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19's front - 20's rear ...?

Garcia172

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Nobody's talking about those cars.

and you're running the same size front and rear. So again what's your point?
The point.. which is all in response to your reply implying that I was some hidden LLM keyboard jockey spamming the forum with "drivel". So I had to spell it out to you and show you real-life pictures to back up what I'm saying.

Again...

There is a big advantage of having larger diameter rear tires on the race track. What's learned in racing trickles down to street cars, as evidenced by GM, Porsche, Lambos, & Ferrari applying the same concepts.

You're not getting it. Yes in this example (a real race car I raced) they are both 18" rims. Because the tire manufacture, Michelin, only makes these in 18". If they made them in larger sizes, we would be running larger sizes. So they make them taller to comply with the rules (which is effectively the same as making them bigger in diameter). Hello....

The OEM's can use bigger rear diameter rims because you can get the street tires in larger diameter.... which they in fact do so. And they understand that the same concepts in racing apply to high performance street cars. Which is why they do so. Which I articulated previously.

Again... there is a clear advantage to using a bigger diameter rear tiers and I articulated that through quoting LLM (to save time) and explaining it to you in my own words (so as to not drivel).

You shouldn't argue things you know nothing about (referring to road racing setup).

Go look at every manufactures factory GT3 race cars and you'll see the same taller (larger diameter) rear tires... there's a reason why.
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robvas

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Nobody was asking about the generic advantage of larger wheels. We are all aware of what they are.

I specially said what's the point of doing what he wanted to do.

I was expecting something like "I like the looks of it" or "I want to run XYZ tire that comes in this size."
 

Garcia172

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Nobody was asking about the generic advantage of larger wheels. We are all aware of what they are.

I specially said what's the point of doing what he wanted to do.

I was expecting something like "I like the looks of it" or "I want to run XYZ tire that comes in this size."
You asked "what's the advantage".

I answered by quoting LLM (because it was faster).

You accused me of using LLM to spew drivel and spam the forum.

So I articulated the advantages in my words, and used photos to show you how it's done in real racing and why... and showed you that the OEM's do the same thing for the same reasons.

That's how we got here.

And for the record, I did say that for me, on the S650 it's an aesthetics thing that the car need a bit of rake and the way to do it was to use the larger rear wheels to keep the wheel-to-fender gaps the same.
 

Dave2013M3

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Guess Ferrari is Ghetto lol
The list is much larger. Personally, I like the look. The car could use a slight rake. This allows you to get the same tire-to-fender gap, but with the slight almost unnoticeable rake.

But you can cry about LLM, but it is a fact Jack... :-) Go look at factory Porsche Cup cars as an easy example... while the rim diameter is the same, the rear Michelin slicks are much much taller and bigger in diameter (710's) than the front. I know because I've raced them for many years.

As far as OEM street cars go.... I guess GM(Corvette), Ferrari, Lambo, & Porsche (Street cars) don't know what they're doing but you do. Got it.

Don't forget that BMW M cars have larger wheels in back as well.
 

Garcia172

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Nobody was asking about the generic advantage of larger wheels. We are all aware of what they are.
Who is "we"? You? Are you the elected representative on this forum? Oh... you know what everybody here knows and doesn't know? Really?

You might learn something if you weren't so arrogant.
 


Garcia172

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Don't forget that BMW M cars have larger wheels in back as well.
Lol... yep. BMW M's are amazing performance cars..... There's a reason why. So much is learned from the race track that trickles down into production street cars. The larger rears are just one of many...
 

robvas

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And those BMWs would never, ever go with 18 or 19's all around when they actually go to the race track...

Ford missed out on putting 21's on the back of the GTD. Better call them up. Would probably have beat the ZR1 if they used them.
 

Garcia172

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And those BMWs would never, ever go with 18 or 19's all around when they actually go to the race track...

Ford missed out on putting 21's on the back of the GTD. Better call them up. Would probably have beat the ZR1 if they used them.
Because the Michelin blue slicks come in 18" primarily.. which is what they are running on the track.

The the rear tires (710) are so much taller than the fronts... it's like running a 2" bigger wheel diameter.

The GTD is a street car not legal to run in any professional class of racing. It's an expensive street/track day toy... not running slicks.

... which is why Ford is coming out with a new GT3 race car. And watch which tire they'll be running :-)
 

robvas

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Dark Horse R runs 18x11" front and rear. Would they gain anything by going with a 19x11 or 20x11?

So why don't Michelin/Hoosier come out with bigger slicks? If they're faster racers should want to use them, they will take any advantage they will get.

Is it worth going to a heavier, larger wheel?
So why
The GTD is a street car not legal to run in any professional class of racing. It's an expensive street/track day toy... not running slicks.
Perfect. No excuse to not go with a larger rear wheel than front then.
What's learned in racing trickles down to street cars, as evidenced by GM, Porsche, Lambos, & Ferrari applying the same concepts.
You also have to remember that expensive sports cars are driven by looks as much as anything else. You can't have a big old sidewall on a Ferrari or Lambo. It wouldn't look right. So you have to go to a large diameter (20+) wheel to get the desired tire height.

Can you honestly say that a Michelin/Pirelli high performance tire is going to be any faster on a 305/30-20 vs a 305/35-19?
 

Garcia172

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Dark Horse R runs 18x11" front and rear. Would they gain anything by going with a 19x11 or 20x11?

So why don't Michelin/Hoosier come out with bigger slicks? If they're faster racers should want to use them, they will take any advantage they will get.

Is it worth going to a heavier, larger wheel?
So why

Perfect. No excuse to not go with a larger rear wheel than front then.

You also have to remember that expensive sports cars are driven by looks as much as anything else. You can't have a big old sidewall on a Ferrari or Lambo. It wouldn't look right. So you have to go to a large diameter (20+) wheel to get the desired tire height.

Can you honestly say that a Michelin/Pirelli high performance tire is going to be any faster on a 305/30-20 vs a 305/35-19?
Listen you asked the reason why and I answered. This is not opinion it's fact.

I haven't done any track time testing side by side to answer the question, but it's very clear why manufacturers do this.

If you read the LLM , the drivel spamming the forum I posted, then you know what the answer is.

For me an s650 it's aesthetics. Which also plays into every manufacturer decision if you read the initial post I driveled about. Go back and reread it.

What is learned on the race track trickles down into production cars especially high-end production cars. Which, aesthetic aside, is why you see them on so many high performance cars.

I'm not sure what the big deal is but there is a reason why whether you believe it or not. It's clear you don't have any high-end road racing experience otherwise this conversation wouldn't be happening.

When you take your race car car on a track and learn how to drive it at 10/10ths racing, lap , after lap for hours, against very fast cars on very fast tracks, against outstanding drivers, and have lots of wins and podium finishes...come talk to me.

So don't put 20 inch wheels on your car whatever.

To answer your question about Michelin slicks... They're about $3,000 a set and we go through four sets on a weekend. Each is good for 30 to 45 minutes max before the rubber starts to get hard and the cars slow down. Think about the business aspect of making these tires. You think they're really going to make them in a million different sizes?

On top of that, series are always trying to equalize the cars... Typically powered weight ratio.... Having a standard tire size is one way.
 
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robvas

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Listen you asked the reason why and I answered. This is not opinion it's fact.

I haven't done any track time testing side by side to answer the question

If you read the LLM then you know what the answer is.


When you take your race car car on a track and learn how to drive it at 10/10ths racing, lap , after lap for hours, against very fast cars on very fast tracks, against outstanding drivers, and have lots of wins and podium finishes...come talk to me.
So you don't use them, and You never tested them but they're faster because the LLm said so

Got it.

It's common knowledge that a larger wheel is going to perform better to a certain point. But the stupid LLM doesn't know that. Donks should be winning road races.
 
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Garcia172

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So you don't use them, and You never tested them but they're faster because the LLm said so

Got it.
You don't need to use them to understand the differences between a car that has a bigger circumference tires and the way it deals with heat and the one with the smaller circumference and the way they deal with heat.

What you saying is silly as if somebody needs test every single tire, back to back, same circumference tire front / rear vs different circumference tires front/rear... on a racetrack, in order argue well documented facts.

You sound desperate trying to make your ridiculous argument. Seriously. Like a rookie lawyer trying to cross examine....

I'm sure the engineers at BMW Ferrari Porsche Lamborghini etc... would be laughing at your ignorance if they read this.

What's this thing again? "Ignorance is bliss"?

Is this you speaking or is this you representing everybody ... "We" or "everybody" again?

You sound like a keyboard jockey with a zero experience arguing something you clearly know nothing about.

If you're online ego didn't get in the way you might actually learn something from people that actually have done this over and over for many years with many wins.

This whole thing has been taken on this tangent that really is kind of ridiculous. If you don't like 20 inch tires on a s650 don't put them on. Who cares.

I've been clear about why I, (and apparently others) am interested in doing the f/r staggered diameters.

Is that okay with you?
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