GT500 dyno test on TG

[otispunkmeyer]

i see alot of people here, and on other sites, mostly american, gettin rather antsy about the Dyno test on TG

along the lines of "duh its not gonna have 500bhp at the wheels, wheel dynos only measure power at the wheels, engine is still 500bhp blah blah blah"

and to that i say this

its not beyond the engineers of this world to easily work out/back calc to get a good idea of power at the fly wheel. some use arbritary % to guesstimate and others can actually work out power at the flywheel by letting the car coast to a stop with the clutch pressed in.

you have losses from the gearbox, rolling resistance is alittle higher due to how the wheels sit on the machine, etc.... these can easily be accounted for.

granted its not as accurate as an engine dyno, but its not going to be too far off the mark.

so my question to you all : why do people think TG and the dyno guys would omit a very easy task like that?

out of spite?

[ruuman]

Oh jesus, like there wasn't enough talk about this crap in the episode thread already.

People seem to be missing the point that the lesser powered Rosch was the better car, so who cares about the GT500 having 450,500,600 bhp, it's the same arguement trying to explain to some why the Veyron is ground breaking not just because it has1001bhp.

[otispunkmeyer]

Originally Posted by ruuman

Oh jesus, like there wasn't enough talk about this crap in the episode thread already.

People seem to be missing the point that the lesser powered Rosch was the better car, so who cares about the GT500 having 450,500,600 bhp, it's the same arguement trying to explain to some why the Veyron is ground breaking not just because it has1001bhp.

the proud americans obviously care that a Uk motoring show got the BHP figure wrong for their beloved icon

roush btw

im just saying, people seem to get rather antsy about this supposed mistake and are being vocal about it, calling it a big mistake when i dont think it is. a good rolling road will probably produce fly wheel number autonomously.

[efoolution]

what i don´t get about all the Fuss aroudn this is why People actually think, that it´s acurate to say "this car has 500 hp", when it has substanially less. Why would anyone think that if a not small amount of Power is simply lost somewhere, it would still be right to say a car has 500hp. The Engine might have 500, the car not. And I (dont know about you *g*) dont drive a engine ... i drive a car. And if i look into my Cars Papers, it doesn´t say "Engine developes 50Hp" (good old Fiesta +g+), it says "Car has 50HP".

Disagree if you want, but I think Carmanufatures build Cars ... a finished Product. Not just Engines that they put in some Box and write Box 500 Hp on the Side. Because that Box is going nowhere with some 500hp Engine in it.

[Ventura6]

Originally Posted by otispunkmeyer

....granted its not as accurate as an engine dyno, but its not going to be too far off the mark.

so my question to you all : why do people think TG and the dyno guys would omit a very easy task like that?

out of spite?

Well, considering that the GT500 does have 500bhp at the flywheel, unless the SAE people are all lying to us, it's clear that they did omit something. Why that happened is anyone's guess. I think the problem people have is that in TGTBTU, there was such a stink made about the GT500 when Clarkson said it made 450bhp. So people, like me, were waiting for Top Gear to test it and get it right... but apparently they went out of their way to make it seem as though it has less than 500bhp. And I say "out of their way" because, how many cars have they dyno'd on Top Gear?

This is a conspiracy I tell you.

[Scott]

Automakers almost always quote crank horsepower (which is also bhp if you were not aware) and you have to subtract all of the loss. The generally accepted loss is between 8 and 20% depending on the tranny, drive type, blah blah. I would guess that the Mustang is in the midrange of that scale because it is RWD.... so let's just say for simplicity that it is 15%

If you take the 460 they got on the dyno and figure what number 460 is 85% of, you have your answer. In this case, it is 541 bhp. So based on that I would say the loss is LESS than 15%, probably more like 9 or 10 and at 9 you get 511 which is a bit more believable to me.

[efoolution]

Originally Posted by Ventura6

And I say "out of their way" because, how many cars have they dyno'd on Top Gear?

5 the two Mustangs, a Ferrari, a Maserati and a Lambo. At least, those I remember ...

[skilesca]

Well Top Gear does like to make a point about how shit American cars are. Quite frankly I agree. The problem is that Americans hate to be bad at anything so they look for any inconsistencies to point at and use as an argument. I quite feel for them as knowone likes to be told how shit something is when they are proud of it. Still they should get over it.

Anyways don´t take it the wrong way. Clarkson likes to bash even though he does infact like some American cars and so does Halmond but it wouldn´t fit with their controversial personalities.

It just wouldn´t be as fun if Clarkson didn´t talk about the war, Nazis or fat Americans.

[Masternate2071]

It's of no concern to me how much horsepower that thing has.

Its ugly.
It's too big.
The suspension is ancient.

I'd rather just have an Exige or something.

[otispunkmeyer]

Originally Posted by Ventura6

Well, considering that the GT500 does have 500bhp at the flywheel, unless the SAE people are all lying to us, it's clear that they did omit something. Why that happened is anyone's guess. I think the problem people have is that in TGTBTU, there was such a stink made about the GT500 when Clarkson said it made 450bhp. So people, like me, were waiting for Top Gear to test it and get it right... but apparently they went out of their way to make it seem as though it has less than 500bhp. And I say "out of their way" because, how many cars have they dyno'd on Top Gear?

This is a conspiracy I tell you.

i think i explained in the acutal ep thread about this.

i think, personally, that the dyno test was correct. it may not be to the SAE standards of course, but thats a US standard right?

anyway.

i explained that there is a multitude of other reasons why the car would be 50bhp down. fuel quality, air quality, engine up keep etc etc.

for all we know that GT500 could of needed a good oil change, been filled up with some cheap 95ron fuel from tesco with the added silicon in it and the engine might of been out of tune a little due to journos ragging its balls.

so i think the dyno test was correct for that car. im not sayin th GT500 doesnt have 500 bhp, im saying due to a set of undetermind circumstances, that particular car didnt have 500 like it should have.

[ascari_2]

I am not a fan of this car at all, but here's my beef. This is supposed to be a car show. I don't care whether it's a toilet with wheels, or a Bentley, represent it as what it really is.

The GT500 was thrown on a dyno to make 441rwhp. Figuring in the drive train loss it gives the engine right around 500hp. This IS what the company advertises. This IS what the car actually has. Yet TG goes out of their way to downgrade the car to say that it does not have as much power as it advertises.

Now maybe if every other manufacturer out there would advertise their number as whp rather then bhp, I would take that argument, or if TG themselves would stop quoting the bhp on every car they test. But why say that the M5 is a "500hp monster" when if we go by TG's logic it's "almost 500".

As for all of you who use the argument of "I don't drive an engine, I drive a car" well then guess what, you never drive the advertised hp. Go ahead and put your Focus, F355, Supra, Mondeo, or anything else on a dyno and see how close you come to the advertised hp.

The early episodes of TG were the most entertaining automotive show out there. Just the right amount of entertainment coupled with great reviews. Now this whole season seems to have gone way below their standard, and only to finish off with singling out a US car to point out it's non-existant power deficit.

Come on TG, point out the flaws that are actually there, don't make up stuff.

[SuperStalin]

ATTENTION!!!

The point of the dyno test was concluded with the Roush Mustang.
It's to show that a car with less BHP is actually much faster
thanks to an improved suspension.

[ascari_2]

Originally Posted by SuperStalin

ATTENTION!!!

The point of the dyno test was concluded with the Roush Mustang.
It's to show that a car with less BHP is actually much faster
thanks to an improved suspension.

How did you come to that conclusion.

[nist7]

Originally Posted by ascari_2

How did you come to that conclusion.

It's a basic, automotive fact. Well-setup independent rear suspension systems DO handle/corner better than live/solid axle suspensions. The GT500 was not made for road courses, it was made for the drag strip.

GT500, 447 rhwp (500 at the crank) laptime: 1:30

Roush, 3xx rwhp (415 at the crank) laptime: 1:28

[ascari_2]

Originally Posted by nist7

It's a basic, automotive fact. Well-setup independent rear suspension systems DO handle/corner better than live/solid axle suspensions. The GT500 was not made for road courses, it was made for the drag strip.

GT500, 447 rhwp (500 at the crank) laptime: 1:30

Roush, 3xx rwhp (415 at the crank) laptime: 1:28

I understand what you are saying and I'm not arguing about the numbers. But my question was how do you come to the conclusion that TG made the mistake of saying that the car was not a 500hp car to prove the fact that it's slower then the other mustang. There's no logic behind your statement at all.

[Roberto]

Come on TG, point out the flaws that are actually there, don't make up stuff.

What did they make up?

[dschiller]

Originally Posted by ascari_2

I am not a fan of this car at all, but here's my beef. This is supposed to be a car show. I don't care whether it's a toilet with wheels, or a Bentley, represent it as what it really is.

The GT500 was thrown on a dyno to make 441rwhp. Figuring in the drive train loss it gives the engine right around 500hp. This IS what the company advertises. This IS what the car actually has. Yet TG goes out of their way to downgrade the car to say that it does not have as much power as it advertises.

Now maybe if every other manufacturer out there would advertise their number as whp rather then bhp, I would take that argument, or if TG themselves would stop quoting the bhp on every car they test. But why say that the M5 is a "500hp monster" when if we go by TG's logic it's "almost 500".

As for all of you who use the argument of "I don't drive an engine, I drive a car" well then guess what, you never drive the advertised hp. Go ahead and put your Focus, F355, Supra, Mondeo, or anything else on a dyno and see how close you come to the advertised hp.

The early episodes of TG were the most entertaining automotive show out there. Just the right amount of entertainment coupled with great reviews. Now this whole season seems to have gone way below their standard, and only to finish off with singling out a US car to point out it's non-existant power deficit.

Come on TG, point out the flaws that are actually there, don't make up stuff.

x2

[Roberto]

Still confused...what did they make up?

[nist7]

Originally Posted by ascari_2

But my question was how do you come to the conclusion that TG made the mistake of saying that the car was not a 500hp car to prove the fact that it's slower then the other mustang. There's no logic behind your statement at all.

Ummm......huh?

Well I never said anything like that and I'm assuming you're talking to SuperStalin?

[nist7]

Originally Posted by Roberto

Still confused...what did they make up?

They did not make up anything.