CHUCK your ok in my book..
Can anyone tell me why the 2011 has 20s out back and 19s up front?
- Thread starter James Rodriguez
- Start date
I like Chuck also............:thumbsup:
Maybe a poll?? :shrug:
This thread should have been titled "A discussion about the 2011 GT500 and 20's in the rear, 19's up front, and Chuck!"
R
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I like Chuck too but after awhile.........Lord help me........geez.......but it's all good
he brings it on him self. if he would learn when to shut his mouth(err, fingers?), then he would never end up in these situations, thread after thread.
I'm keeping the "unofficial Chuck poll".........
Currently Chuck is on the "like" side........I think? :shrug:
Chuck- Where are You, when we are discussing You?
R
Currently Chuck is on the "like" side........I think? :shrug:
Chuck- Where are You, when we are discussing You?
R
quick aside, i certainly don't dislike chuck, this place wouldn't be the same without him
The bigger the wheel the worse the traction.
Chuck - One thing to add to all of the uninformed "Poser", "DUB" and "Gayish" comments in this thread..........
Yes, a larger wheel does look better than a black rubber tire, so if that means it is a poser, then that discription is legit, BUT the sport and specialty car manufacturers (all of them) are in business to sell their performance cars, yes posing is nice, but $$$ are the bottom line. If all of these factory built performance cars are for some strange reason being built with larger wheel combo's there may be a reason, because they are faster than the competition and last years model, maybe? In addition to looking good, the number 1 goal is to be faster than the competition when the magazine hits the news stand, if they are slower, the press (and buyers take notice). <<<When I say faster, that means faster in all ways including rights and lefts. As all of the current performance car offerings are getting stronger, they are also going faster and handling better............but that goes against "the larger wheel is not as good theory", how can this be??? since it is the tire that makes this all happen (or not). Where the rubber meets the road..........literally. :thumbsup:
As a note to this^^^^^^. If straight line performance was the only goal, the car sales of that specific car would suffer. I believe through extensive testing, far beyond MM&FF or any other isolated magazine tests, the auto manufacturers have found that an all around better performance tire wheel combo is with a larger wheel, and since it has now been established (even by one poster in this thread) that his 20" (with tire) is the same as, or lighter than his 18" (with tire), the whole "heavier on each corner thing" (spinning mass) is quickly debunked when comparing same width and diameter 18" vs. 20".
I agree that some cars don't look right with larger wheels. I have seen larger wheels 21's, 22's on Mustangs, they look out of proportion to the car and the wheel well. Larger, even for posing purposes is not always better. If you have to jack the car up to get "larger" underneath, it definitley is not better. On this note, if Ford were to open up the wheel wells even futher in future Mustang models then 20's "could" look small if we are comparing "poses". <<<At that point we will be discussing how good the "old school" 20's looked and performed.
R
Rotational inertia of a 20" wheel and an 18" wheel that both weigh the same is not equal. The inertia is a combination of weight and distance from the center axis. So the bigger wheel moves the important weight further and further out.
Also, smaller wheel with more tire is always going outperform. That is why racecars have tiny wheels and giant tires.
http://co2calculator.files.wordpress.com/2008/11/2008_mclaren_f1_car.jpg
20s look nice but they definitely are not better for performance.
subscribing...
You sold me on that evaluation, and that F1 car certainly has a tall sidewall. I guess that for a production performance car, the manufacturers see things differently and offer accordingly, to make their packages work.
R
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Rotating mass is rotating mass. Doesn't matter if it's wheel or tire. A large diameter lightweight racing wheel like a 19" with a slick on it will allow you huge brakes like 15". I'll take that over an 18" wheel with 14" brakes.
Slowing a car down quickly on a road course is almost as important as power to accelerate.
Give me light vehicle weight, gobs of power and monster brakes and I'll be happy!
:thumbsup::coolman::beer:
Bruce - I also did a search for some of the IMSA Grand Touring Prototype cars that I have personally seen down here at the 12 Hours of Sebring and their sidewalls are nowhere near as tall as the F1 car shown on the previous page. Infact they have quite a large staggered wheel set up from what the pictures indicate and a moderate to thinner sidewall. I don't know what size they are (front and rear), but the wheels appear to be large in diameter.
R
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Negative on F1 choosing 13 inch wheels for performance. They run 13 incherS because thats what the rules dictate. Michelin wants to go to 18s if they return to F1 for 2011. So bad example with F1...
I don't know if this is the case now, but back when the 1995 Cobra R was produced with its 17x9's the "raced" cars would have 16's on them, not because 16's performed better, but because that is what the sanctioning race body rules were at that time.
I believe that it was also that way with the 93R.
R
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Rotating mass is not rotating mass. That is incorrect physics.
[ame=http://en.wikipedia.org/wiki/Moment_of_inertia]Moment of inertia - Wikipedia, the free encyclopedia[/ame]
[ame=http://www.5min.com/Video/Calculating-the-Rotational-Inertia-of-Solid-Bodies-174069104]Calculating the rotational inertia of solid bodies Video – 5min.com[/ame]
I know the guy in the video is ridiculous but it shows the point I'm trying to make. Rotational inertia is not just m(mass). It is m * r^2. So if you imagine that all the weight of a rim is in the rim itself and not in the spokes, then an 8"rim of equal weight to a 16" rim would 4 times difficult to spin around an axis. Any function that squares has this sort of effect.
With that said, the construction of the tire also plays a huge role depending on where its mass is located since you can imagine that on the 8" rim there would 8 inches of tire that would have been empty space on the other car.
Point being, location of mass is critical in rotational inertia, not just the mass itself.
As for which one provides the best performance my prior statement was probably pretty hasty. I think we can agree that in a drag set up a large sidewall that can flex will definitely provide the best performance.
I was under the impression, although not from any specific facts that I can point to, that even for road racing it is better to have a small wheel and as much tire as possible, using the compound and sidewall stiffness of the tire to create the desired characteristics of the car.
I think that what size tires exotic manufacturers use is a bad example because they are looking at a mix of style, prestige, and performance to sell to their customers. I thought that race series were a good idea but if their sizes are regulated that doesn't make sense either. If someone could show an authoritiative discussion on teh subject I would definitely appreciate it.
small wheel/big sidewall may be better for maximum potential as far as the numbers go, but a smaller sidewall will give the driver better feel. you can stiffen the sidewall all you want, but it's still made of rubber.
Those are all very good points but MY point was the fact that a smaller diameter wheel with a larger cross section tire is not going to weigh a hell of a lot less than a larger diameter lightweight wheel with a smaller diameter race slick. (read lighweight tire)
To put this in more simplistic terms, let's say we have two 28" diameter wheel and tire combinations. One is a 14" wheel with a taller cross section tire on it and one is a 18" wheel with a shorter cross section tire. Both wheel and tire assemblies weigh 35# EACH! (just for example)
That is why I said rotating mass is rotating mass as long as the two diameters are the same and the weight is the same. Two thin sections of aluminum (wheel) don't weigh anymore than two thin sections of rubber! (tire) :read::idea:
I'm going to choose the 18" wheel because I can fit a 14" brake under it. You can choose the 14" wheel and only fit a 10" brake under it. Guess who's going to be faster on a road course with the same car, same power and same driver?!?! ;-)
oke:Those are all very good points but MY point was the fact that a smaller diameter wheel with a larger cross section tire is not going to weigh a hell of a lot less than a larger diameter lightweight wheel with a smaller diameter race slick. (read lighweight tire)
To put this in more simplistic terms, let's say we have two 28" diameter wheel and tire combinations. One is a 14" wheel with a taller cross section tire on it and one is a 18" wheel with a shorter cross section tire. Both wheel and tire assemblies weigh 35# EACH! (just for example)
That is why I said rotating mass is rotating mass as long as the two diameters are the same and the weight is the same. Two thin sections of aluminum (wheel) don't weigh anymore than two thin sections of rubber! (tire) :read::idea:
I'm going to choose the 18" wheel because I can fit a 14" brake under it. You can choose the 14" wheel and only fit a 10" brake under it. Guess who's going to be faster on a road course with the same car, same power and same driver?!?! ;-)
What I'm saying is that the rotational inertia of the two setups is not the same. Even if they have the same weight and total rim + tire height.
I get that its an advantage to put bigger breaks under the larger rim but I don't think anyone would disagree with that.
+1, I have to side with Chuck and this guy. If your racing 20's aren't the best option. There has been tons of debate and statistical data on this subject, just search TS site / FordGT500 site or any of Bj's comments on this subject.
Have you seen the size of the brakes on the ZR1? GT-R? LP560? Big Brakes = Big wheels, its a legitimate reason.
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