Tuning for Dummies - help needed!

  • Thread starter pmgolf
  • 42 comments
  • 7,554 views
pmgolf
I am not mechanical or skilled enough to drive each lap exactly the same as the previous one

In all fairness, put in the effort and the laps to get your times consistent, then start worrying about setups. You're not going to learn/succeed much otherwise.
 
I hate to say it but he's right. I'm only moderately consistent and I can run laps within 0.750" of each other, usually, with the occasional magic lap or (more likely) miscue. But the good guys that I discuss tuning with strive for consistency on the order of 0.200" or better.

The way to get reasonable tuning results is to be fairly repeatable so you can see if your adjustments are helping or hindering. Just like a good golf swing.
 
Duke
I hate to say it but he's right. I'm only moderately consistent and I can run laps within 0.750" of each other, usually, with the occasional magic lap or (more likely) miscue. But the good guys that I discuss tuning with strive for consistency on the order of 0.200" or better.

The way to get reasonable tuning results is to be fairly repeatable so you can see if your adjustments are helping or hindering. Just like a good golf swing.
Um actually, Mr Admin sir, he is wrong. I laborously posted a detailed tuning guide that relies very little on skill; it uses direct feedback and observable results to make adjustments. Its main tool incorporates the lap ghost, and the ghost doesn't lie. When you make an adjustment, then hit the start/finish with the exact same acceleration (that would be "hold gas button firmly, steer through sweeper," pretty easy), any terrain induced differences in acceleration will show like litmus paper when your ghost pops in next to you. One click in compression damping can easily be half a car length. And if you think that is good, you should try chasing your ghost for a lap while packing a new adjustment.
Now, Balfa, in case you have yet to learn this, one car length for a couple hundred yards multiplied over the length of a course equals many seconds saved for an empirical (relatively skilless) test. In other words, an unskilled driver in a tuned car may be able to crash and recover many times while a skilled driver must drive slower because his untuned car takes wider lines...

Imagine what the ghost could do for your swing.

The guide, in case anyone is curious, is currently buried on page 3. Please post a comment if you think it merits dredging it up from the archival abyss.
https://www.gtplanet.net/forum/showthread.php?p=1562715#post1562715
 
Balfa
In all fairness, put in the effort and the laps to get your times consistent, then start worrying about setups. You're not going to learn/succeed much otherwise.
One race later and I am having misgivings. Perhaps I was too harsh, I apologize.
I remember my very first GT drive, it was the green RX-7 LM, on what must have been SS Rt5, and I couldn't even keep the thing pointing forward - I HAD to have this game. I got home and something just wasn't right... "You mean you have to TUNE THESE FRIKKIN THINGS?!" To my dismay, I learned I had to work before I reaped my enjoyment of mastering the RX.
And that is the way it is with Gran Turismo, it is not like other simulators where you get in, pick a song and mash the gas. I think it is a given that people who are here posting questions are already in the ADVANCED class when it comes to succeeding at Gran Turismo because they recognize there are so many factors affecting the consistently low lap times we ALL want to achieve. So please, sit back, read some posts, get to know the place and let's work on those lap times TOGETHER.
 
Nice to see that some of our members will actually think about what they've written - well done Aarque for pondering your words and realising that what you'd typed might well have been different to what you meant. 👍.

It is a tuning truism that until you've driven a car stock and then added your 'performance' parts and driven it some more ... and some more ... and some more ... until you can get 1/10th consistency out of it, then you will not really be able to tell if any tuning adjustments you make are of benefit or not.

This is even more evident in GT4 than in GT3 as in this game it is possible to imperceptibly take a corner better or worse and have your times vary by quite a margin. Thankfully, once you know how a car 'feels', it is relatively easy to tell if a set-up is worse than before so what takes the time is gentle honing of a suspension suite that really gels with your driving style. Again thankfully, once you've done a fair bit of spannering work then the time it takes to fettle a vehicle into shape reduces but you're still looking at a couple of hundred miles under the wheels to sniff out all those elusive tenths :D.
 
I really enjoy reading the theory guides to tunning. However, rk's guide is the best "how to go about setting up your car guide" I,ve read.

The one thing missing is "what car"?

Can anyone suggest a car that handles like a dog but with a few simple changes would have a very noticeable improvement.

rk likes to use Deep Forest, any other trackes that make good tunning testing?

Cheers JT Fox
 
sukerkin
...In (very) rough terms, the Front Bound and the Rear Rebound affect corner entry whilst the Rear Bound and Front Rebound affect corner exit.

Sukerkin, if you see this, could you elaborate on the above a bit? Exactly how do they have their effect?
 
Zardoz
Sukerkin, if you see this, could you elaborate on the above a bit? Exactly how do they have their effect?

When it comes to shock tuning no one here knows more than Ol' Sukerkin!
He has shown me, and many others, the art of shock tuning. The bad thing is, I never see him posting in GT4.. :(

We have had some interesting discussions in the past in the GT3 forum regarding shocks and he has also directed us to the Smithee's Race Car Tech site which is definately the best guide to tuning I've read..

Though, I visited the site while typing this and found that they had removed the guide from the Homepage, so there is no link to click on, but it is still most definately there.. refer to the links at the bottom

Let me try and answer your question..
In keeping with the threads focus on simplicity, Front Bound and Rear Rebound effect the 'speed' of which weight is transfered to the FRONT of the car (corner entry). Changes to the Front Rebound and Rear Bound effects the 'speed' of which weight is transfered to the REAR.

The slower the weight transfer is, ie stiffer damping, the more stable the car may feel. If the weight transfer is too slow, you may not get the right amount of weight and grip you require over that end of the car.. resulting in a sort of delayed form of under/oversteer

The faster the weight transfer is, ie softer damping, the more unstable the car feels. If the weight transfer is too fast, too much weight too quickly has been transfered resulting in excessive under/oversteer


For example when you brake approaching a corner the front of the car compresses (Bound) due to weight transfer and the rear decompresses (Rebound). If the rear decompresses too fast the rear end looses too much weight and grip. Increasing the Rear Rebound will mean more grip at the rear for a longer period (we're talking milliseconds here).

So, if under braking there is more weight over the rear, the rear will tend to try and assist with the steering, due to lateral (sideways) forces, and "rear steer" the car which will help during corner entries.

Having a stiffer Rear Rebound also means that during corner exits the rear decompresses slower and keeps weight over the rear tyres for longer meaning greater "power down".

Therefore, having a Stiffer Rear Rebound will assist with turn-in and allow for more grip and control on exits


Remember though, there are many other factors to consider..




Hope that helps, if not, these links sure will. :sly:

Are damper settings supposed to be stiffer at the front??
https://www.gtplanet.net/forum/showthread.php?t=53538

Shock Tuning

http://www.smithees-racetech.com.au/theory/shocktune.html
http://www.smithees-racetech.com.au/theory/shocktune1.html

Start here for a guide to Racecar setups
http://www.smithees-racetech.com.au/theory/
 
TRANNY TRICK ? How do you do it? What For? When should it be applied? I see this all the time and would love to understand it. Thanks.
 
Hi chaps

Many thanks for the kudos, Kai. It's very nice to hear that I've managed to help someone get a grip (yeah, automotive pun :)!) on the arcane art of tweaking dampers and it's even better to read their coherent and informed thoughts as they respond to a question 👍.

I was just searching through some related threads, looking for supporting evidence to a post I was making on the old chestnut of "GT4's Suspensions Work Backwards", when I came across this and saw Zed's query.

Kai's answer is excellent {:bows in respect:} and I think I'm a bit too late after the question was asked to make a meaningful contribution now - sorry :embarrassed:.

I am taking a long hard look at Damper Tuning in GT4 at the moment and am starting to come around to the point of view that there is something astray in either what the tuning 'sliders' are altering or in the way the game interprets those inputs. The huge grippiness of the tyres muddies the waters somewhat as it masks what is actually going on in the suspension and makes analysis very hard (especially as it also causes anomalous differences between high and low speed cornering) :(.

I'll post some kind of 'report' up when I get around to finishing the research, just in case of the unlikely event that I come up with something that hasn't been covered yet in the torrent of GT4 related posts :lol:.

The good news is that at least dampers still have a major role to play in dialing in a cars handling in GT4 ... I'd be somewhat upset if I couldn't fettle my dampers to good effect when the mood takes me :D.
 
As promised here is a 'report of some kind' with regard to some experiments in how the chassis and suspension adjustments in GT4 appear to work. It's a bit disjointed as it was written over a couple of days and sees my opinion waver from 'somethings astray' to 'things're okay' :D. I hope that it'll be of help to someone anyhow, particularly as it stays (mostly) away from technical language and focusses purely on empirical observation.


-----------------------------------------------------------------------------------------------------------------


Trying to tune up an Aston Martin Vantage so that it's fun to drive.

It has lots of weight and wags of torque, which means that it spins up the rears very easily in low gears and punishes tyres.

Trying some experiments with Dampers to see what effects changing just those has on the handling of the car. The circuit is High Speed Ring and the tyres are feeble S2's (feeble with all that weight on them at any rate :D).

I found early on that there was high speed understeer (in the fast sweepers) and lift off understeer too (in the slower corners lifting the throttle did not encourage the nose to tuck into the line).

I set the Bound at a level 6/6 and tried the Rebound at a traditional 9/8. The understeer noted above was the result. Tried 9/10 and found that straight line speed was improved (huh? Might be better traction on corner exit) but the cornering understeer was more pronounced. Cut the Rear Rebound to 6 and found that the car was much more inclined to turn and hold tighter lines. Cut the Front Rebound to 6 and found that the understeer came back. A setting of 8 was pretty good. 10 seemed an odd mix where sometimes she would really cut a good line and other times the load on the tyres seemed too much and she'd run wide. There did seem to be a modicum of throttle steer available too, if you didn't go too mad with the loud pedal too early in a corner.

Put the Rebound back to 8/6 and try increasing the Rear Bound. It seems to increase entry oversteer but also increase exit understeer. Swap it around with 8 Bound at the Front and 6 bound at the Rear. It was a case of more understeer going in (as if the tyres were being overloaded under braking) and more oversteer coming out. Try 4/6 Bound (with 8/6 Rebound). Not bad handling actually. I was able to use power oversteer to control my exits from corners quite nicely and didn't find corner entry understeer too much of a problem if I braked properly (she would wash wide if you didn't get down to a slow enough speed for the tyres). Back to 6/6 Bound and 8/6 Rebound for a comparison run as I've gotten faster and faster laps as I've gone and want to make sure it's hardware changes rather than wet-ware improvements :).

It feels like a swings and roundabouts deal, 4/6 gives you more oversteer on exits and thus more speed into the straights whereas 6/6 gives you more stability into the corners and thus allows you to set your apexes better. They're about as fast as each other but the 4/6 is marginally quicker in the laps I've run.

I'm noting that these observations do not correspond with accepted tuning wisdom from the real world. It is in fact backwards as Front Bound and Rear Rebound are supposed to come into play during corner entry and Rear Bound with Front Rebound are the controlling factors on exit. For oversteer on entry and exit I want Soft Bound and Stiff Rebound at both ends. Try her with 3 Bound and 9 Rebound to see what I get. I could feel the oversteer was there actually, it was especially noticible in the slower corners. The laps were much slower however. Invert it to 9/9 Bound and 3/3 Rebound. I can feel the general understeer there but it seems also to translate into more grip and so lap times are not too far off what I was getting before with 6/6 and 8/6.

Put 4/6 and 8/6 on for comparison run. Faster than both the 'extreme' settings. Ah, a spanner in the works is that the HP has dropped. Oil change time. There is without a doubt more corner entry understeer with this set-up and more corner exit oversteer (especially on the power in an FR car).

I wonder if this is an opposite corners situation? Try reducing the Rear Rebound to match the Front. Much slower. There is an appearance of mid-corner understeer which means you have to throttle off. Back to 6/6 & 8/6 and got my fastest lap and a definite impression of more exit understeer but more 'bite' going in on the brakes.

The basic canon of knowledge is that if I want more oversteer on corner exit then I should increase Front Rebound and reduce Rear Bound. Try 6/5 and 9/6. I got more exit understeer, I'm positive of this. Assume that PD have coded it so that lower numbers mean slower Rebound i.e. more resistance. Keep Bound at 6/5 and put Rebound to 2/4. I got more exit oversteer and more corner understeer. Case almost proven to me I reckon. Reduce Bound to 4/4, 6/6 and 7/7 (three seperate sets of runs) to see if the 'inverse stiffness' applies there too i.e. that a lower number means a slower response. 6/6 was by far the best set and produced my fastest time so far. There seemed less grip and more tyre noise with 7/7 somehow and I didn't like the cars response at all. I would guess that means that high Bound values mean stiffer shocks (as per 'reality').

The cars weight is 1635KG and I'm running springs at 14.0/14.0. Maybe 16.4/16.4 Spring Rate is an interesting experiment? Feels more stable but is not quite as fast. Perhaps the springs are overpowering the Dampers? Assuming inverse Rebound then I'm running total shock stiffness of 15 at the Front and 13 at the Rear. Put the Spring Rates to that and test. Get more understeer. Try for a while and get used to it but it's still slower than the 14.0/14.0 I had originally. Put 16.4/16.4 Springs back on and adjust dampers to 7/9 & 2/4. Not too bad for feel and handling but slower than before. To check for any degradation of the car, put it back as it was. Not as good now ... give up as I'm too tired to drive with delicacy and am trying to force it. Ah the chassis refresh has gone. Try again tomorrow with a refreshed chassis and oil so I can compare like with like.

To recap, running the following set-up I was lapping at 1:14.0 to 1:14.1 (BL 1:13.895):

Springs: 14.0/14.0
Ride: 83/83
Damper Bound: 6/6
Damper Rebound: 2/4
Camber: 2.0/1.0
Toe: 0/0
Stabaliser: 6/6

The following gave the same:

Springs: 16.4/16.4
Ride: 83/83
Damper Bound: 4/6
Damper Rebound: 8/6
Camber: 2.0/1.0
Toe: 0/0
Stabaliser: 6/6

Changing it to the following set-up gave me 1:14.3 to 1:14.5

Springs: 16.4/16.4
Ride: 83/83
Damper Bound: 7/9
Damper Rebound: 2/4
Camber: 2.0/1.0
Toe: 0/0
Stabaliser: 6/6

The car felt very planted with this set-up but the ability to throttle steer was reduced which resulted in a tendency to push mid-corner to exit. Increasing Rear Bound is supposed to give more exit oversteer so I'm a bit confused there. Perhaps it's a case of simply too much rear grip and that's overriding the effect of the dampers high resistance? Put Rear Bound to 7. Less solid feel to handling and the tendency to run wide on exit is increased a bit I reckon (hard to tell as I got involved with 'Ghost Chasing' in the session :embarrassed:). Times similar to 6/6 Dampers. What does 9/7 Bound get me? Hard to tell; it's as if the chassis is a little confused and grip becomes unpredicatable.

Noticed that HP had dropped again, thus invalidating some of the above.

Ran with:

Springs: 16.4/16.4
Ride: 83/83
Damper Bound: 6/6
Damper Rebound: 2/4
Camber: 2.0/1.0
Toe: 0/0
Stabaliser: 6/6

Got noticeable corner exit understeer at high speed and lift-off understeer too; indicative of too much rear end grip. Stiffening Rear Bound should lessen that. Try 7. Seems worse. Try 8. Is better, I must have been getting a weird harmonic glitch with 7. The car is showing a tendency to understeer going in to a corner now. Try 9. As before when tried with Rear Bound this high, the car felt very planted but times are still in the same 1:14.3 band i.e. slower than with 6 Bound.

Try 7/7 & 2/2. Very good, as good as my previous best set. The only thing is a reluctance to take an attitude going into a corner - entry understeer.

The 'proper' cure for this is to Soften the Front Bound and Stiffen the Rear Rebound. Put Front Bound to 6 and Rear Rebound to 1. Worked quite well in the fast corners and vey well in the medium to slow corners.

For a final check, put the Front Bound to 6 but the Rear Rebound to 10 i.e. going from what may be Full Stiff in the Inverse System to what would be Full Stiff in the Orthodox System. Performed very similar times (a bit faster actually) and generally felt much freer, especially on the power oversteer and reduced turn-in understeer. The only way I can explain that is ... nope, I can't :(. After seeing some evidence that LOWER Rebound values mean Stiffer, I find here that HIGHER values give me the correct 'stiff damper' responses. The turn-in response to power was quite marked, such that I had to back off the steering at times to avoid apexing too early (that qualifies as genuine oversteer in my book).

My guess would be that the game, incorrectly, uses the ratio between the Front and Rear Rebounds to create understeer or oversteer. Swap Front and Rear values and see. The high value Front Rebound, coupled with the very low Rear Rebound, meant that Front end pointability was excellent, such that the car felt very good through the first high speed left hander (by far the best so far). Braking into corners tho' seemed to exhibit a tendency to wash wide and a reluctance to tuck the nose in, exactly what you'd expect from a high Front Rebound as you come off the brakes and steer more deeply into the turn.

The only conclusion I have at the moment is that 'lap times don't lie' and with a high torgue, heavy, FR car the fastest times I got on this track (BL 1:13.614) were from using dampers set to 6/7 & 10/2. This made the back end quite light and allowed good throttle steer as well as causing the nose to track well through the apexes of corners (altho' a bit of understeer was detected in Stage 2 of entry i.e. brakes off and steering increasing).

Springs: 16.4/16.4
Ride: 83/83
Damper Bound: 6/7
Damper Rebound: 10/2
Camber: 2.0/1.0
Toe: 0/0
Stabaliser: 6/6

In the search for some ratios I can use, the relevant car stats are weight of 1635KG and Length of 4745. The total of Front Damping adds up to the Weight of car/100 and the total of Rear Damping is about half that.

Some random notes that may become relevant:

I've noticed whilst playing the game that the Front end is given much more emphasis than the rear (such that the game takes no notice of what tyres you put on the rear when it comes to calculating A-Spec points for example).

Utterly disregarding real world information on tuning, it seems, in-game, on some cars, that increasing the Rebound value at the Rear end gives more understeer on exit and increasing the Rebound on the Front end gives more oversteer on exit (which it shouldn't be affecting really).

The bottom line seems to be that for exit oversteer you need a high Front Rebound and a low Rear Rebound. If you want exit understeer (or a sense of 'pointability') then use a low Front Bound and a high Rear Bound. For just a feel of better stability out of corners tho', just a click higher on the Rear Bound seems to help.

I think that this car is an extreme example due to it's great weight and massive torque, which the game doesn't simulate well at all, but I think the principles seem fairly clear. As a caveat, because the rest of the suspension wasn't dialed in, simply set to be stiff, the results are by no means conclusive as before you can truly fettle the dampers in the real world, you have to get your springs and stabalisers and general weight balance right first.

I will try the above procedure with another car. Keep to my favourite FR drive train but go for a lighter, less torquey model ... and one that hasn't been daubed with the Anti-Non-Nippon Dehandling Brush :D.

A Honda S2000 Type V '00. Buy all the suspenion and transmission toys and lighten it down still further (Stage 1 1260KG reduced to 1146KG, Stage 2 down to 1108KG (Stage 3 would give 1071KG but don't buy it). Put on a Racing Chip, Racing Exhaust and Stage 2 NA tune with an Oil Change (307HP). I don't know if this'll be fast enough to show up suspension changes in Turn 1 but we'll see. I was right - the S2000 handles perfectly around this track and shows no vices with Dampers at their stock 8/8 & 8/8. Perhaps a little too responsive on turn-in at high speed.

Springs:11.1/11.1
Ride: 96/96
Damper Bound: 8/8
Damper Rebound: 8/8
Camber: 2.0/1.0
Toe: 0/0
Stabaliser: 6/6

Try the same ratios as for the Vantage but proportionally less: 4/5 Bound and 6/2 Rebound. This gave slower straight line speed, understeer when braking into corners and a nicely balanced oversteer on the throttle on corner exit (lift-off oversteer also). Put 6/6 Bound on. The nicely balanced oversteer ha diminished somewhat but has been replaced by a fraz of understeer that gives a sense of stability and actually allows faster exits. The braking understeer remains. Try exactly the same Damper settings as for the Vantage. Handles quite nicely and goes two tenths faster than before (BL 1:16.345). Try a more traditional 6/5 and 9/8 set-up. Slower by a couple of tenths, less grip mid-corner on fast bends, improved turn-in under braking, nice throttle-on exit lines. Try 5/6 & 9/8. Very good. The extra Bound at the rear, which should give more understeer, translates as extra grip allowing fuller use of the throttle. Try 5/6 & 8/9. Perhaps a bit better but it's very hard to tell but it 'feels' nicer to drive. The nonsensical 6/7 & 10/2 is still pretty fast but the last damper arrangement has it beat here.

Took her to a Family Cup race, at maximum difficulty and took a very easy huge win for 197 A-Spec Points (no Pro-Nippon bias there then :P).

Want to work on a theory that the 'Anti-Logic' Dampers can be turned back into proper function by correct balancing of the other chassis factors. Go back to the Vantage and get the stock chassis figures:

Springs: 9.6/8.4
Ride: 98/98
Damper Bound: 8/8
Damper Rebound: 8/8
Camber: 2.0/1.0
Toe: 0/0
Stabaliser: 5/5

Not badly handling at stock settings, the most obvious handling flaw being lift off understeer and a tendency to understeer on constant throttle. Lap times are slow at BL 1:14.3.

Weight Distribution seems to be 53.3/46.7 going by the static spring rate snapshot. Try altering the springs to 9.6/9.6 and moving the Weight Distribution Slider to -15. A feeling of improvement in the handling in that the lift-off understeer disappeared but the lap times did not improve. Try +15. Definitely more oversteer and the ability to use power-on oversteer more freely whilst power-off understeer has lost that 'jerk' to the outside that was evident before.
Increase the Spring Rates to 16.4/16.4. Handling now feels quite good and stable but the lap times do not improve and there is still understeer in the chassis. The Brakes at 1/5 help with corner entry turn-in but don't materially affect things on this circuit. Ah, HP has dropped again to 539. Go get an oil change HP=565. Re-run last test. 1:14.3's.

Lower Ride Height to 83/83. Instant improvment to 1:13.8's.

Stiffen stabalisers to 6/6. Feels tighter but loses traction at the rear a bit too much I think - doesn't affect the line but does lose exit speed. Try 6/5. Slower by quite a bit altho' the handling feels a lot nicer, less chance of messing it up. Try 5/6. Again, the lines feel very good but it's just not quite as fast. Try 6/7. Nope. The rear is too loose and yet there is a ceratin degree of understeer too in parts of fast corners. Stick to 5/5, it's defintiely faster.

The cars handling fine as it is but is two tenths slower than the Improbability Drive set-up I had before. Put the Bound to 6/6 and the Rebound to 9/9. Excellent! Got back into the 1:13.6's and even put in a 1:13.5. So, if you sort out the crippled chassis balance first then the dampers seem to work as you would expect them too - that's quiet a relief at the moment as I was beginning to worry myself with the outputs I was getting at the start of all this.

Now try the 'Heart of Gold' Settings on the Dampers: 6/7 & 10/2. Thankfully they're not faster, tho' they are as good and, to be honest, I find that the rear is much freer flowing with them; ah well :shrugs:.

I actually like that result as it suggests that there is more than one way to skin the tuning rabbit i.e. you can fix, to an extent, flawed chassis modelling by using more than one method.

Put her to the following:

Springs: 16.4/16.4
Ride: 83/83
Damper Bound: 6/7
Damper Rebound: 9/9
Camber: 2.0/1.0
Toe: 0/0
Stabaliser: 5/5

Test her out in a max. difficulty Family Cup race. Got a nice 194 Point victory.

Just to round this off, note that the above testing was quite exhaustive (it wsn't a case of change a setting, run a lap, reach a conclusion). I went through two chassis refreshes and a number of oil changes on the Vantage, so that's quite a few laps under the wheels :D.
 
Simply to complete the tale, here is the rest of my rough notes as I continued to fettle the Vantage (I know that it's not entirely releveant to the thread but it is illustrative of one way to go about changing settings and seeing what your testing reveals):

__________________________________________________________________

Want to look into the effects of springs and the LSD now. I'm currently running the Springs at 16.4/16.4, which is, not coincidentally, the cars weight divided by 100 at each end. The LSD is running at stock 10/40/20.

Try a 'traditional' approach and calculate the spring rates via a frequency of 1.0 for the Front and 1.1 for the Rear (altho' it should be 1.3 really). This, after a bit of maths, gives me 17.20 and 18.24. As the Spring Rate slider maxes out at 18, I can't apply those figures. So try 0.9 at the Front and 1.0 at the Rear - 13.93/15.07 (call it 13.9 and 15.1). You can tell that there is not enough roll resistance in the front and too much stiffness in the rear but the change allows more aggressive use of the brakes so that time lost due to power not being used to push the car forward is gained by the ability to brake more sharply (I get left behind by ... er ... me through Turns 1 and 2 but make it all up in the Turn 3/4 combination and then lose a little again in the rush to Turn 6 due to a slightly reduced exit velocity. Of course, I have the Weight Balance at +15 (slaps forhead!). Put that back to 0. Still not as fast, altho' the handling feels nicely 'loose' and is tolerant of too much throttle on exit (because the tyres let the energy out via slippage).

Try equal suspension frequencies at 1/1 (17.2/15.1). Much easier to drive in that you don't have to be so aware of your inputs but considerably slower than before. Ah, the chassis and the oil had gone off. That bodes well if the handling had been good with a dodgy chassis :D. After a few laps to adjust to the new feel, I was turning in 1:13.6's and 1:13.7's. Great. With a Damper set-up of an orthodox nature and a spring set-up of a very orthodox nature (allbeit derived from a slight disregard of traditional theory) then I could turn in laps just as fast as a 'weird' settings suite.

Try 'loading' the rear with the Ballast slider - add +12. Definitely more 'push' from the distribution change giving more understeer on exit. This could mean either that there is extra weight on the rear giving more grip or more weight on the front overloading the tyres. A possible alternative read on the Weight slider is that it is geared towards altering the relative weight of the front to the rear (hence the label on the slider of "Front/Rear Balance"). So +15 may mean something akin to 15% more weight on the nose, thus causing 'wash' understeer. Try -12, which may mean 12% less weight on the nose and hopefully will mean better traction to the drive wheels whilst allowing the front tyres to grip and turn properly. Turned in a 1:13.5 but the rest of the laps were marred by pushing too hard trying to get a 1:13.4 :embarrassed:. The handling is nice in terms of pointability but you have to watch the loud pedal as it easy to press too hard and lose time when the fronts can grip and point so well. Try halving the difference i.e. -6. Same story; the handling feels so good and the nose so pointable that you push it and push it until it lets go and you make a mess of a corner and end up with a slower lap because the rears spin up and touch off the TCS. Weight balance at zero once more for comparison. About the same laptimes occur as before as I'm now locked into Ghost Chasing rather than Test Driving Mode :(. I prefer how she feels with -6 on the Weight Balance so I'll put it back on.

Time for the LSD. A big drag on lap times is that I have to brake so much for Turn 1 or I run off into the outside Armco. Also, with too much throttle the rears are losing traction as I gun it out of corners. The latter does mean that the rear comes around but it also means that I'm losing acceleration. First, see how tweaking the Accel value affects Turn 1. Try 60. The benefit in acceleration is obvious and the handling penalties for turn-in don't seem too bad ... until you mess up an entrance slightly, then you notice the understeer as your line to the exit gets wider.

I don't find the corner entry to be particularly prone to understeer badness but I'll try reducing the LSD Decel to 15. I might be imagining things as I'm pushing hard tonight but I thing that increased the exit understeer problem. Try Decel 30. Very marked improvement in lap time (BL 1:13.347) - subsequent drop in lap times again as I keep on pushing too hard (racing the Ghost rather than racing the track).

As an experiment, raise the Initial to 55 (the torque value of the Vantage in ft/lb. First lap is good and then subsequent laps decline - a familiar pattern tonight and I don't think I'm making much real progress. The car is very stabalised through Turn 1 and I can take more liberties there but if I'm not rough enough with the throttle I get understeer in other places. Try 55/55/55. Awful. 55/40/20. Rubbish. 55/60/30. Nope - oil needs changing. Try again - BL has dropped markedly. Try 10/60/30. Can't replicate the previous results. Try 10/56/28. Okay but laps are still not better than 1:13.5. Give up for tonight as I think driver fatigue is intefering with testing.

Back to the track after a couple of days off. Running:

Springs: 17.2/15.1
Ride: 83/83
Damper Bound: 6/7
Damper Rebound: 9/9
Camber: 2.0/1.0
Toe: 0/0
Stabaliser: 5/5

Weight Distribution: -6

LSD 10/40/20

Have a nicely handling car that does mid 1:13's at High Speed Ring. There is a little too much understeer for my taste in the pre-apex phases of the corners in that I have to wait longer than I want to to get on the throttle but still not a big problem. Try stiffening the Stabalisers to 6/6 and see if that helps. Not really. There is a tendency to understeer going into the corners and a tendency for the rears to spin off power on exit again (altho' mid corner stability is good). Lap times remain the same, it's just the feel of the car is more 'brittle' and I prefer it as it was before. 6/5 is consistently two tenths slower and you can feel the resistance to turn-in quite markedly. Try 4/5 to see if the reverse holds true. It does and the throttle-on oversteer response is nice ... but the four tenths drop in lap times isn't. Put stabalisers back to 5/5.

As the biggest problem is mid-corner/pre-apex understeer, try reducing the LSD Initial to 8. No improvements to lap times but a much 'easier' feel to the car. Increase Accel to 48 and Decel to 24. Not sure if I like it. There is more control on tap for exits and these are faster but the lift-off understeer twitch is back after a long abscence. Drop Decel to 16. Feels freer again but it still is no faster, I like the handling tho' so leave the LSD at 8/48/16.

I've been running a default gearbox for all of these experiments and it never gets out of fifth gear. Try shortening the box and see what gains that gives me and if any handling changes occur. Default is AutoSet 13. Shorten it to 8 - good guess as that's bang on the red-band in 6th at the fastest parts of the course. Lap times are dreadful; half a second slower at times. Try the Tranny Trick (6th is currently 0.748 and the Final is 3.540). That gives a 6th Gear of 0.757. Try a Final of 4.000. About the right length but the car is still a tenth slower because it appears to lack torque in 6th. The handling is very flowing, however. Try lengthening the Final so as to fully use only the first five gears and see how the handling changes. Still slow and bad on-power understeer. The general feel of the car is much improved by Tranny Trick and Final of 4.000 and I reckon I can sacrifice that small time lost for a car that's more fun to drive (altho' I do miss the 'cruise' ability of that long, default box :D).

For this circuit, I have the Vantage behaving quite pleasantly. I think that the Brake Bias could be shifted even further rearwards than the 1/5 I'm running at the moment but it suffices on the High Speed Ring. Other courses may have different requirements :).

________________________________________________________________________

Here's hoping that all that is of use to someone - even if it's only someone looking for a suite of Vantage settings :D.
 
Back