Why are the horsepower readings different then real life?

C

ControlledAnger

101
ControlledAnger
For my specific case i only want to discuss the supra, because this is the car im trying to get a replicated one of to as close to real as possible.

So a 1997 Toyota Supra RZ has these stats below;

In game (with oil/engine rebuild)= 342hp/412 ft-lb
In game (with oil)= 324 hp/390 ft-lb
In real life= 320 hp/ 315 lb-ft

is lb-ft different then ft-lb
also is the readings on gt5 hp and in real life bhp?
 
freight48
I think a 4 HP difference is not very noticeable.
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Not just that, even 2 brand new engines of the exact same type are different. Maybe minimal, but still different. Let alone after some ware and tare from 2 different people with different driving styles.
 
Ever car is different. if you went out and bought 2 brand new cars and dyno them they both would have different numbers (small difference, it could be 1-10 HP and it could be even more)
 
ControlledAnger
also is the readings on gt5 hp and in real life bhp?
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In my version I don't even have HP its in kW, which is stupid! They could have just stick to one definition! I have to convert everytime I want to compare tunes etc.

Same for mph and km/h but in this case its not that annoying...
 
Basilea
In my version I don't even have HP its in kW, which is stupid! They could have just stick to one definition! I have to convert everytime I want to compare tunes etc.

Same for mph and km/h but in this case its not that annoying...
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What youre saying your veyron is in kW but everthing else is in hp? :S

I think people in countries that use kW have kW in their game only.

I dont know whats goin on with you.


But I am in Asutalia, we use kW and all my gt5 is in HP, which I much preffer.
 
No all cars in my GT5 version are in kW... The Swiss version of the game is all in kW, I don't know about the rest of Europe, though.

I'm more used to PS which is the german abbreviation for HP...

@xSNAKEx by the way where is Asutalia? ;)
 
I know, right? PD should include a disclaimer at the start of the game that tells you that despite the cars being modeled as closely as possible to real life, they're not always entirely 100% accurate.
 
Basilea
No all cars in my GT5 version are in kW... The Swiss version of the game is all in kW, I don't know about the rest of Europe, though.

I'm more used to PS which is the german abbreviation for HP...

@xSNAKEx by the way where is Asutalia? ;)
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lol its my own island.

haha its actually a pretty mad name!
 
xSNAKEx
What youre saying your veyron is in kW but everthing else is in hp? :S

I think people in countries that use kW have kW in their game only.

I dont know whats goin on with you.


But I am in Asutalia, we use kW and all my gt5 is in HP, which I much preffer.
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I'd prefer kW/Nm. It's makes comparing figures to real life cars in Aus in my head so much easier. I have my cars list spreadsheet make the conversion automatically for me.

Better yet, why can't you choose what you like, the way GT4 had it?
 
Don't a lot of car makers actually under quote the horsepower numbers? Maybe these horsepower figures are the true ones.
 
sumbrownkid
Don't a lot of car makers actually under quote the horsepower numbers? Maybe these horsepower figures are the true ones.
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Especially Japanese automakers. HP numbers always vary from car to car. There is noway cars come from the factory with the same exact specs.
 
ControlledAnger
For my specific case i only want to discuss the supra, because this is the car im trying to get a replicated one of to as close to real as possible.

So a 1997 Toyota Supra RZ has these stats below;

In game (with oil/engine rebuild)= 342hp/412 ft-lb
In game (with oil)= 324 hp/390 ft-lb
In real life= 320 hp/ 315 lb-ft

is lb-ft different then ft-lb
also is the readings on gt5 hp and in real life bhp?
Click to expand...

Jacob6875
My completely stock RX8 with oil change is at 254 HP

In real life they produce 232hp. Pretty big discrepancy if you ask me.

proof if anyones interested
http://www.mazdausa.com/MusaWeb/displayPage.action?pageParameter=modelsSpecs&vehicleCode=RX8
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LTRules21
same with a 3000gt vr4, used it has 276hp in game, and in real life it has 320
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My guess would be that PD was very sloppy in translating real-world hp/kW into game terms. and I would furhter venture that this slopiness came about from the PD team using different sources of hp/kw info! It would be nice if PD would release where they obtained the car hp/kw values (3rd party, manufacturer, out of thin air, guessitimates, etc).
 
Ford Australia and their performance arm FPV (Ford Performance Vehicles) are guilty of heavily understating their forced induction engines.

The turbo inline 6 in my Falcon is supposed to be 270kW (362hp) but the dyno says 247kW (331hp) at the wheels. So it's more like 300-310kW (402-415hp) at the flywheel. And I know of several others.

FPV have just finished building a new V8 for the Falcon which is a low-boost supercharged version of the Mustang's new 5.0L Coyote V8. It's supposed to be 335kW (449hp). A magazine reviewing this new car/engine put it on two different dynos and it's making nearly that at the rear wheels.
 
You also have to remember that some cars were 'rated' pre-new SAE ratings. HP ratings are lower now on a car that hasn't changed at all.
 
ControlledAnger
is lb-ft different then ft-lb
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I was going to say that they're the same, but Wikipedia seems to disagree with me.

It lists pound-feet as torque and foot-pounds as energy. However, when reading the pound-foot article, it also says that foot-pounds are also a measure of the same thing, which agrees with my original stance. It says that it was intended for "foot-pounds" to be reserved for energy to alleviate confusion.
 
sumbrownkid
Don't a lot of car makers actually under quote the horsepower numbers? Maybe these horsepower figures are the true ones.
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this right here

a late nineties supra turbo is rated at 320 in export markets...
manufacturer are supposed to measure it straight on the flywheel, but when you put those on a dyno, a new 2JZ-GTE will put out about 320... to the wheels.

I'm thinking PD uses dyno chart (which gives varying results by brand) and then "reconvert" to "brake horse power" (brake dyno, taken straight from the flywheel), probably using some convertion standard

I got many exemple of this (from supraforums, supramania, supraquebec and torontosupraclub, all supra owners group)

a jdm supra (RZ) with some 10 years of use, rated at 280hp put out 326 with only what GT woud call a "sport exhaust". That's quite close
 
Yeah, strange. When something is XX.XX (dot in the middle) it's usually something multiplied by something, so the order shouldn't matter.

However, if it's XX/XX, it's something divided or "per" something so the order is important. eg. metres per second (velocity) is m/s. Seconds per metre is wrong.

EDIT: BTW I've been comparing this: 0km cars vs. 0km with oil change vs. 2nd hand vs. 2nd hand with oil change vs. 2nd hand with oil change/engine overhaul.

Doing 8 different cars Mercury XR-7, FocusST, Veyron, Amuse CarbonR, Acura CL3.2, Cadillac Cien, Autobacs Garaiya to X2010 I get:

These percentages are all compared to the baseline brand new 0km car with no oil change.

0km baseline figure

0km with oilchange +5%

2nd hand +3% to -1% (it depends on how many kms ranging from run in to worn out)

2nd hand with oil change +8% (run in) to 0% (120,000kms)

2nd hand with oil change and engine overhaul +8% (run in) to 0% (120,000kms)

With hardly less than 1,000kms the engine overhaul make no difference, but get over 10,000 and it does, and over 120,000kms on my X2010 brought it backup to equal with a 0km oil-changed X2010.
 
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Also I dont know about other country car, but japanese 90's car were famous to have more HP than the stat were saying. For example GTR were suppose to have 280 HP but always end up around 300-350 HP if you test them after break in, same for supra's I think. This as to do with japanese regulation I think too. So maybe that's what PD was trying to do.
 
276 gentleman's agreement in Japan.

Old Japanese agreement pre-2005 has all cars electronically limited to 155mph and 276HP I believe.

I know for a fact that the R34s and R33s at least pumped out 300HP.
 
You gotta make sure you're comparing the exact same Spec of the real life car, there are many different versions of the same car. Even still it's expected that there be a 1-10 hp difference.
 
Watto
EDIT: BTW I've been comparing this: 0km cars vs. 0km with oil change vs. 2nd hand vs. 2nd hand with oil change vs. 2nd hand with oil change/engine overhaul.

Doing 8 different cars Mercury XR-7, FocusST, Veyron, Amuse CarbonR, Acura CL3.2, Cadillac Cien, Autobacs Garaiya to X2010 I get:

These percentages are all compared to the baseline brand new 0km car with no oil change.


2nd hand with oil change +8% (run in) to 0% (120,000kms)

2nd hand with oil change and engine overhaul +8% (run in) to 0% (120,000kms)
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When you are doing an overhaul you are also doing an engine oil change.

Try this the opposite way (first overhaul, then oil change) and the game tells you the oil is in good condition (because it has been obviously changed during overhaul).
 

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