What's the one suspension setting you have the most difficulty with?

[Terry Rock]

I always tend to dial out rear toe-in.
Though it's there to allow more stability under braking and to aid in tracking out of corners, I always suffer with a perceived instability.
I spent most of my life driving first karts...then rear engined, rear-wheel drive cars.
I tend to love over-steer more than under-steer, since it's what I became accustomed to right from the very beginning.

 

[Richard Dastardly]

They will for sure at high speed, out of corners the 330 P4 out accelerates those other 2 though. I guess if it had a roof it would destroy them at high speed as well! The GT40 does understeer a bit in AC but the 330 P4 is on another level IMO

I posted a stream onboard the 330 from our last WG event on YT ( here: https://www.youtube.com/channel/UCbimm1M0Y7ZzBEwxGEwvZ7A ) - unfortunately I can't embed a link starting at a specific time, but iirc 40 mins in is the best lap. Understeers up the WG esses but so does every other car, honestly - other than that it just has a tendancy to slide all 4 wheels outwards. The default setup is really that rubbish. My driving isn't great, but still

 

[Andy-R]

If you drive all 3 through Vialone at Monza Road Course you really get a sense of how much more the 330 P4 understeers at speed! It could just be that it understeers a lot more on throttle I'm not 100% sure as I tend to take the GT40 normally. IIRC when I drove the 330 P4 at Silverstone 1967 off the back of driving the GT40 there it felt really understeery again.

You can kind of see it in the split 3's below. Those last 2 corners are the 2 main mid/high speed corners of this track and the Ford is much closer through sector 3 than sectors 1 & 2.
http://www.radiators-champ.com/RSRLiveTiming/index.php?page=rank&track=5124&car=2171
http://www.radiators-champ.com/RSRLiveTiming/index.php?page=rank&track=5124&car=5896

 

[Richard Dastardly]

I did a race at Riverside long in it - trying to get it through the left off the back straight was a real trial, but the esses were easy to deal with. Roughly the same setup did a 33.3 at Brands in a race too, so it wasn't some quirk

Never tried a proper hotlap session in that car, I don't really have the patience for it.

 

[Andy-R]

Woah if it can't get through that kink flat out then it really has got high speed understeer issues! I use those 2 tyre marks that are more or less in a line as a turn in marker for that kink. The GT40 goes through there without drama.

 

[Richard Dastardly]

Woah if it can't get through that kink flat out then it really has got high speed understeer issues! I use those 2 tyre marks that are more or less in a line as a turn in marker for that kink. The GT40 goes through there without drama.

Was easy with a new setup - arriving at that point was interesting though. IIRC with the default it'd go through flat but use all the road, same as T1. The 330 was one of the cars that responded to very stiff ARBs.

 

[Danny kung]

The mid/high speed understeer in that 330P4 is nasty! It isn't bad at low speed and it dominates the competition under braking and acceleration (until you get above 120mph or so) but I'll take the GT40 over that thing every time! IIRC I tried slamming the front end and raising the rear to try and reduce understeer (purely because something similar worked in the T70) but I ended up filing the 330 under rubbish and moving on to more enjoyable machinery.

I'd place bets fiddling with the differential and/or the ARBs then adjusting your driving style will sort it.

 

[Andy-R]

I don't think your going to driving style your way out of the understeer in that car. You might make it a bit more tolerable with some setup changes. Try taking Vialone with a little 50% lift like in this car (@1min) or the GT40 and you'll probably end up in a hedge.

Spoiler: 908

 

[Richard Dastardly]

Needs a slightly longer lift, but it's ok through there. Still definitely has aero lift issues.

 

[Danny kung]

Well I only have the base game so I can't try it out. But I'll try my theory out on any base-game car/track etc that has terrible understeer. default settings?

What I mean by driving style was more subtle...like instead of getting on the throttle early, you'll do more trail braking or something.

 

[dud]

I'm fine with balance & not bad with dampers these days, but absolute values for some things still puzzle me - like ignoring any front/rear balance, what is the difference in performance between low ARB settings & high? when would you want more overall body roll?

A softer roll bar maintains more contact patch with more pressure on the inner wheel. Since they can be individually adjusted this is most often used for front/rear balance in corner.

But the same effect is there when you make both softer. You lose less contact patch in corners. That raises your friction.

The reason why you don't just make every car very soft (aka just remove the bars) is that body roll comes at a cost - the energy to compress the springs, and the difficulty to control where that same stored energy goes when the lateral force goes away. You might be able to do higher Gs on average in the corner, but you also want a predictbly behaving car sitting at the corner exit ready to pounce. Aside from the energy stored in the springs you also have the problem that you body is still rolled when you straighten out, so now you lose traction as tire load evens out slowly.

 

[Andy-R]

Well I only have the base game so I can't try it out. But I'll try my theory out on any base-game car/track etc that has terrible understeer. default settings?

What I mean by driving style was more subtle...like instead of getting on the throttle early, you'll do more trail braking or something.

For those mid/high speed corners where the 330 understeers more in comparison to the GT40 and 908 I think all you can do is to ease off for longer, slow the car more and/or get on throttle later. I'm not really looking for a setup for it I was just (or so I thought) agreeing with the other guy about the 330.

 

[Richard Dastardly]

For those mid/high speed corners where the 330 understeers more in comparison to the GT40 and 908 I think all you can do is to ease off for longer, slow the car more and/or get on throttle later. I'm not really looking for a setup for it I was just (or so I thought) agreeing with the other guy about the 330.

It is mostly default setup, and partly the inherent car behavior. I have a setup with a lot of rake that is a handful in the Parabolica that will go through Vialone with not much more lift than the 908, but I wouldn't want to drive that setup at any more complicated circuits. If you use something realtime like camber extravaganza you can see the front tyres hopping in the corner,...

Here's another one - front toe on race cars. I have some idea of what adjusting it is meant to do, but I generaly end up adjusting it for tyre heating unless it's a car with really limited available adjustment. Is it one of those really subtle effects that only show up on telemetry when you can tune everything else?

Talking of telemetry, @RasmusP you were offering Motec workspace & a brief guide?

 

[Pawel Ziolkowski]

A softer roll bar maintains more contact patch with more pressure on the inner wheel. Since they can be individually adjusted this is most often used for front/rear balance in corner.

But the same effect is there when you make both softer. You lose less contact patch in corners. That raises your friction.

Nope, not at all. Both ARBs softer means in corner nothing has changed besides roll angle, contact patches remain the same size.

The reason why you don't just make every car very soft (aka just remove the bars) is that body roll comes at a cost - the energy to compress the springs, and the difficulty to control where that same stored energy goes when the lateral force goes away. You might be able to do higher Gs on average in the corner, but you also want a predictbly behaving car sitting at the corner exit ready to pounce. Aside from the energy stored in the springs you also have the problem that you body is still rolled when you straighten out, so now you lose traction as tire load evens out slowly.

The energy stored in springs and ARBs stays the same as long as the lateral g-load is constant, and energy release mechanizm for ARBs is basically the same as for springs.
What you probably meant was energy stored in inertia. Then yeah softer ARBs would mean more energy is stored, but only for a very brief moment - it won't wait till we reach corner exit and lateral force goes away.

 

[Neilski]

What's the net effect if you soften both ARBs and stiffen all four springs by a matching amount? (Or vice-versa...)

I guess some things will be the same (like, I think, cornering on a smooth track), but I suspect that the car should behave differently over bumps.....?

 

[Richard Dastardly]

What's the net effect if you soften both ARBs and stiffen all four springs by a matching amount? (Or vice-versa...)

I guess some things will be the same (like, I think, cornering on a smooth track), but I suspect that the car should behave differently over bumps.....?

Fore-aft weight transfer behaviour changes for one. All your dampers get out of sync is another

Having read up a bit it does seem like stiffer ARB is generally better for race cars up to the point where the ARB is stronger than the springs ( because at that point the inside suspension starts acting a bit oddly with a lot of load ), if the track is smooth and you're not riding kerbs. Stiff ARB will transfer the effect of road bumps ( or kerb riding ) across to the other side of the car, so on bumpy circuits you will want to back off - unfortunately you'll want to back off the springs too, so that presumably becomes an interesting damper-based challenge.

Oddness like the ARB overwhelming a spring does not seem like something you could pick up from just driving, so I guess that's a telemetry thing, if that sort of detail is modelled in AC.

 

[Pawel Ziolkowski]

If you have heave spring you can throw normal springs out and basically drive all the bumps on ARB's. In this case the ratio of ARB to spring would be infinity which would definitely count as overwhelming and that's actually how front of the tatuus works.

Thou the the odd feeling when driving that car is more due to front having no roll damping.
I suspect that if we made a car with both front and rear with one heave spring, one ARB and without any normal springs at all, but left dampers as they are (1 per each wheel) it could be indistinguishable to a "normal" car. (and highly impractical in construction)

From what i understand atm, absolute arb values are a bit like dampers... there is a correct ratio of their stiffness to springs, so if we stiffen the spring we want to stiffen the dampers and arb's to match. Thou what ratio of spring to arb is good is beyond me.

 

[Neilski]

Fore-aft weight transfer behaviour changes for one. All your dampers get out of sync is another

Everything you said sounded highly plausible except the fore-aft behaviour changing - I would have thought that would be the one thing that couldn't change, because I thought ARBs only affected lateral transfer...?

 

[Pawel Ziolkowski]

Everything you said sounded highly plausible except the fore-aft behaviour changing - I would have thought that would be the one thing that couldn't change, because I thought ARBs only affected lateral transfer...?

Yeah but matching spring stiffness to a given roll angle after softening ARB's means springs are stiffer so car sits higher and pitches less.

 

[Neilski]

Yeah but matching spring stiffness to a given roll angle after softening ARB's means springs are stiffer so car sits higher and pitches less.

OK, gonna have to sit down and think for a while to get my head around that

 

[Richard Dastardly]

OK, gonna have to sit down and think for a while to get my head around that

Spring rate affects both roll & pitch, ARB affects roll - so if you counter the change in roll with the ARB ( effectively keeping the spring rate the same in roll ), what's left?

Draw a quick free-body diagram, fairly easy to see.

Spring rate also changes the ride height if you didn't adjust anything