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      06-28-2017, 08:30 AM   #89
yousefnjr
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Quote:
Originally Posted by TSM330i View Post
Other test numbers from Motor Trend:
http://www.motortrend.com/cars/chevr...t-test-review/

I'm not exactly sure why the M4GTS wasn't this quick and cost twice as much.
Street setting bruh. Needs more chin.
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      06-28-2017, 08:54 AM   #90
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Originally Posted by yousefnjr View Post
Street setting bruh. Needs more chin.
Yup if the GTS had its suspension calibrated correctly it would have obviously broken the P1's record on the nurburgring.
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      06-28-2017, 11:13 AM   #91
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http://www.camaro6.com/forums/showthread.php?t=499849
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      06-28-2017, 11:35 AM   #92
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Quote:
Originally Posted by Vigilante375 View Post
Thats what I told to you. Its not the weight of the vehicle but how much power the vehicle has and how effectively you want to get that power to the ground. Weight has nothing to do with it.

You're saying that since the ZL1 weighs so much, that it needs wider tires because of that. No it doesn't. It needs the wider tires to put the power to the ground better and it turns better because of those wider tires.

No one ever looked at a 500hp sports car and said "Hmmm...this car weighs 3000lbs, so I only need 225mm tires."
I can't follow your circle talk. You said forget power. I said so without power we are talking no acceleration. Which means no concerns about traction for acceleration. So we are purely talking lateral handling. And 100% weight is a huge factor in traction and handling. Not only how much weight, but where it is located.

I am sure you have heard the term E = mc^2. In the most basic terms, it means that mass and energy are interchangeable when figuring kinetic energy. Add either weight or speed to a car and the forces intended to break the coefficient of friction of the tire to the road in a lateral movement increase. SO yes, weight is a huge factor is what the tires are able to handle before friction is gone and the tire slips. Obviously is the tire compounds and designs are the same, the increased tire contact patch increases traction. But there are also drawbacks to a larger contact patch. Mainly friction and weight.

If you don't want to believe weight is a factor in how a tire needs to perform, that is fine. I'll stick to know it and use it to my advantage. Good luck.
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      06-28-2017, 02:26 PM   #93
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Originally Posted by 86merc View Post
I can't follow your circle talk. You said forget power. I said so without power we are talking no acceleration. Which means no concerns about traction for acceleration. So we are purely talking lateral handling. And 100% weight is a huge factor in traction and handling. Not only how much weight, but where it is located.

I am sure you have heard the term E = mc^2. In the most basic terms, it means that mass and energy are interchangeable when figuring kinetic energy. Add either weight or speed to a car and the forces intended to break the coefficient of friction of the tire to the road in a lateral movement increase. SO yes, weight is a huge factor is what the tires are able to handle before friction is gone and the tire slips. Obviously is the tire compounds and designs are the same, the increased tire contact patch increases traction. But there are also drawbacks to a larger contact patch. Mainly friction and weight.

If you don't want to believe weight is a factor in how a tire needs to perform, that is fine. I'll stick to know it and use it to my advantage. Good luck.
Where did I say forget power? Unless you're assuming I'm saying forgot about the P1 making the power it makes. No. Do you see the ..... followed after the sentence? That means it's a sarcastic remark.

Understand that weight has nothing to do with determining what size tires you need for a racing/sports/hyper/powerful car.

Look at the tires that hyper cars have, why do you think they have those big tires. Because of the power the car makes. How do they make the a stay planted to the ground when it reaches higher speeds? By adding extra down force by winglets, splitters or a wing. That way the wind will push down on the car to add weight so the car will be firmly planted to the ground.

You know, that cool. Go drive a P1 with 255mm tires all around and see what happens when you go full throttle or race it around a track. Since it does weigh so little.

F1 cars also up'd they're tire size for this season from 325mm rears to the 405mm rears while uping the fronts from 245mm to 305mm for the 2017 season. The car is wider too. Body and chassis.

I don't see where you said "so without power we are talking no acceleration" comment anywhere.

Now if you're talking about straight line accel, weight still isn't an concern. It's still about the power. As I mentioned before, you want to put the power to the ground as efficiently as possible and we'll assume you're suspension/drivetrain is already setup properly. So now choose a proper sized tire for the power you're making. Would you want a 245mm rear tire when you're pushing 650rwhp since you're car only weighs 3100lbs? No. You'd want start with a 275mm tire and then try a different tire if you spin too much.

You'll actually be surprised at how many cars run 275s while making 600+rwhp and weigh over 3600lbs. Though they may be on barely street legal tires or actually slicks. Like 2nd gen CTS-V's, 03-04 Cobras, GT500s, Hellcats, etc.
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      06-28-2017, 02:56 PM   #94
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The fact you can't even imagine weight being a factor in how a car performs, or it's equipment requirements, tells me I should just stop and leave this alone. It's not worth arguing with you if you are not open minded or wanting to learn.

But since you mentioned 650 hp cars with a 275 width tire I'll give you a little background on me. About 6-8 years ago I had a full blown street car that made 950-1,100 hp to the tire. It was just shy of 4000 lbs. with me in the car. With the wrong converter in the car, I still managed to run 1.32 60' times on 17" street wheels all the way around and a 255 width contact patch tire. I can tell you weight was a huge reason I could get the car to hook so well. You can apply a lot of downward force with all that weight. I won't even get started on the MX235 drag class that my buddies run. They are limited to a 235 width tire yet run mid 4's at 150+ mph in the 1/8th. Some are obviously able to do more with less. I'm not a newb to drag racing and road racing. But I am always learning from testing and talking to others.



Anyways, good luck with your beliefs.
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      06-28-2017, 03:24 PM   #95
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Traction is pretty hard without mass as the csr would be able to float. Drag car uses weight shift to add mass. Race car used aero to add mass in the form of downforce without the repercussions of actual weight.
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      06-28-2017, 03:29 PM   #96
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Exactly. Faster drag cars use aero and downforce as well. The wings out back help keep the car & tires planted at speed. And Aero keeps the air from under the car as to not have the air under the car lift the car. No one likes taking off on a drag pass. haha

So drag car use aero just as road course cars do.
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      06-28-2017, 08:51 PM   #97
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Quote:
Originally Posted by 86merc View Post
The fact you can't even imagine weight being a factor in how a car performs, or it's equipment requirements, tells me I should just stop and leave this alone. It's not worth arguing with you if you are not open minded or wanting to learn.

But since you mentioned 650 hp cars with a 275 width tire I'll give you a little background on me. About 6-8 years ago I had a full blown street car that made 950-1,100 hp to the tire. It was just shy of 4000 lbs. with me in the car. With the wrong converter in the car, I still managed to run 1.32 60' times on 17" street wheels all the way around and a 255 width contact patch tire. I can tell you weight was a huge reason I could get the car to hook so well. You can apply a lot of downward force with all that weight. I won't even get started on the MX235 drag class that my buddies run. They are limited to a 235 width tire yet run mid 4's at 150+ mph in the 1/8th. Some are obviously able to do more with less. I'm not a newb to drag racing and road racing. But I am always learning from testing and talking to others.



Anyways, good luck with your beliefs.
Ok, so now you're going back on what you originally said so I'm backing out since you're going in circles now......
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      06-29-2017, 10:49 AM   #98
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Whatever you say. lol
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      06-29-2017, 12:09 PM   #99
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Originally Posted by 86merc View Post



Whatever you say. lol
Alright so. Look at this. You first say weight is the reason why the Camaro needs the wide tires. What you're saying is that any heavy vehicles needs wide tires because it weighs so much. Not because of the power it's making.

That means a 10000 hp top fuel car doesn't need the tire setup it currently has. They should be using a smaller tire since it weighs so little. This is the assumption I get that YOU are saying.
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      06-29-2017, 12:30 PM   #100
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I said the power and weight are part of it. YOU said weight has nothing to do with it.

You don't get the points made, you don't understand it the physics involved, and make assumptions that are not correct. I am done addressing it.
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      06-29-2017, 02:03 PM   #101
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Power, weight, grip, and to a lesser extent drag, make a laptime. Handling is optional, although I bet this car probably handles pretty well.

Re: the discussion above, the reason the car uses really fat tires is because for a given weight and power level, that allows them to use a softer compound without destroying it. You could use 2 inch wide tires made from the same compound, and they would have a very similar grip until the point they overheat / the car tears them apart which would probably happen immediately.
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      06-29-2017, 02:24 PM   #102
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Quote:
Originally Posted by 86merc View Post
I said the power and weight are part of it. YOU said weight has nothing to do with it.

You don't get the points made, you don't understand it the physics involved, and make assumptions that are not correct. I am done addressing it.
And you say power has nothing to do with it. I understand the physics involved but I am certain people never assume you need a wider tire because a car weighs so much. The main reason is because of the power its making.

You never said power anything about power. You've only talked about weight.

I say power has a big part of it and weight is never the factor for choosing a tire size.

You obviously are set in your ways so I'll continue choosing tires for the power they are making and the amount of grip I want for handling while you can choose tires solely for their weight.
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      06-29-2017, 03:41 PM   #103
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Will you two children please stop
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      06-29-2017, 03:42 PM   #104
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Will you two children please stop
Haha, it's slow around here. Let them carry on.
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      06-29-2017, 06:54 PM   #105
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Motortrend and a bunch of other media guys came to my local track (Area27) to test the ZL1 1LE and it kicked fucking ass.

Randy was able to pull off a 2:11.88 on this monster track and for reference, the official time set by a 675LT was 2:10.40 and an ACR did it in 2:09, bone stock, both driven by professional race car drivers. GT3 RS's have posted 2:13s and the fastest Radical has just broken 2 minutes.

http://www.motortrend.com/cars/chevr...t-test-review/

For just about $73k usd, this thing is definitely the best bang for the buck. I have so much respect for this machine and its value.

Last edited by Nkc; 06-30-2017 at 12:12 AM..
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      06-29-2017, 07:03 PM   #106
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Will you two children please stop

I keep trying!
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      06-30-2017, 04:42 PM   #107
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86 and Vig must have missed the part where I accurately distilled track performance down to as few criteria as possible AND explained wide tires in a way that hopefully makes sense. See my previous post, and if you have any questions, we can have an intelligent adult discussion about it. ��

Quote:
Originally Posted by The Wind Breezes View Post
Power, weight, grip, and to a lesser extent drag, make a laptime. Handling is optional, although I bet this car probably handles pretty well.

Re: the discussion above, the reason the car uses really fat tires is because for a given weight and power level, that allows them to use a softer compound without destroying it. You could use 2 inch wide tires made from the same compound, and they would have a very similar grip until the point they overheat / the car tears them apart which would probably happen immediately.
To expand on the tire thing, you have two main components to tire grip. Classical friction, which is mostly* independent of surface area, and mechanical keying, which does depend to some extent on surface area. Mechanical keying is where the little bits of rubber actually interlock with the rough tarmac. This goes away when there's water on the surface because the little bits that would deform into the rough terrain actually micro-hydroplane and you're left with classical friction. That's why, other things equal, peak rain grip usually isn't far off peak dry grip, but continuity and progressive loss of grip are really reduced. Both classical friction and mechanical keying will increase with the softness of your tire compound. Of course, it's easy to imagine how as you make a compound softer, its resistance to mechanical abuse is reduced, so you need MORE of it to spread out a given mechanical stress, reducing mechanical strain in heavier or more powerful cars. That's the main reason why cars like this Camaro use really big tires, so they can run a softer compound for good grip without chunking or overheating it after a short time.

*This is because coefficient of friction will increase the less loaded a given piece of rubber is, but to really take advantage of this, you either need tires with an impractically big contact area, OR a really light vehicle.

Last edited by The Wind Breezes; 06-30-2017 at 04:54 PM..
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      07-03-2017, 09:41 PM   #108
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So, about dat ZL1 1LE doh.....

I'd fancy a black one. Told myself I wouldn't get another black car, but the zl1 looks too good in black.
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      08-30-2017, 09:00 PM   #109
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It goes well. But like all American cars there's a reason that it's cheap. You have to put up with NVH that is far inferior to European equivalents and an interior made out of old dustbin lids
How many American cars have you driven from this century? I find that the quality of them is getting closer and closer to on par every year. Germans are getting lazy and Americans are stepping up to the plate.
Full disclosure. I work for an American auto company.
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      08-31-2017, 08:35 AM   #110
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Originally Posted by Ngilbe36 View Post
How many American cars have you driven from this century? I find that the quality of them is getting closer and closer to on par every year. Germans are getting lazy and Americans are stepping up to the plate.
Full disclosure. I work for an American auto company.
Ha. I also happen to work for an american auto company..... I agree with this statement. There's just nothing that can compare to the GM performance cars for the money right now. It's not even close.

Last edited by HawkeyeGeoff; 08-31-2017 at 11:22 AM..
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