Some Interesting Tests/Results

[Dom00000]

So I was curious as to how acurate pd made the cars in the game in relation to real life. Heres what I factored in: Horsepower,torque,weight, weight ballance, gear ratios, tires. My test car was the 2009 Chevrolet Corvette ZR1.

Stock specifications are as follows for the real life car.Horsepower:638Torque:604 Gear ratios (:1): First: 2.29 Second: 1.61 Third: 1.21 Fourth: 1.00 Fifth: 0.81 Sixth:0.67 Reverse:3.11 Final drive ratio:3.42 Curb weight 1519-kg/3348.82-lbs. The weight ballance is 51/49 or 51% in the front and 49% in the rear.

Now for the gt5 Zr1. When I bought it the power and weight was slightly off. The dealership shows the correct power numbers but the weight was less than the real life car about 11kg lighter. After I bought it, it didnt come with the power numbers shown in the dealer, it came with much less I think only 612hp even though it says 638. So to make up for this I decided to see if an oil change would make it go the correct power only to find out that it makes it too powerfull at 650hp. I did not do the oil change because I know that will raise the torque as well and you can bring torque lower by adjusting the engine power %. So by surprise i installed the sport intake manifold and racing air filter which brought the power of the car to 638hp and 604ft-lb. The rpms of the these number also stayed the same. Now lets move on to weight. Like stated earlier the gt5 car is 11 lighter than what it is in real life so I added 11kg to make up for it. Now the weight ballance was also not correct. In real life its 51/49 but in gt5 its the opposite 49/51 very strange huh. Also the transmission gear ratios in gt5 were all correct.

Now the real fun begins, testing the following numbers comparing real life vs gt5. I have tested 0-60mph, 0-100mph, and 1/4mile times. The real life times I found from various sources are as follows: 0-60mph 3.2-3.4s 0-100mph 7s 1/4 mile 11.2-11.3s Trap speed around 130mph. Using route X with an automatic transmission I got some interesting results. Soo as you all should know by know high end cars in gt5 come with sport hard tires. When I tested sport hard tires the times in gt5 were way slower than the real life times as an example I couldnt even get under 3.8s 0-60mph at 0.74gs using various launches. So I moved on the sport medium. These were also slower, I couldnt get under 3.5 0-60mph at 0.82 gs. Now for sport soft. using these tires I was able to match all times in real life. The sport soft tires numbers are as follows: at 0.89gs 0-60mph 3.2-3.4s 0-100mph 7s 1/4mile 11.3s. With a black screen launch only the 1/4mile was off at 11.403s but the 0-60/100mph stayed in the real life number window. Timed launches at different rpms produced much lower times compared to the black screen launch but all remained in the real life number window. The fastest 1/4mile time I got was 11.300.

Again I used an automatic transmission and no aids, completly stock except for those 2 upgrades to make the numbers correct and of course adding the sport soft tires. In conclusion I think that in order to get true to life physics (at least in a straight line) is to use sport soft tires on productions cars. Congratulations to Polyphony Digital for creating such a true to life experience in a video game! I think I am going to test other cars too including different drivetrains to truely see the accuracy of gt5, so far its looking pretty good. Also heres some pics.

 

[Samus]

Congratulations to Polyphony Digital for creating such a true to life experience in a video game!

Even though they didn't since you had to make many changes? Also the general rule of thumb is that the GT tyres are too grippy, not the other way around. So going up two grades to get correct results also seems off.

 

[Tornado]

No offense, but there have been many, many tests on this subject already; and the results of them generally contradict what you've presented (which actually shows that things are wrong anyway, since you had to jump through so many hoops to, let's be honest here, force the test results to line up how they should).

Sports tires on anything short of a Cup racer is generally well over the performance that these cars have in real life, and the overwhelming majority of the cars would come with, at most, Comfort Soft tires. And since the tire model in GT5 is so basic anyway (since tires function basically as a straight grip multiplier rather than working in tandem with the suspension), matching test numbers even with the proper tires wouldn't really mean much,

 

[Dom00000]

All that matter though is that you can create real life in the game no matter how many hoops are needed to jump through.

 

[gtnoobie]

Great read and tests. Interesting how difficult it is to get acceleration figures close to real life. I guess the lateral grip surpasses the real life counterpart resulting in unreal laptime.

 

[mistersafeway]

It is also possible that the tyres needed to be upgraded to make up for the automatic transmission, as the real car uses a manual and the acceleration results would have been reached after much testing with a professional driver. Still, a very interesting test and probably the first such test since 2.08.

 

[Dom00000]

It is also possible that the tyres needed to be upgraded to make up for the automatic transmission, as the real car uses a manual and the acceleration results would have been reached after much testing with a professional driver. Still, a very interesting test and probably the first such test since 2.08.

I would have used manual but I wanted to keep everything constant.

 

[Rotorist]

It is well known that lateral grip in GT5 is less than in real life's tires. But here, ZR1 has by default SH tires on which are very slippy for a 640HP car. So, IMHO SM are the best tires for supercars-hypercars.

 

[Exorcet]

I believe those real ZR1 numbers are from drag strips. Magazine tests get results more inline with sports hard and sports medium.

A better test would involve the averaging ZR1 mag test numbers and then comparing GT5 to the averaged data. Just because the virtual car was slower than the particular acceleration times you had does not mean that the car was modeled improperly.

On the tires, I'll agree with you. As has been said, GT5 tires are often considered too grippy, but this is for cornering. Off the line acceleration has them go the opposite direction to being not grippy enough. GT5's tire model is not perfect, and I find that reasonable acceleration times require tire upgrades because tire grip seems to hit an artificial wall at certain levels of acceleration (unless you're using GT5 magic AWD).

 

[mvpers]

just to throw another curve into the results, in the real world when cars are tested for magazines they adjust the numbers based on weather/etc,
often when i read performance data in car mags it willsay in small print that the data was weather corrected,etc.

there are a million variables in real life as well as in the game.

This is why magazine A get a 0-60 time for a car of 6.1 secs, and magazine B get 6.7 seconds

 

[MOTORTRENDmitch]

It is well known that lateral grip in GT5 is less than in real life's tires. But here, ZR1 has by default SH tires on which are very slippy for a 640HP car. So, IMHO SM are the best tires for supercars-hypercars.

Wrong... On SH cars like a ZR1 can surpass 1G

 

[JCH8r]

Well done. Thanks for going to all the trouble of working on this.

 

[phil_75]

But in real life tests are normally conducted with full tank and 2 occupants!

 

[SlipZtrEm]

All that matter though is that you can create real life in the game no matter how many hoops are needed to jump through.

Welp, by this logic, a lot of the other racing games out there are realistic too, as much as GT5.

💡

It's commendable you did all the testing (GT's been too slow (on average) compared to real life acceleration numbers for a while now, especially with FF vehicles), but if anything, it shows how unrealistic the game is, since lower-grade tires are needed in most cases to more accurately achieve the right handling stats, while stickier tires are needed for the straight line stuff.

 

[AERO_HDT]

... let's be honest here, force the test results to line up how they should).

I tend to agree with Toronado here. Any result is possible, given alterations and I think stating the obvious with a few minor tweaks is less interesting than perhaps running the car as close to stock in the game and then trying to explain anomalies/similarities etc etc.

What you're trying to do is almost impossible, (re: "million variables"). I don't think stickier tyres are really the problem for straight line acceleration tests, I think the problem is more track surfacing in-game versus a real life drag strip which has been rubbered in.

So the problem may not be with the car model itself, but rather the track and if that's the case, the tests are kinda... moot?

Still, keep it up, looking forward to your next run...

 

[GTP_CargoRatt]

No offense, but there have been many, many tests on this subject already; and the results of them generally contradict what you've presented (which actually shows that things are wrong anyway, since you had to jump through so many hoops to, let's be honest here, force the test results to line up how they should).

Sports tires on anything short of a Cup racer is generally well over the performance that these cars have in real life, and the overwhelming majority of the cars would come with, at most, Comfort Soft tires. And since the tire model in GT5 is so basic anyway (since tires function basically as a straight grip multiplier rather than working in tandem with the suspension), matching test numbers even with the proper tires wouldn't really mean much,

Agree.

 

[diegorborges]

You could redo these tests after 2.09... I'm feeling some tires a bit more grippy on accelerations but a bit (I said A BIT) more complex and less grippy when cornering...