Ruf's and Tire Physics?

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speedrcr
First off I love the game and it's improvements! I'm really happy with some of the physics and the improvements in general with the game and my hat is off to you guys that worked on the game.

I want to also say a big thank you for updating the Ruf models, they are fantastic and very good looking at that! Also the Tire physics in most cars seem very accurate in the few cars I have driven in real life that were on DOT sport tires with a medium compound on a few track days. Very spot on I must say!

However, here's not necessarily the bad stuff, but maybe room for improvement.

To start, lets start with the things dear to my heart, (the closest I can get to a 911 in the game) Ruf's.

As I stated before the RGT, BTR, and CTR models are gorgeous, yet a few inaccuracies with proportions and realism I feel.

The RGT is off in the sense if you look at the rear wheels, the dimension of the track width is off! Not slightly where its a minor annoyance, its GREATLY off.

Take for instance the picture of the real thing:

rufrgt.jpg


Notice in the picture above the wheels are set slightly further outward in the fender well in comparison to the game. Well in the model notice how both the front and rear wheels are set in the fender well too deep and are not flush with the body? This became even more apparent when changing wheels as you can really tell the tires are set way too far in the wheel well.

Look at the following image and tell me there isn't something off about it:

11330084353_2fa8570a78_b.jpg


Below is with Plus 1 Wheels and their position needs an "offset" greatly as well.

11330084153_d7865c894e_b.jpg


The truth is in the details, and if you look closely you will see the front wheel track width seems wider then the rear (or at least something looks a little off).

This is also true with the BTR, using same size as stock or +1 or +2 inch sizes. The rear tires look as if they are skinny in comparison to the real thing. Other cars with about the same width of tire look proportionally correct where as the Ruf's are sadly over looked. Using the image above, does it look like the RGT from GT6 has those wide of rear's? No, they look about 10% smaller at least and the rear axle is shortened.


With this and the naughty physics of the car, I wonder if perhaps the model is off and calculated improperly for it's handling physics.

I also noticed that the Ruf's have better handling characteristics with Sport Soft Tires, but as soon as you put Racing Soft's on the rear becomes unstable and with long benders on Nurburgring, the tires become overheated too quickly to where I've spent hours with the suspension trying to alleviate the issue with no end in sight. Granted with a little LSD adjustments it's helped but still same issues on long fast turns that other cars don't have an issue with namely the Tesla S.

I've tried adding weight to a Stage 3 reduction from adding more weight in the front, to adding more weight in back.

Same issues.

My request is simple, adjust the model for accuracy and possibly the physics that come from this will sort itself out. I'm all about the artist representation of a real life model, but sometimes that can be slightly distorted with missing certain details.

PD if you are reading these I'd ask you to make some adjustments with upcoming patches.
 
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I took some shots to try to line up best in what one would say "eye'ing it". But you can see where its off obviously?!?

PD please fix if you see this :) Should be a simple fix in the model in widening the rear axle.

I edited the original post to reflect the changes.


Here's some more porn for your pleasure though:




11329628685_cebdf5896b_b.jpg


11329732924_95238239ca_b.jpg
 
Trying to find a colour similar to Cobalt used on the 996.2 GT3 , and those are the closest wheels I could find.

See you like them on your RGTs too 👍
 
PD always seem to overplay the rear weight bias on Porsche.

I tried the RGT in a career race at Ascari a couple of nights ago. The car is stock except for the suspension and wheels, and even on SS tyres (specified for the event) it was incredibly unstable at the rear. Any attempt to carry even a fraction too much speed in to a corner resulted in the rear swinging round, and once it started to slide, it was VERY difficult to catch.

I didn’t mind it too much as it was a good challenge to keep the car pointing straight ahead, but it didn’t feel very realistic – I don’t own an RGT, but I do own a 996 C2, and that’s nowhere near as unstable even running normal road tyres (I have P Zeros on mine at the moment, but have also run Conti C2’s)… my car predominantly understeers on the way in to a corner unless you trail brake, the RGT oversteer if you so much think of braking whilst turning!

I was having to drag the throttle whilst braking to control the rear end.
 
I didn’t mind it too much as it was a good challenge to keep the car pointing straight ahead, but it didn’t feel very realistic – I don’t own an RGT, but I do own a 996 C2, and that’s nowhere near as unstable even running normal road tyres (I have P Zeros on mine at the moment, but have also run Conti C2’s)… my car predominantly understeers on the way in to a corner unless you trail brake, the RGT oversteer if you so much think of braking whilst turning!

I was having to drag the throttle whilst braking to control the rear end.
Exactly, trail braking is key to get some kind oversteer, but you can't do that properly in GT6 now.

I went with a friend to a media event here at the Circuit of Americas where they had a Track Day event (mainly for media and a few others) and they had a 997 GT3 RS that I rode around in (didn't get to drive). The car was on Michelin Pilot Super Sports (comparable to sport softs in game I guess) and it took corners and and long benders at high rate of speed less any instability. Didn't seem the rear wanted to step out any and was very very stable and fast. Granted there might be a drastic difference to a 2000 GT3, where as the RGT is based on, but the performance won't be as bad as it is in game I figure.

I've seen a few mkII 996 GT3's at the track in my day and they perform a lot better then what's in the game.

I also had quite some experience with GTR 2 in setting up GT3's (as there was a million of them 2003-2004). I played the game as my online fix of racing from 2005-2009, so I have quite a lot of experience with setting up porsche's in games. Once you figure out the translation in physics it's easy from there.

I've been playing around with my geometry a bit (suspension) and taking some advice from a friend at a performance shop who does alignment and setups for track cars, namely 911's.

Unfortunately its tough to setup a car compared to real life as you don't have the computer doing alignment and calculations, along with experience and intuition. Seems the advice I was given would cause too much instability.

My buddies reply when I would tell him it didn't work: "Your damn game is broken".

LOL

I don't think the game is broken, maybe I need to tweak more again and again to find that sweet spot, but I think if the model was updated that might have some gain in performance.


I'm just mainly concerned that the tires and physics don't seem accurate as far as the 911. I'm able to get the Tesla S to hand better than the RGT using my buddies advice...how is that? I had the same complaint in GT5 but I figured out eventually a solid setup. I don't think this is the case with GT6 however.
 
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Would any RUF fanatics have a tune for the BTR by any chance? At the moment mine is bang on 500PP with SH tyres.
 
I hate to hear this news. I was a Porsche mechanic back in the early '80s. My next purchase was going to be a RGT since it was my favorite car in GT5. Now that I have seen these pictures and hear about the handling issues this just pushes my disappointment with GT6 even further.
 
I hate to hear this news. I was a Porsche mechanic back in the early '80s. My next purchase was going to be a RGT since it was my favorite car in GT5. Now that I have seen these pictures and hear about the handling issues this just pushes my disappointment with GT6 even further.
So many of you are complaining when some car handles bad. My CTR handles really well, as along as you brake in a straight, don't lift mid corner, and have smooth steering a throttle inputs. Instead of bashing the game, take a look at how your driving the car, and make adjustments.
 
So many of you are complaining when some car handles bad. My CTR handles really well, as along as you brake in a straight, don't lift mid corner, and have smooth steering a throttle inputs. Instead of bashing the game, take a look at how your driving the car, and make adjustments.

Liam, I know how to drive a 911. I spent 5 days a week for almost 3 years driving them on and off the track. I spent many at track day at Charlotte Motor Speedway. How many miles have you driven a real 911? I'm not having any issues with the cars I have except for the horrid tire noise. My comment was more about the pictures with the rear track seeming to be more narrow than the front. My opinion about GT6 is my opinion. You have yours and I have not made any comment on any of your posts. I would appreciate it if you would leave my comments alone.
 
So many of you are complaining when some car handles bad. My CTR handles really well, as along as you brake in a straight, don't lift mid corner, and have smooth steering a throttle inputs. Instead of bashing the game, take a look at how your driving the car, and make adjustments.

Try reading the posts before you start bashing the posters ;)

I've had every version of GT, I'm an ex GT Academy UK finalist and regularly ranked top 30 in GT5 Seasonal TT's. And I have driven over 80,000 miles in a Porsche 992 C2 over the past 6 years. Your experience is what?

If you took the time to read the thread, you would notice that we are discussing the RGT, not the CTR. The RGT is 2 generations later than the CTR. You have to trail brake to drive a 996 quickly or it understeers. The CTR should be the one with loads of turn in oversteer.
 
PD always seem to overplay the rear weight bias on Porsche.

I tried the RGT in a career race at Ascari a couple of nights ago. The car is stock except for the suspension and wheels, and even on SS tyres (specified for the event) it was incredibly unstable at the rear. Any attempt to carry even a fraction too much speed in to a corner resulted in the rear swinging round, and once it started to slide, it was VERY difficult to catch.

I didn’t mind it too much as it was a good challenge to keep the car pointing straight ahead, but it didn’t feel very realistic – I don’t own an RGT, but I do own a 996 C2, and that’s nowhere near as unstable even running normal road tyres (I have P Zeros on mine at the moment, but have also run Conti C2’s)… my car predominantly understeers on the way in to a corner unless you trail brake, the RGT oversteer if you so much think of braking whilst turning!

I was having to drag the throttle whilst braking to control the rear end.
I have to get the RGT out again this weekend. I took it out for 3 laps when shutting down the game a couple of nights ago, worried it was torpedoed by the same physics ailments other MR/RR's are suffering from. I was pleasantly surprised it seemed to be unaffected. Maybe it was the sleep deprivation that got to me...lol. I can do without a Cizeta or Diablo, but I can't do without my RGT!!

So many of you are complaining when some car handles bad. My CTR handles really well, as along as you brake in a straight, don't lift mid corner, and have smooth steering a throttle inputs. Instead of bashing the game, take a look at how your driving the car, and make adjustments.
Sorry you got annhilated Liam:cheers:..but are you saying that the CTR2 doesn't plow like a bulldozer any more because I found it awful in GT5. If so, that is great news indeed!!!
 
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This might just be me, but I just did some testing on the RGT and I think that changing the wheels affects the rear grip.

I wondered if something I'd done to the RGT made it handle poorly when I tried it, so I bought a brand new RGT (painted Rubystone, my favourite 964RS colour :D), and took it to Suzuka East in single player TT - Suzuka East is a good testing circuit as it has the tricky fast entry trail brake in to Turn 1/2, numerous changes of direction, it's nice and short so you get plenty of laps in to run consistently, plus I know it really well.

Started with bone stock car... felt nice. I could use the weight transfer to line the car up without it feeling at all snappy, though braking in to turn 1 form high speed was tricky
Changed to sports soft tyres... felt the same, but faster
Added cust suspension and lowered the car... no major change
Added camber (1.0f, 2.0r - fairly conservative for a real life 996 track set up as most people use over 2*f)... no major change
Added fully custom diff and set to stock settings (7,30,15)... not major change

Saved my ghost, exited, added +2" OZ racing rims, re-entered and reloaded the ghost

Car felt much more loose under braking in to turn 1/2 and once it started to slide it snapped violently back. Persevered, but struggled to complete a lap.

Fitted +1" rims, felt equally as bad.

Went back to stock, felt good again and could match my ghost.

Tried a different design of wheel at +1" and felt bad again.

Would be good if someone else could test this and tell me if it's just in my mind!!
 
As for the handling of Ruf's (ie. Porsches) in the game...

911's have a high polar moment of intertia. Their engine is stuck way out back, outside the rear axle-line. Therefore they tend to produce snap oversteer mid corner, especially while not under weight load. Which is loosly and ultimately inaccurately reflected in GT6 due to the severity of this they have programmed in. These things are undrivable. The 911 is the most decorated sportscar racer of all time and although it has its handling quirks, it didn't come on the back of impossible handling. It's rather unforunate that I bought a nice robin's egg blue BTR only to find that its best performance is while sitting stationary under the lights in my garage.

I've always found that the mid engined cars in the game also exhibit quirky handling (all the way back to the start of the franchise). I've always been puzzled by this, as a mid engine is the opposite (low polar moment), and one would expect they'd possess very balanced handling. Stratos, NSX, Elise, Special Clio, MR2, etc. all behave otherwise. They're constantly demonstrating unpredictable tendencies.
 
I haven't driven the BTR yet, but the RGT is lovely stock.

A 911 has a very LOW polar moment of inertia - even lower than a mid engined car.

A front engined car has a high polar moment of inertia - something like an Audi, with the engine ahead of the front axle would have a very high polar moment of inrtia.
 
I'll have to try one out. Rufs have always seemed a little too difficult to drive in previous games(this is an assumption as I've never driven one in rl) and the cars I have driven in the game definitely seem to require smoother, more precise inputs than in GT5. So I can imagine the Rufs now being undriveable. Unfortunate since these cars really cool.
 
I haven't driven the BTR yet, but the RGT is lovely stock.

A 911 has a very LOW polar moment of inertia - even lower than a mid engined car.

A front engined car has a high polar moment of inertia - something like an Audi, with the engine ahead of the front axle would have a very high polar moment of inrtia.

A car with the mass towards the center (mid engine) is going to have LPM because there's less weight on the extremeties.
You state that a front engined car would have HPM, but why would a rear engined car not also then be HPM? The back end of the car is bound by the same physics as the front end.

Here's some reading material that may assist you:
http://www.caranddriver.com/feature...ne-debate-porsche-cayman-r-vs-911-gt3-feature
 
Would be good if someone else could test this and tell me if it's just in my mind!!

I tried to apply my old GT5 replica tunes for a 996 GT3 on the RGT.
https://www.gtplanet.net/forum/thre...miya-devil-rise-7.217038/page-10#post-7106823
Was quite surprised that I was not able to feel a big difference between stock setup and my modifications.
Somehow I had a bigger expectation in the face of the improved physics model of GT6.
Will try different wheel sizes too and report my experience...
 
When we put +rims to 430 scuderia with my mate, it immediately became snappy at the back. weird :)
 
I daily-drive (really daily drive - 4-season, having tons of fun in the snow right now…) Porsches of the same basic era as the BTR and YellowBird (chassis essentially identical). I have also driven RR cars my entire life (starting with Beetles) and now have 7+ seasons of Autocross and Ice-X in classic RR Porsche and Beetles. I don't have any track experience, but I can honestly say that I am *very* good at autocross, having won my club's annual Speed Champion position twice. My club also includes a former national H-Stock champion, who I usually beat in raw-times even when his car outclasses mine. Although admittedly he is probably 65 years old now and won that championship in the 1980s or so. I also do enduro kart racing whenever possible. Basically, I'm incredibly comfortable with RR cars, and am one of those Porsche drivers who firmly believes the engine is exactly where it should be. I drive them very much as they should be driven, using the throttle to rotate the car as much as I do the steering. To say that I'm fond of, and utilize, lift-off-oversteer would be an understatement. I prefer a car which begins to rotate aggressively but controllably when I lift my right foot, and then transitions back to manageable understeer under throttle. I can pretty much play "lift-rotate-countersteer-squeeze-go" all day long. I'm going to go ahead and toot my own horn a bit here and

In GT4 PD had things almost exactly perfect in terms of their RR handling dynamics. Transitioning from a real-life 1980 911SC (German import - around 200hp) to the RUF BTR was incredibly easy, needing only more gentle throttle input in GT4 due to the massive amount of additional power. Let off the gas: manageable oversteer unless you screwed up badly. Squeeze back on the trigger: transition back to understeer unless you mashed the pedal too hard. VERY VERY close to the real car. In GT5 I can't even begin to tell you how bad they got it - simply totally and completely wrong. It wasn't even possible to drive the Yellowbird around large sweepers at a normal "daily driver" pace without the car suddenly and unexpectedly going nuts. They "screwed the pooch" big-time on that one, so I was very worried about GT6.

So now on to GT6, where I've only driven the BTR (completely stock) in a handful of races. Things seem somewhat close again to correct, but I haven't really driven it enough to know for sure. I definitely have a harder time than I should getting the rear to "settle" once I let it step out a little, but it's not too bad so far and I need to do a lot more testing before I make a judgement on this. The one thing that's really distressing, however, is the excessive "snap-back" I'm getting. I'm perfectly aware this can happen in real life, but it has never once happened to me, even in relatively high-speed and/or extreme oversteer conditions. In GT6 it happens nearly every time I try to let the rear of a car step-out, so I feel something is probably not quite correct here. I think maybe PD is trying to "force" the RR (and MR) "pendulum" effect to show people what *can* happen, but have possibly implemented it far too aggressively.

I will be tuning my BTR soon to emulate the actual Porsche 911SC that I race (not my daily-driver, that is a '76). I'll drop the power down, increase the weight if necessary, etc, and then see if it handles like the 911 in real-life. That should give me a better idea exactly how well PD has managed the RR physics in this iteration of Gran Turismo.
 
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Hi! I'm a RUF enhusias, virtual one.
Just here to mention the two cases I noticed: aftermarket wheels are narrower than the default ones.
This happened:
Viper GTS Launch Edition '13 which has only +1 inch option --> back tyres narrowed clearly
Cizeta V16T with +2 inch option -- the back tyres narrowed hell of too much, looked really pitiful and unphotographig.
Haven't tested the effects yet..
 
The RUF RGT is by far the worst car I've driven in GT6 so far, so much so that I sold it after 3 races. It should've had plenty of traction in the rear but instead it kept spinning out without warning...
 
The RUF RGT is by far the worst car I've driven in GT6 so far, so much so that I sold it after 3 races. It should've had plenty of traction in the rear but instead it kept spinning out without warning...

Did you change the rims before you tried it?
 
Could there be aftermarket inch up wheel glitch on certain cars ? I replaced the wheel on both new replicas I made - Nissan S14 Zenki Kei Office 260PS and AE86 Levin GT Apex Nishizao SPL 160PS, tried stock wheel, and then aftermarket wheel, no drastic changes on the rear behavior, same tune - both on comfort medium ( YH GP M7 tire ). I think the steering response is a bit different and a slight difference in acceleration :) Drove both at Willow Springs and great joy to drive for hot lap and drift.
 
I do have a theory, and although I trust my own ability to feel differences, I'm not confident enough to start a thread in the main forum until I get some 2nd opinions from other known fast/consistent drivers.

It felt to me that adding new rims didn't replicate the wider rear tyres on the RUF - real car has 225f 285r, and it felt like changing the rims in effect gave me 225f 225r.

I haven't tested on anything other than the RUF, but given how some people are saying a number of MR cars are undrivable and others are saying they are fine I wonder if there's more to this.
 
I do have a theory, and although I trust my own ability to feel differences, I'm not confident enough to start a thread in the main forum until I get some 2nd opinions from other known fast/consistent drivers.

It felt to me that adding new rims didn't replicate the wider rear tyres on the RUF - real car has 225f 285r, and it felt like changing the rims in effect gave me 225f 225r.

I haven't tested on anything other than the RUF, but given how some people are saying a number of MR cars are undrivable and others are saying they are fine I wonder if there's more to this.

Gemasolar.jpg
Gemasolar_1.jpg


Seems to do that with MP4-12C, 458 Italia etc, too.

And yeah, changing the wheels definitely changes the handling too, no doubt about it. Lots of oversteer :crazy:
 
And yeah, changing the wheels definitely changes the handling too, no doubt about it. Lots of oversteer :crazy:

Good to see you're still around, Sutuki 👍

The pictures are obvious (definitely looks like changing the rims visually changes the width of the rears), but if the effect of new wheels was purely cosmetic it wouldn't make any difference... it's reassuring that other think it effects grip too.

Thanks for making me feel less like it's just me going mad!
 
And yeah, changing the wheels definitely changes the handling too, no doubt about it. Lots of oversteer :crazy:

Great find! Pictures also proves that the wheels are in a negative offset as well!

I did a little snooping around on the internet trying to get some proper wheel sizes and track width.

Front track:1476 mm / 58.1 in
Rear track:1496 mm / 58.9 in


Front tires:225/35ZR19
Rear tires:315/25ZR19


(source:http://www.carsession.com/car-specs/2000-ruf-rgt.html)

When you look at the details of the car they state 285 as the width of rear tires in the game. Well that was for a standard wheel option on a Mk I 996 GT3. The tire width for an RGT is actually 225 in the front, and 315 in the rear! (I feel cheated in GT5 now..lol)

Now this is another reason "feel less like it's just us going mad"!

Now I'm not sure how much PD pays attention to this forum, but I'm inclined to submit these issues where they can be taken care of properly.
 
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