How have you tuned the gt40?

Howdy!

I find the GT40 with the default setup very unstable. The back end steps out--oversteers--all the time. Under power isn't too difficult to control. It's really a struggle to control off throttle oversteer and braking oversteer.

Here's what I have tried:

Reduced rear tire pressure a few PSI.

Increased rear bump from 2 to 3.
Decreased rear rebound from 3 to 2.

Decreased rear ARB from 6 to 2.

Set front wheels to toe in about .05.

Set rear wheels to toe in about .07-.10 (default 0)

Increased rear negative camber a few clicks.

Moving brake bias forward.

I might have tried increasing front bump and rebound but I cannot remember. Now that I think about it more it could certainly be a case of significant longitudinal & diagonal load transfer.

All of these things helped but it still didn't feel "good" to me. I couldn't get in the zone and get consistent.

Has anyone been able to tune this to their liking?

@Tberg
@Richard Dastardly
@LilSki
@norbs
@Animal Ed
@Lankyleo
@flyingpig
@aphidgod
@esox71
@PuffTheMagicBelgian

 

Not really messed much - rear ARB to 1 for Bridgehampton, might have tweaked the dampers a little also, but I don't mind a snappy rear that much.

 

Reducing the rear ARB seems to improve traction on the rear, particularly at bumpy tracks like the Nordschleife.

 

Can somebody explain me why fuel tank is at front ? Everybody just ignores me with this question.

Off throttle and braking oversteer are very much related to engine braking torque. Preload and coast settings, engine coast linear curve. I have spined out at heavy braking points a few times going from 3rd to 2nd gear or especially from 2nd to 1st. You have to be be respectful to revs when downshifting. Aphidgod explained me how it works, and it is very simple. It is engine braking, which means that for rwd car rear wheels are braking. When torque is too high effect might be simmilar to handbrake

I have never messed very much with setup of GT40. Everytime I decrease tire pressure, increase front camber, increase rear diff. Oh diff is now not adjustable. That car is very well controlled by the pedals, a little brush on brakes would give desired weight transfer for front, slightly harder step on throttle would spin car a little then even harder push on throttle to pull it out of the slide and you can be quick through corners. GT40 seems very stable for me.

 

I don't actually know, but I'd guess it's there because the engine takes most of the space at the back. And it's quite small car.

 

Fuel tankS goes like this

 

Interesting design. I had no idea.
I see two reasons why it's like that, keeping the weight as low as possible, and also the weight distribution of the car stays the same despite the amount of fuel in tank.

 

Makes sense. I might try taking the brake bias even more forward. I probably need to be mashing the throttle a lot deeper when downshifting, and possibly throwing it in neutral during initial braking.

It may be a case of steering wheel size. There are certain I cars I have big trouble with controlling and they feel twitchy-GT40, Shelby Cobra. The common denominator is that the car steering wheel is very large--even though my G27 wheel can match the actual 900 degrees of wheel rotation the G27 wheel itself is like half the size of the real wheel, causing the car to feel very twitchy. Wheel adapter will be installed after Christmas.

Additionally, it's surprising that no one has ever talked about wheel sizes of the cars in sim and how it affects handling. It would really make sense if we could input our actual wheel size. This way the game could change rotation ratio from 1 to 1. For example, your wheel is 900 degrees, but the size is 11 inches (g27). The car you are driving has a steering wheel size of 35 inches. Game does the math to figure out the correct ratio. If this were done, of course it would end up using gamma as well since your 900 degrees of wheel rotation equates to less than 900 now, so you would have to use gamma to get the last couple hundred degrees of rotation or so.

In addition, I use a gamma of about 1.13 on cars with rotation over 900-- RUF, Countach etc. Without it it is a bonkers twitch fest.

 

If these are the fuel tanks ... I'm not sure how good that idea is ...

 

Interesting how the fueltanks are designed and where they are situated. Not exactly a 5 star EuroNCAP rating I think, but same goes for older F1 cars

Cheers
Robin

 

Are you talking about wheel rotation or pedals?

 

Ain't nobody got time for that. Especially when you want to kick Ferrari's ***.

 

I might try to give some generic advice but not sure would that be helpful.

Reason is that I don`t like GT40 at all because it feels way too much modern.
The most annoying is the engine. Throttle response like it have engine management, without any hesitation, revving up to 8000 rpm despite having 2 big valves per cylinder and only one camshaft in engine block (!) so valves are bouncing and floating no matter how stiff springs you have irl ... unless this is not vintage racer, it is vintage race legal car - big difference.

Rant mod off (click)

Brake in straight line, avoid trail braking because you need to be slightly on throttle before apex to solve your second problem (lift off oversteer) and be able to use this car characteristic as advantage (throttle steering) ... also, if you have H shifter - skip gears on long braking.
I use to do that but pattern can depend on corner.
Sometimes it is 5th, 4th, 2nd or 5th 3rd, 2nd and extremely rare is direct from 5th to 2nd right before releasing brake and turn in ...

Considering cambers and tires - dunno what to say because it have cross ply tires (soft sidewalls) so pressure should be relatively high comparing to modern tires but v5 model is still a mess so heating, pressures, slip angles and ratios are confusing at the moment - at least for me so I`m taking little sabbatical because it is not fun for me to drive car which responds illogically on setup changes.

 

Rotation.

Thanks Animal Ed. Really good info! I did realize with some time that it only liked to brake in a straight line, but hoped I could tune it so that it could trail brake etc.

Also, thanks for the rant as well. Very interesting. Sounds like a new post is warranted on that.

 

Yeah, imagine drive this:

http://www.coastal181.com/buttons-12-3j/425-Jim-Clark,-Cruel-Sport.jpg

Is the fuel tanks on side of his legs?

 

You can still trail brake gently, but don't mix it with the engine in high revs - and there is some tendancy to understeer if you do anyway as you might expect. Usually though the engine braking is enough by that point, you don't have a massive grip circle to work with.

 

Sorry @Seria17hri11er I am the last one to ask about car setups

 

I'm going to tag you in all my future car setup threads to learn you somethin!

 

What I do know.

less fuel equals faster, but less laps.

 

if you want to race it at monza66 then id say go full throttle around the middle sector against the walls, based on RSR