Wondering what car to buy? Try the GT4 Car Database

[RallyRacingFan]

To Famine: I think the used cars have varying amounts of power depending on their mileage. In your Excel spreadsheet you have:

Mitsubishi Lancer EvoV GSR '98     U	4W	292	1360	214.7

I happened across this car today (testing it for the effect of oil changes on used cars) and noted different figures:

                      List    Specs   Oil    rpm
Lancer EvoV GSR '98    280     296    311    6500
                       38      40.17  42.18  3000

(List) is the power/torque shown in the price list, (Specs) is the values shown on the spec sheet when you attempt to buy the car and these are also the values which show up in your garage, (Oil) is after an oil change.

Two things to note:
1) My power is different to yours so either one of us made a mistake or the power for used cars varies with mileage.
2) Changing the oil in a used car also gives a 5% power and torque boost.

Don't know what the policy for double posting on these boards is. Is it OK to split different things in multiple posts? I thought it would be less confusing this way. Please advise if it is not acceptable.

 

[RallyRacingFan]

If you turn the AutoSave feature off, you'll be okay - go to Options, the "Other Options" at the bottom then set the last thing to "Off" instead of "On", and it'll stop Autosaving.

Aha! Thanks. I wish I had known that before I blew nearly 300,000 credits buying the entire Subaru line up! Oh well, I can always get more and I had a lot of fun doing the Subaru 360 race.

Thanks for the effort though.

Well that effort may have been in vain but I do have a couple of prize cars which are on your list but don't yet have power ratings. When I get to play again I will post the power and weight for the prize cars I have. I do know that the Cadillac CIEN has a 7500cc engine and makes 760PS (798PS after oil change). Didn't write any of the others down though I'm afraid.

One last thing. It isn't only the 280PS cars which have different specs in the showroom and in the garage. I bought the ASL Garaiya '02 (because it looked cool and I needed somethng less than 4000mm long for a race) and I discovered the following:

                  Shop  Garage  Oil     rpm
                  -------------------------- 
ASL Garaiya '02   204    201    211     7200
    800kg         21     20.99  22.04   5200

Also the Garaiya is too powerful for the Japanese Small car cup (4000mm or less) which is what I bought it for.

 

[Famine]

I'm picking through the Used Cars as we speak. I suspect the majority of the remaining cars I've not yet accounted for will be Used, rather than special prize cars. That said, if the "rumour" of every car from previous GT games is to be believed, I'm still several F1s, a GTO LM, an FTO LM, a Cerbera LM, an Elise GT1.... *waffles on* ... and a Dodge Phaeton short...

The Used car stats make me furrow my brow in a confused manner. No doubt I'll work it out... I've still only done 8 licence tests in the game so far...!

 

[vipersan]

vipersan - Used cars are marked. "Legend" cars are also marked (those available in dealerships from the second option - its caption reads "Legend Cars"). The list of used cars changes every 10th day (note not every 10th game day - it changes on 10th April, then 20th April, then 30th April and so on, but the game starts on the 2nd April). However, I'm merely marking out ALL of the available used cars for each manufacturer. I am putting together an HTML file for what cars are available when, and will pick out rare cars/colours within that. An Excel file with all that in would contain about 70 sheets...

Well, you did explain most of that before . I know that cars are properly marked. I was just wondering about those rare cars, that cannot be bought from a dealer.
For example: (I am not sure, but as I've seen from pics and data so far) the Audi S4 (new model) is available in car dealer for 5.543.000Cr (maskrider's pics) but there is no older model (the one featured in GT3), which is available under used cars section for 4.629.200 (again maskrider's pics). So that could be one of them. But as you pointed out, it's all in your work plan, so I'm happy and can't wait to check it out. Thank you.

 

[jctg]

While you're at it, quit the false-reporting of power too. WE get it that there was a "Gentleman's Agreement" limiting cars to 280PS. We also know that it was complete codswallop and the cars have been running in excess of this for years. Most importantly, we don't care. We just want to know what the power of our cars in the game are. On the face of it, the 280PS RX-7 seems a better choice than the 280PS Evolution VIII, because it's lighter. But the 280PS EvoVIII really has more than 300PS and actually has a better PWR than the RX-7.

Wouldn't surprise me in the least that KY was specifically asked by car manufacturers not to do that. Just think about it, if they made the effort to stay below 280PS when they quote numbers, why would they let KY show the real figures? And I bet none of the buyers of those real cars give a **** if their cars are over 280 either.

Excellent work with the excel sheet. 👍

 

[Famine]

1) My power is different to yours so either one of us made a mistake or the power for used cars varies with mileage.

Given that the cars on sale have a minimum (thus far) of 29,000km on the clock (about 18,000 miles) and cars in GT3 ran in and out again in under 500 miles, I doubt it. But you never know...

I've gone through the first 3 Used Car lists (Days 1-7, 8-14, 15-21) with a fine toothcomb, and have some new numbers, but it's far too late at night to upload them...

An update tomorrow, methinks...!

I might create a separate thread for the Used Car list database. It's going to be a 99-sheet Excel file when it's finished...

 

[donbenni]

Nice one 👍 Good to see it made by a Brit so therefore use of BHP and BHP/tonne. Cool stuff

 

[flamingwonky]

Very nice work, Famine. Now if only anyone can start with the tuned autos stats, as I imagine you're too poor in-game. Gameshark anyone? Disclaimer: I do not approve of using the GameShark for Gran Turismo or other titles. However, it's nice for getter enough $$$ to work on the car tuning .

 

[S13DRIFTSPEC]

Good job famine but it looks like you did the power to weight ratio the hard way. It could have saved a couple hours by inputing formulas for it instead of the actual numbers. For example. For block F7 "=D7/E7*1000" (with out the quotations) from then on its a simple click and drag on the corner of the block then copy and paste everytime you go to a new country. You should use it when you have the hp and weight of the tuned cars it'll save you couple hours.

 

[Famine]

The problem with dragging and dropping formulae is that they screw up your formatting.

I've started to do it for more recent cars (I use "=D#/(E#/1000)" - or actually I don't, since I've now added a torque column too - in lbft ). But it's really not THAT time efficient, once the database is in place.

 

[Mukai]

Awww, seeing you guys calculate a power:weight-ratio is causing real headache to me.


e.g. a car's weight is 1500kg and has 500PS, so the PWR ist simple 3.0!
and if you lightweighten that car to 1250kg it has a new PWR of 2.5
if you then raise the power to 1000PS it has a phenomenal PWR of 1.250!

What's so hard to calculate this way?
Its normal to call a car a supercar, if its PWR is below 3.5!

greets
Mukai

 

[Famine]

Except it isn't. The clue is in the phrase "Power-to-weight ratio". Power to weight. Measured in horsepower (power) per tonne (weight).

You are calculating the weight to power ratio. Measured in kg (weight) per PS (power).


Anyway, condescending, yet wrong, fools aside, I've updated the file again. This time it takes account of the correct power of every single purchaseable car under 11,000,000 credits - including all used cars on the first and second lists (up to day 14). I'll be a-thievin' maskrider's save to complete the rest of the purchaseable dealer cars ASAP.

The Used Car database is coming along stormingly. And you'll be pleased to hear that in the meantime I've been able to gold my B-licence (so the three prize cars are also included) and the first four A-licence tests too. And apparently that accounts for precisely 0.0% of the game...

 

[poppadom]

good job, how do you know this? I am from london (well i live in brisbane) and tried to do a database using the game, but it don't come out 'til FEB 25 on amazon whilst in aus MAR 29 you must know alot of ppl if u own gt4. anyways you saved me **** loads of time, cheers

 

[RallyRacingFan]

To Famine:

Is power to weight really a good measure of the performance potential of two cars? It seems to be only useful if the weights are roughly the same. If one car is a lot lighter than the other comparing PWR doesn't tell you a lot.

Car A: 400HP, 1000kgs, PWR = 400
Car B: 800HP, 2000kgs, PWR = 400

Assuming they both have the same CdA then Car B is going to have:

Better 0-60 time
Better quarter mile
Higher top speed

This (as you know) happens because the higher HP car has more HP to overcome aerodynamic drag (which I defined as being equivalent for the two cars). At average race speed drag might be draining around say 50HP from both cars.

At average race speed:
Car A: 350HP, 1000kgs, PWR = 350
Car B: 750HP, 2000kgs, PWR = 375

Car B's superiority becomes apparent. At faster tracks drag would be draining even more HP and the Car B superiority would be even more pronounced.

Of course to compute this for your car database we would need width and height information for every car along with Cd. Getting Cd could be difficult.

 

[Scaff]

To Famine:

Is power to weight really a good measure of the performance potential of two cars? It seems to be only useful if the weights are roughly the same. If one car is a lot lighter than the other comparing PWR doesn't tell you a lot.

Car A: 400HP, 1000kgs, PWR = 400
Car B: 800HP, 2000kgs, PWR = 400

Assuming they both have the same CdA then Car B is going to have:

Better 0-60 time
Better quarter mile
Higher top speed

This (as you know) happens because the higher HP car has more HP to overcome aerodynamic drag (which I defined as being equivalent for the two cars). At average race speed drag might be draining around say 50HP from both cars.

At average race speed:
Car A: 350HP, 1000kgs, PWR = 350
Car B: 750HP, 2000kgs, PWR = 375

Car B's superiority becomes apparent. At faster tracks drag would be draining even more HP and the Car B superiority would be even more pronounced.

Of course to compute this for your car database we would need width and height information for every car along with Cd. Getting Cd could be difficult.

Not always true as a lighter car would on balance have greater cornering and braking ability, due to a much lower workload on the tyres. This would be very evident in cars weighing 1000 and 2000 kilos repectively.

Also while your point on top speed and 1/4mile times are valid, in a 0-60 shoot out with two cars of an equal PTW ratio, the ligher car will normally perform as well if not better than the heavier car. At speeds upto 60mph drag would be a negligable factor.

Power to weight (and Famine is quite correct in how these are calculated) is not an indication of a cars overall ability, as no single factor can be.

In your example the lighter car would almost always have the advantage on a tight track with a lot of corners strung together; such as the 'ring. However the heavier car may have an advantage on a high speed, less technical track; such as Fuji.

At the end of the day it is a means of comparison; but it is not definitive. Because no single data figure for a car can be.

Used in conjunstion with other informatio and its a valuable tool, on its own its just another number.

 

[RallyRacingFan]

Not always true as a lighter car would on balance have greater cornering and braking ability, due to a much lower workload on the tyres.

Ahh you mean the brakes would cook and the tires would get shot on a heavier car? Both excellent points, a heavier car will likely need to pit more often. However braking rate is normally a function of max tire grip rather than brake power. Most brakes have the ability to lock the wheels. Since the number of g's the tire can pull under braking is independent of the car's weight then I don't see that a lighter car is going to have a significantly shorter braking distance or higher cornering speed. The only thing that can help you is aerodynamics. Counter-inituitive I know ... I'll find some supporting references for this claim and get back to you.

Also I'll build two identical PWR cars (weight reduction kit on one, hp enhancements and extra weight on other) and test the 0-60 theory tonight. Hopefully I have enough cash left to buy two heavy cars, went on a bit of a buying spree last night.

 

[Mukai]

In german we call it "Leistungsgewicht"
Thats the same es Power-weight-ratio.
Cause the PWR does only say how much weight 1 PS has to move.
So if the PWR is 3.0, that means that 1 PS has to push 3 kg
So a standard car with 1500kg and 150PS , here a PS has to move 10kg.

You yee your Calculation is totally wrong. as you can see on the Daimler Benz 1886. It must have a PWR way more than 100, while the Le Mans Racer tend to have a PWR under 1.5

 

[Scaff]

Ahh you mean the brakes would cook and the tires would get shot on a heavier car? Both excellent points, a heavier car will likely need to pit more often. However braking rate is normally a function of max tire grip rather than brake power. Most brakes have the ability to lock the wheels. Since the number of g's the tire can pull under braking is independent of the car's weight then I don't see that a lighter car is going to have a significantly shorter braking distance or higher cornering speed. The only thing that can help you is aerodynamics. Counter-inituitive I know ... I'll find some supporting references for this claim and get back to you.

Also I'll build two identical PWR cars (weight reduction kit on one, hp enhancements and extra weight on other) and test the 0-60 theory tonight. Hopefully I have enough cash left to buy two heavy cars, went on a bit of a buying spree last night.

Weight is an integeral factor when calulating grip for a tyre, as is explained in the following except from 'The Physics of racing"

"You will also recall that a tire has a limited ability to stick to the ground. Apply a force that is too large, and the tire slides. The maximum force that a tire can take depends on the weight applied to the tire: where is the force on the tire, is the coefficient of adhesion (and depends on tire compound, ground characteristics, temperature, humidity, phase of the moon, etc.), and is the weight or load on the tire. "

Read the whole thing here

http://www.miata.net/sport/Physics/07-Circle.html

The entire series is an excellent (if a bit heavy going) work on how the physics of racing works, it is very, very helpful.

Weight (sprung and unsprung) is a factor that must be applied when looking a grip levels for a car, and in general a lighter car will be able to travel faster than a heavier car before the grip level is exceeded.

 

[RallyRacingFan]

Weight is an integeral factor when calulating grip for a tyre.

That's the counter-intitive part I mentioned, weight is critical but then when you do the math it goes and gets cancelled out.

Stopping Distance for Auto

"Note that this implies a stopping distance independent of vehicle mass."

 

[RallyRacingFan]

You yee your Calculation is totally wrong. as you can see on the Daimler Benz 1886. It must have a PWR way more than 100, while the Le Mans Racer tend to have a PWR under 1.5

Since Famine generously provided an Excel spreadsheet you have the option of converting his PWR formula into any alternate system you desire.

 

[Scaff]

That's the counter-intitive part I mentioned, weight is critical but then when you do the math it goes and gets cancelled out.

Stopping Distance for Auto

"Note that this implies a stopping distance independent of vehicle mass."

Damn, being at work is a pain, no reference books to hand and also running a training course.

Will have to get back to this from home tonight.

 

[DQuaN]

WOW the Toyota in the carlist is unbeliveable!!!:

L Toyota 7 '70.....MR.....789.....620.....1272.6

What is this car? An F1 car? Any pics?

 

[Scaff]

That's the counter-intitive part I mentioned, weight is critical but then when you do the math it goes and gets cancelled out.

Stopping Distance for Auto

"Note that this implies a stopping distance independent of vehicle mass."

Right found it; you are quite right with regard to weight and grip levels; I totaly forgot the cancelling effect of the full calculation (my big bad).

But, weight does play a role in cornering.

As I am at work at present, I don't have the time to write it all out here. However take a look at the following:
http://www.miata.net/sport/Physics/13-Transients.html

With regard to braking, you are right that Mass does not affect braking distances; but ligher cars generaly have a lower centre of gravity than heavier cars (this is a very general point and mainly applies to lighter sports cars). While the lower COG does not greatly affect the cars braking ability, it does effect the cars braking stability during the weight transfer.

The main effect of this is on driver confidence, the best example I can give of this is the very exagerated effect you get when braking hard on a motorbike. Due to the far higher COG (when compaired to a car) a bike is always more unstable during braking than a car (the loss of two wheels does not help). When you compare braking times and distances between bikes and cars the difference is quite visable.

BTW - interesting subject this

 

[RallyRacingFan]

BTW - interesting subject this

I now know why it is that the petrolheads I knew when I was younger didn't really seem to know all that much about the cars they were obsessed with. As soon as you try to get beyond the surface it all becomes horribly complicated.

For me it all started with GT3. I read someone's car list and concluded, since it was used that way in magazines and every car list, that PWR was the single data figure which could be used as a definitive means of comparison. On the strength of PWR alone I bought a Lotus Elise thinking it was going to dominate. Much to my surprise it was not competitive in the races I entered it in despite the PWR indicating (to me) that it should have been.

Experimental evidence had shown that my theory on PWR was junk so I started trying to come up with a better way to measure performance. I settled on 0-400m times as a decent yardstick ... and set about calculating the 0-400m times based on specs. I started researching and spent many days refining my model. Some way in I realised I needed to determine grip limits for takeoffs and learned about the WEIRD properties of tires. I had to read the same infomation (acceleration/deceleration limits independent of weight) on several websites before I believed it. Still seems a little fishy.

Since I was only interested in straight line 0-400m testing I neglected to investigate grip in cornering much. I had believed the same weight cancels out effect would apply.

So here is the basic challenge: Given that Car A has 400HP and weighs 1000kgs, how much HP would CarB need (weighing 2000kgs) to achieve the same lap times in GT4 B-Spec mode around trial mountain (assuming equivalent CdA). It is possible to come up with a single number, while not definitive, that can be used as a more accurate means of comparison between two cars than PWR?


I plan to do the 0-60 shootout but I haven't been able to track down where the DataLogger in GT4 is hiding.

 

[TheCracker]

PWR is probably your best bet - but like Scaff mentioned, there are no mathmatical equations that could realistically give you a better idea due to the fact that there are so many variables that can effect lap times. Tyre contact patches will differ on a 1000kg car to those on a 2000kg car - the 2000kg will undoubtibly have wider tyres. The weight distribution again will differ, leading to different loads on different tyres under braking, cornering and acceleration. Even if you managed to find these two hypothetical cars in GT4 the gearing in both cars would probably differ - and i very much doubt that even GT4's physics engine takes weight distribution or many other factors into consideration.

If it was possible to produce a grip-to-weight ratio you could potentially combine the PWR and GWR to get a better idea of possible lap time comparisons

 

[El_Torero]

ok, i've already posted something in the other thread (jkrobby's) but i've liked the idea going on around here about the econometric formula...

The only thing we need is a common unit of performance. Wich could be "seconds it takes to go around Tsukuba for 1 lap." (lets call this "T") for example . To make it as linear as possible it should be done in b-spec mode with a constant b-spec driver points. This is a way of including "handling" into the formula, something non-measurable.

the formula then would be:

T= b1 + (torque)b2 + (HP)b3 + (weight)b4 + (drive train)b5 + ...any other... + e

We should only need to this with about 50 - 100 cars, and then extrapolate it to the rest. This should give as a certain degree of confidence,of around 95%, if the cars are well chosen. Also, the more the better.

After that it is only a matter of dividing how much it costs by "T" (price/T) and there you would have a quite interesting ratio of QUALITY-PRICE. This is, the best your money can buy.


..... Ok..... ummmm.... it has all come from the top of my head right now so i would guess it doesn´t make any sense at all. But anyway, I leave it there as a source of inspiration... maybe someone is able to understand what i mean and can explain it better.

P.S. If i've got time later i'll look over it to make it clearer.

CHEERS

 

[Scaff]

IRL I have always found the 0-100mph-0 test a very good measure of a cars outright performance (not handling); as it covers acceleration from rest, acceleration through the gear, gearing, aerodynamics, braking performance and stability.

The Autocar annual 0-100mph-0 challenge is always worth a look, you may even still find some of my posts in the Automotive threads.

The current world record holder is the Ultima GTR, info can be found here (along with some vids)

http://www.ultimasports.co.uk/record.html

Its time, 10.3 seconds.

As far as handling goes, I have always found this to be a much more subjective matter and not one I have every been happy to put a figure on. The closest to a figure I would trust would be a slalom time and average speed; for me skidpan tests in lateral g's are of no benefit other than a rating of the tyres grip levels.

 

[Famine]

In german we call it "Leistungsgewicht"
Thats the same es Power-weight-ratio.
Cause the PWR does only say how much weight 1 PS has to move.
So if the PWR is 3.0, that means that 1 PS has to push 3 kg
So a standard car with 1500kg and 150PS , here a PS has to move 10kg.

You yee your Calculation is totally wrong. as you can see on the Daimler Benz 1886. It must have a PWR way more than 100, while the Le Mans Racer tend to have a PWR under 1.5

No, my calculation is totally correct.

YOU are talking about "Weight-to-power ratio". This involves reducing the power to 1 and reducing the weight proportional to that. 1000kg and 50hp = 20:1 = 20 kg/PS. Weight-to-power.

I am using "Power-to-weight ratio", where one reduces the weight to 1 and reduces the power proportionally. 50hp and 1000kg (1 tonne) = 50:1 = 50hp/tonne.

PWR (Power-to-Weight ratio) is measured in power-units PER weight-unit - hp/tonne. WPR (Weight-to-Power ratio) is measured in weight-units PER power-unit - kg/PS


RallyRacingFan - I agree. It's merely included as a reference figure, so you don't have to calculate it yourself. That's why I've started including torque figures too. "Torque" is a very much mythical beast (although in reality it's actually "Power" that's the myth) and there's often confusion as to what it does, but if there's two cars with 200hp and 1200kg, people might like to know that one has 220 "torque" compared to the other's 190 "Torque"*


poppadom - I imported GT4 and an NTSC/J PSTwo. My Japanese is okay, which helps, although it's improving now I'm totally immersed in reading it. All the time...


*Figures quoted may or may not be relevant to any given car in GT4. And yes, I am perfectly aware of the units of torque, thank you.

 

[bramvanuytven]

is there a ferrari in GT4???
Can You drive endurance races in the b-spec mode?

 

[El_Torero]

you are mocking me... aren't you?