- 7,527
- Exorcet
- OE Exorcet
The problem is, basically all 1000 cars behave the same. They have a static grip value.
Tire Testing - Strange, but interesting results...
- Thread starter calan_svc
- 261 comments
- 58,825 views
The problem is, basically all 1000 cars behave the same. They have a static grip value.
- 36
- sparrow_ger
Very interesting thread!
Even before reading it, I was disappointed by GT5's simple and non-transparent tire system. I figured that there are no "comfort" and "sport" tires, but just 9 tires with different grip levels (CH = grip level 1; RS = grip level 9). And that things like tire width aren't considered at all. No matter what car you install a grip level 5 tire to, they all will have the same resulting grip.
As it seems, I was right (unfortunately). But there is one exception:
If you read tests/reports about semi-slick tires (= sport tires), you usually read warnings about the poor performance of those tires compared to "normal" tires (= comfort tires) under wet conditions.
I wanted to know how GT5 handles this, so I compared CS and SH in rain. I used the track editor to create an eifel track with rain. I set the behavior on wet tracks to "realistic" (very important!). While I was able to finish the lap in 1:40 on CS, it took me more than 1:50 on SH. Even on SS I was not able to beet my CS lap time!
So there actually IS a difference between comfort and sport tires in GT5 (aside from the grip values). At least under wet conditions. After all the disappointment about the tire system, I was happy to see that at least the weakness of semi-slicks on wet streets (compared to normal tires) was implemented into GT5's engine.
Even before reading it, I was disappointed by GT5's simple and non-transparent tire system. I figured that there are no "comfort" and "sport" tires, but just 9 tires with different grip levels (CH = grip level 1; RS = grip level 9). And that things like tire width aren't considered at all. No matter what car you install a grip level 5 tire to, they all will have the same resulting grip.
As it seems, I was right (unfortunately). But there is one exception:
If you read tests/reports about semi-slick tires (= sport tires), you usually read warnings about the poor performance of those tires compared to "normal" tires (= comfort tires) under wet conditions.
I wanted to know how GT5 handles this, so I compared CS and SH in rain. I used the track editor to create an eifel track with rain. I set the behavior on wet tracks to "realistic" (very important!). While I was able to finish the lap in 1:40 on CS, it took me more than 1:50 on SH. Even on SS I was not able to beet my CS lap time!
So there actually IS a difference between comfort and sport tires in GT5 (aside from the grip values). At least under wet conditions. After all the disappointment about the tire system, I was happy to see that at least the weakness of semi-slicks on wet streets (compared to normal tires) was implemented into GT5's engine.
- 1,233
- Patra
- Rotorist
Exactly! I have seen that too! Very nice implementation of wet grip there.
As for tire deformation not been there, I agree that maybe it's the reason for not realistic grip levels of different tires in GT5 but: I support the view that the actual difference in grip level between different vehicles with same tires doesn't actually appear when doing constant circles at 50kph but when squeezing them around a track on the edge. Then you can compare the level of grip in same corners. The balance of the chassis in conjunction with the weight and the suspension settings and the aero appear under high pressure. There, the ability of a vehicle is definitely judged.
A car magazine here in Greece compared 10 or more sports vehicles 7 years before and found out that on Serres circuit, Mazda RX8 had a max grip level of 1,18G - same as Lancer Evo8 MR (EU model). What tire must put on it in GT5 then? RH maybe? No, because if you take it for a ride with SH or SM on it, there are some fast corners that may reach this level for some tens of a second. So?
mykem
Premium
- 1,260
The RX-8 must have been on a slick/race tires because it would be impossible for any stock/OEM tires to produce that kind of grip. Just for comparison, the latest Corvette Z06 with the new optional Michelin Pilot Sport Cup ZP (Zero Pressure) semi-slick records a 1.13g on a skid pad test.
The best source for skidpad (and therefore maximum cornering grip) test is Road and Track. It's best because they've standardized the test since the 1970s. (Especially if you use this source as to all your calculation)
The number for the Mazda RX-8 is actually .88g. If you use Calan-SVC stock tire calculator, the right tire option is Comfort Soft (CS).
Edit- The actual OEM tire for the 2007 RX-8 Sport is the Bridgestone Potenza RE040. In term of grip and performance, it's less than both the RE-11 (semi-slick), RE070 (stock on some Nissan R35 GTR) and RE050 (OEM tires for Ferrari Enzo as well as the BMW Z4M).
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shirakawaa
Premium
- 5,034
- GTP_shirakawaa
Anyway, since there's a definite difference between Comfort and Sports tires on wet roads, regardless of real life skidpad performance, as I've written previously, I wouldn't use sports tires on a car that is supposed to have treaded summer tires in RL. For example, in GT5 mid-high end Mercedes cars come equipped with Sports Tires. However in RL they usually have performance summer tires, not semi-slick tires. There are many similar examples in GT5 especially among Standard cars.
I don't think we should use tires that give the closest skidpad G values to the actual ones, but those that are supposed, in a logical manner, to represent their counterparts in RL.
In GT5 after all for each category there only are 3 compounds and 1 "manufacturer" (let's call it "PDI Tires"). In RL skidpad performance might differ noticeably depending even just on the tire manufacturer.
I don't think we should use tires that give the closest skidpad G values to the actual ones, but those that are supposed, in a logical manner, to represent their counterparts in RL.
In GT5 after all for each category there only are 3 compounds and 1 "manufacturer" (let's call it "PDI Tires"). In RL skidpad performance might differ noticeably depending even just on the tire manufacturer.
- 36
- sparrow_ger
I guess when you do max grip level testing on circuits, downforce will influence the result. The higher the speed, the higher the downforce created by the cars geometry (incl. spoilers etc.). To be able to compare grip level measurements, you have to make sure to use the exact same test parameters. The speed in the skidpad test is much lower than on a curcuit.
Since there is only a small influence by the aerodynamics in the skidpad test, it is better to use the results of this test when you want to evaluate tires (compared to results from curcuits).
mykem
Premium
- 1,260
I don't think Sport Hard in GT5 (the usual tires for performance Mercedes in the game) is supposed to represent semi-slick/Competition DOT eg. Bridgestone Potenza RE-11, Michelin Pilot Sport Cup or Yokohama ADVAN A048 but instead tires like the Michelin Pilot Sport PS2, Bridgestone Potenza RE050 or Pirelli regular PZero (not Corsa) which are all Max Performance Summer tires.
Sport Soft are tires the best represent semi-slick/competition DOT while Sport Medium probably sits between the performance of semi-slick and that of Extreme Performance Summer tires eg. Potenza RE070, ADVAN AD07/08.
The good thing about Calan_SVC calculator is that it takes some guesswork out of the equation- it's not infallible but use it as part of a more thorough research, it's invaluable. As I've mentioned before in GT5 Prologue, PD gave us a list of equivalent tires for real world performance although it was in no way perfect, it gives someone like me, a good approximation.
- 8,698
Have you tried driving the "sports" tyres in the rain? They're atrocious! (That is: the sports hards are worse than the comfort softs.) I'm with SHIRAKAWA Akira, I feel their behaviour is more like a semi-slick, even if the grip level isn't quite up where we might "expect" them to be; remember GT5 doesn't seem to take contact patch size (properly?) into account, and it doesn't offer any real-world tyres at all.
So yeah, the tyre calculator works so long as you stick to dry tarmac, since the tyres have a nice linear progression in grip level, but the wet-weather performance clearly shows the intended differences in the three tiers.
- 36
- sparrow_ger
That's exactly where the problem of the tire system lies. On my (real life) VW Golf, I have the Potenza RE050A installed. It's a quite soft tire (Treadwear Index: 140) with decent grip, but it's still far from what a Sports Hard is in GT5. On the other hand the same (or very similar) kind of tire is used on Ferraris.
The important difference is the width: While I have installed 225/225 on my Golf, there are at least 245/285 (front/rear) installed at a Ferrari. So maybe the RE050A really IS a GT5 Sports Hard, if you look at the large versions of it.
So a certain type of tire in GT5 doesn't represent any specific type of tire in real life. Under dry conditions using a SH could give you the results that a real life large UHP tire (like a large RE050A) would. But by using a GT5 Sports tire to represent a real life "comfort" tire, you would get completely wrong results under wet conditions.
But I guess you are right: Generally spoken, it seems that under dry conditions you should use SH tires to represent the very large UHP tires of real life sports cars.
- 5,549
- Edison NJ
- jdmking13
- Lucid killer 58
This is what I'm feeling also. I don't even care about the skidpad G values. Did aot of research on tirerack.com combine that with logic and we are good.
- 10,456
- United States
- WrecklessAbandon
I've known the OP results for some time, though instead of using the g-meter, I went by cornering speeds.
I'm confused why a table disregarding this list
Why not a list using what is said to be found?
This explains (to me) why upgrading tire size is still not an option in GT after all these years.
I'm confused why a table disregarding this list
was made though.
Why not a list using what is said to be found?
Juz curious. The tire temperature should have big impact on the grip. So when testing on skidpad, what is the temperature(or color) is the lateral G measured? Also regarding downforce, most car has some level of aerodynamics to achieve downforce. Is the downforce on skidpad entirely negligible? In the GT5 implementation, is the downforce increased gradually with speed or a static value and is the orientation of the car a factor? For chaparral 2J and X1, the downforce is generated even at rest. What is increase in lateral G force on skidpad? The X1 hardly skid even with CS so the downforce shld be tremendous even when stationary.
Also is it a given that greater contact patch means better grip (thus higher lateral G) during cornering? I think there is some controversy on that especially if the camber and tire pressure also greatly affects the size of the contact patch. Larger diameter at same pressure usually only means different shape of contact patch instead of contact size difference. If that is the case, then GT5 model may not be entirely wrong.
Also is it a given that greater contact patch means better grip (thus higher lateral G) during cornering? I think there is some controversy on that especially if the camber and tire pressure also greatly affects the size of the contact patch. Larger diameter at same pressure usually only means different shape of contact patch instead of contact size difference. If that is the case, then GT5 model may not be entirely wrong.
- 220
- Buenos Aires, Argentina
- ASTRO_BS-AS
Hello to everyone !
Amazing thread. I´ll test some of this today at home
ASTRO_BS-AS (psn ID)
Amazing thread. I´ll test some of this today at home
ASTRO_BS-AS (psn ID)
- 1,233
- Patra
- Rotorist
I like you way of analyzing the factors that contribute to grip. You got some points. In general, I like the tire model of GT5. There is space for improvement of course, but it is way better than previous efforts. Don't forget that they got Enthusia's physics model employee. And Enthusia was the best console racing sim back then.
- 3,531
- London, Ontario
- Starky513
- 830
- JAKARTA
- GTIC_omDidit
bump this nice thread with question:
Has anyone tried /tested tire consumption on the 2.0 spec? i notice on pre 2.0 that Racing Hards vs Racing Softs only make 1-2 lap different (Rc hard lasts 1-2 laps longer than soft) thus its not useful for pit strategies.
The grip was surely different, but how about the consumption.
If they are much different now with 2.0 physics, then it will be very good for endurance strategies.
thx.
Has anyone tried /tested tire consumption on the 2.0 spec? i notice on pre 2.0 that Racing Hards vs Racing Softs only make 1-2 lap different (Rc hard lasts 1-2 laps longer than soft) thus its not useful for pit strategies.
The grip was surely different, but how about the consumption.
If they are much different now with 2.0 physics, then it will be very good for endurance strategies.
thx.
- 359
- Hong Kong
- PowderGuy
I have done 24h le mans with C60 Hybrid-Judd PlayStation Le Mans '05.
and Some X2010 and X2011 run in indy 500
In Le Mans Case, My car using Racing soft and AI C60 using Racing medium
We both getting in the pit and the Tire wear almost are same...
Also... X2010 and X2011 in indy 500, Fuel is Run out 99L, but Tire still 50% left with Racing Soft Tire....
Basically, Tire life time, all compound are same...
Racing Soft could replace Racing Hard any more...
- 830
- JAKARTA
- GTIC_omDidit
Dude, you saved my time.
I will try to confirm that tonight
I need this for upcoming championship season with my friends
- 359
- Hong Kong
- PowderGuy
My Friends said, due to 2.0 update... all tyre could allowed oversteer.
He also said, Sport and Comfont Tires have much more grip...
for my opinion... this change is apply for X2010 and X2011...
especially Racing tires.
But I would like Tire wear could reduce MORE
I would like Soft reduce to 100 km, medium 150km , Hard 200km (in 300Km race)
if possible, in shorter race (under 50 km), Tire wear reduction have 2X or more...
He also said, Sport and Comfont Tires have much more grip...
for my opinion... this change is apply for X2010 and X2011...
especially Racing tires.
But I would like Tire wear could reduce MORE
I would like Soft reduce to 100 km, medium 150km , Hard 200km (in 300Km race)
if possible, in shorter race (under 50 km), Tire wear reduction have 2X or more...
- 282
- RichiPuppy
Have you ever driven a real car with summer performance tires in the rain as opposed to seasonal tires, you get the same results.
- 2,254
- Burlington, NC, USA
- a_garris/Vol_Jbolaz
You have a column that lists your recommendation for tires that will mimic the car's real life stock tires. Could you add a column next to that that lists the stock tires for that car in the game?
For example, the Alfa 8C comes standard with SH in the game. You recommend SM to mimic real life.
For example, the Alfa 8C comes standard with SH in the game. You recommend SM to mimic real life.
- 5,549
- Edison NJ
- jdmking13
- Lucid killer 58
They should be CS.
- 830
- JAKARTA
- GTIC_omDidit
@TCSdisable
I've tried last night with a lot of 700pp LMPs at Spa.
With focus on 787B, racing hard could last up to 10 laps until tires remaining 30% with best lap 2:06.xxx
moved to racing soft, best lap 2:01.xxx and the tires last just about the same (10laps) when it remaining 30%. I push it more and it still driveable until 13 laps and the tires just 10-15%
Online lounge, 2.01 pysics, T500RS wheel
Conclusion:
Hard and soft compound's durability is just about the same.
PD please fix this.
I've tried last night with a lot of 700pp LMPs at Spa.
With focus on 787B, racing hard could last up to 10 laps until tires remaining 30% with best lap 2:06.xxx
moved to racing soft, best lap 2:01.xxx and the tires last just about the same (10laps) when it remaining 30%. I push it more and it still driveable until 13 laps and the tires just 10-15%
Online lounge, 2.01 pysics, T500RS wheel
Conclusion:
Hard and soft compound's durability is just about the same.
PD please fix this.
- 8,698
Not really. "Summer performance tyres" are a little slippery, but not like the Sports are in the rain in GT5. Have you tried them (with grip reduction set to "real")?
They are more like cut slicks / semi-slicks (look at them) than "summer tyres". Unless that's what you think "summer tyres" are.
- 28,471
- Windsor, Ontario, Canada
- Johnnypenso
Good job OP. I'm always interested to find out how the game really works behind the scenes. Intuitively, it always seemed to me to be a rather linear scale as far as tire grip goes, which makes sense as far as the game goes. Now if they'd only fix the tire wearing issue we'd be all set!!
- 2,254
- Burlington, NC, USA
- a_garris/Vol_Jbolaz
