into 3rd is more valuable to how I drive vs having a tall 1st and 2nd.
Gearing is where I struggle honestly. I don’t often use the race transmission but if I do I let a gearing calculator do the math for the base of the transmission. Then I drive the car and make changes based on what I need.
When I do my tune, I don’t mind losing a little bit on the 0 - 60 time because for me the 0 - 100 time is more important. Even then, it’s not a good number to look at because the key stat in a 0 - 60 time is that 0. 0 meaning you aren’t moving and are completely stopped and that’s great for stoplight battles, drag races, and the starting line. Afterwards there is (unless you wreck) never a time that you are standing completely still. 5 - 60 second times or the rolling start test would be a much better metric to display but we don’t have that in Forza. The rolling start times tend to be slower than the 0 - 60 times. the same applies for the 0 - 100 time. In the race, you want to maintain the highest average speed, right?
Based on the premise of the thread and your differential this is for AWD cars. I have been running between 55 and 65 on the torque split. On occasion I’ve gone to 70 to give the car more of a RWD feel but that’s usually if everything else has resulted in understeer.
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I understand gearing a lot more than suspension. I was noticing on lighter cars yesterday that keeping the split closer to 50 vs higher than 62-63 causes the car to be more stable, and also keeps the 0-60/0-100 time closer to where I need it to be. I don’t think the lack of weight or wheel base on the old Ferraris (save for the GTO) help this at all. I have been trying to keep it all my gearing at 4.11-4.40. I like to launch. If I can get ahead of the riff-raff of rookie drivers, smashers, and dirty jerks ahead of the first turn and out of it, I don’t have to worry too much other than screwing myself up. I notice most of the time I am in 2-3 for in and out of turns also, so it’s important for my own tuning that I have those dead on. 5-6…I still feel like I am learning this from the very start of my playing this game. They are formidable how they are–but I feel I can get another couple MPH out of most of my cars.
Speaking to the 0-60 times…we are talking for me usually the difference of .01-.3 sec. I mean the car can only do so much. It’s up to me to figure out the magic! I understand what you are saying about the 0-100 also. I notice those times change almost in concert with the 0-60 times. PSI being taken away from my tires-- <28psi—has actually helped with these times.
I’d love some help figuring out the gearing but that’s for a whole other thread of PM.
You’re saying the AWD cars tend to be more stable with the torque split set closer to 50 than closer to 65 if they are “lighter”. Please define “lighter” and what do you mean by stable? I only ask because I’ve heard it used a couple of different ways here in the past. For example, I’d say Eduardo’s tunes and my own are stable but have good turn characteristics and yet some people might call that unstable.
If nothing else works or I just need that little bit extra, I use the PSI to help out. I have found that I typically don’t like going higher than 28 but I have on occasion put the fronts to or the rears to the 22-26 range but only one axle, it’s never been both together. Well, if I go less than 28 I might go less on both axles (very rarely) but then I stagger them so they aren’t the same PSI. Most common would be a 26/28 split.
Honestly, I’m still curious if the OP tried my suggestion for tuning the car and what s/he thought about it.
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Lighter for me is the 2200-2800 lb range. Those little roadsters while seeming grippy, because of the weight/wheel base, one little blink at the wrong time, and it seems like it’s over for me. Love a challenge and will continue to work. I also have been keeping the front PSI .5 above the rear. Enables me to get the back end of the car out a little quicker when I want to.
If the car is loose and you like the stability in the straight darting in and out of traffic, try adding .2-3 stagger in the rear. Helps keep the car stable.
Good tips
the most effective way is to make your springs softest as possible, widest tires, and it’s much better if you have Storm Island DLC because you can use the rally springs, tune it to softest and lowest height possible. Tried it on multiple maxxed out to S2 & XXX cars (240Z, 918, 240SX, GTR, Sagaris, F150, Rally Fighters,Esprit, and what not). The setups are really fun to use to maneuvering between trees and plains, good handling, and mostly fit any cars. at least for me. Just try it, you might like it. who knows?
