LOL.....ZL1 owners facing traction issues

[cgouzoulis]

lets also not forget another MAJOR factor of these conditions.... IAT's are much lower in the winter time, therefor were making more power...engine runs cooler cause computers to pull less timing. Its almost a give and take....more top end in winter, more hook in summer

 

[R1Lello]

I think "traction control" will prove to be a big disappointment for both the ZL1 and the GT500.

I reality, all traction control is, is "torque limiting".

As pointed out in this thread, the laws of physics must be obeyed. Unfortunately that means wheel spin.The vettes will have it better because they have a better static weight distribution, but blown pony cars are nose heavy.

Bingo ! :beer:

 

[R1Lello]

This. It's moronic to say "My car has traction problems in 40* weather on goodyears!" Guarantee that when it's 85* in Florida-type humidity the car won't even spin the tires from a roll out.

I'm agreeing with you, higher temps. def'ly will be much better for sure:beer:

 

[DBK]

I'm agreeing with you, higher temps. def'ly will be much better for sure:beer:

I know, I'm agreeing with you too. I'm saying anyone that feels the need to say "My car has traction problems!" when the only conditions they've driven in are 40* weather doesn't know much about fast cars with factory tires.

 

[300AGT]

Graagelogic

I've been driving summer tires year round on my GT500's since 2007 and I could not disagree more. They have better traction when it is warm, no doubt, but never have they been able to "dead hook" in first or second gear, roll or not.

I don't drive a GT500 i got a 2011GT dosen't apply power the same way a GT500 dose that i didn't by one.

 

[Ry_Trapp0]

I think "traction control" will prove to be a big disappointment for both the ZL1 and the GT500.

I reality, all traction control is, is "torque limiting".

As pointed out in this thread, the laws of physics must be obeyed. Unfortunately that means wheel spin.

The vettes will have it better because they have a better static weight distribution, but blown pony cars are nose heavy.

disagree. the traction control in these cars will be as good as the amount of time they spent on them. it could be as shitty as what's found in a cheby cobalt, or as good as is used on lemans prototypes. they all work the same way, but how good they work is purely dependent on the amount of time spent tuning it(parts dependent as well of course, i'm sure LMPs have wheel speed sensors reading at a much higher resolution than that found on a cheby cobalt).

if you want to see quality traction control, the AMG and M series cars are on a completely different level than any previous "big 3" offerings. hopefully the '13 GT500 and the ZL1 are stepping it up into that territory. no one should be disappointed in that case.

 

[Mr.Bolt-on]

Tire compound plays a bigger role in traction issues than tire width... unfortunately so many people think that just because you have a wider tire means that you'll automatically get more traction.

 

[Ry_Trapp0]

Tire compound plays a bigger role in traction issues than tire width... unfortunately so many people think that just because you have a wider tire means that you'll automatically get more traction.

pretty interesting piece on this from a guy with a turbo '66 mustang in hotrod mag...

Q: For us non-physics guys, please explain F=uN.

A: F, the forward force that accelerates your car, is the product of "u", which is the traction coefficient for a given pair of materials (in this case rubber on asphalt) times the "downforce" ("N") of the drive wheels on the road. The width of the tire is never in this calculation. The only reason wider tires can help is they can increase the "effective u" just a little, not a lot.

Wide tires are far more "show" than "go," no matter how much our egos want to disagree with that. The bottom line is g’s, and we’ve done a lot of testing in this area. The data should speak for itself, and correspond to tests on the street. Track conditions are typically better. The lowest traction limits we’ve measured are all on front-wheel-drive cars. This is because of the weight transfer offthe drive wheels when accelerating. They’re always between .40g and .50g.

Rear-wheel drive vehicles fare better. Most pickup trucks generate between .48 and .52g, thanks to in-optimized weight distribution. Non-posi cars are again a little better. They typically generate a maximum of .50 to .55g almost every time. We tested a Ford Crown Victoria with 215mm rubber, and it would spin the right rear at .50g. Next test was a ‘66 Mustang Coupe with 195mm rubber, which spun ‘em at .53g. A Volvo wagon (195mm tires) spins the right rear at .55g. This Mustang Fastback, with a posi and BFG radial T/A tires (215 mm) pulled .54g before the changes, and with the battery in the trunk now pulls .55 to .56g. Grand National Buicks (with posi) usually got .55g, 5.0L Mustangs (225mm, with posi) get .56 to .59g. My friend Rich has a ‘69 Super Bee, good posi, 215mm BFG’s, and pulls .57g before they spin. Note that these are not big differences from the best to the worst!

Now for some wide tire data: my friend John has a ’66 Nova with 275mm rubber and a good posi, yet it pulls .53 g max, right in there with my skinny-tired ’66 Mustang. Rich also owns a Hemi Charger with 275mm rubber, which can’t generate more than .55g, which you’ll note is less than his Super Bee does on 215s. That’s because he has played the weight distribution game on the Super Bee.

Highest street tire numbers ever? Weight distribution is a player. New Z28s (245 mm) commonly pull .62g max. My friend Shirl has a ‘79 Corvette (245 mm) pulls .65g on street tires.

See where I’m going here? There’s no magic "factor of two" yet. Honestly, even a posi only seems worth .05g or so (10 percent). How many guys do we run into that think a posi will double their traction?

Want to see big improvements? Change the tire compound. My friend Dave bought some BFG Drag Radials for his 5.0L Mustang. His 225mm street tires spin at .59g every time, yet his 235mm Drag Radials consistently pulled .68g. That’s 15 percent! A co-worker brought in his NSX with 245mm race tires, and thanks to the combined help of its mid-engine layout, we were measuring .75 g launches, over and over again!

I’m not saying that wider tires would hurt, I’m just arguing that they’re far more for show than go. They wouldn’t double the traction. Or add 50 percent, or even 25 percent. The max we’re talking is probably under 10 percent. So without tubbing the car, I can probably squeak in some 245mm tires if I had to. By trying to play the testosterone factor low on this car, my best money will go towards a set of drag radials, and selectively moving weight to the rear, not tubbing the car and running 315mm street tires.

Q: What's the big deal about g's on launch?

A: G's are inversely proportional to velocity. What that means is that peak g's occur at very low speeds and continue to drop as speed goes up. When we're talking traction limits, we're talking peak g's, and by definition, they happen at launch or soon after when hitting the torque peak in low, if gearing is not optimized. So when you want to talk tires, or traction limits, you talk g's on launch.

Of course g's on launch are everything to guys who only think about e.t. Blowing the launch kills e.t. Blowing the last 300 feet of the track kills trap speed. In a related sense when you want to discuss power, you tend to discuss g's at some higher speed, because, let's face it, even a Corolla can pull .50 g at 2 mph and chirp the tires. And a Hemi Charger can pull .55g at 2 mph—which doesn't look like much of an advantage! But, by 30, 40, 50 mph, the Corolla's low power/weight ratio has g's plummeting down, so it’s only pulling .20 g at 30, while the Charger can still spin 'em at .55g at 30. Why? It had the power to pull 1.0 or more g at 2 mph, but thanks to tires was limited to the .55 g level. At the track, the Mustang consistently pulls .70g at 60 mph. This makes it clear why, on the street where the traction limit is more like .55g, the car will spin the rear tires at speeds below 70 mph.​

Turbo Tech - Questions And Answers - Supercharger Comparison - Hot Rod

their website puts some strange character in place of apostrophes for whatever reason.

 

[thePill]

pretty interesting piece on this from a guy with a turbo '66 mustang in hotrod mag...

Q: For us non-physics guys, please explain F=uN.

A: F, the forward force that accelerates your car, is the product of "u", which is the traction coefficient for a given pair of materials (in this case rubber on asphalt) times the "downforce" ("N") of the drive wheels on the road. The width of the tire is never in this calculation. The only reason wider tires can help is they can increase the "effective u" just a little, not a lot.

Wide tires are far more "show" than "go," no matter how much our egos want to disagree with that. The bottom line is g’s, and we’ve done a lot of testing in this area. The data should speak for itself, and correspond to tests on the street. Track conditions are typically better. The lowest traction limits we’ve measured are all on front-wheel-drive cars. This is because of the weight transfer offthe drive wheels when accelerating. They’re always between .40g and .50g.

Rear-wheel drive vehicles fare better. Most pickup trucks generate between .48 and .52g, thanks to in-optimized weight distribution. Non-posi cars are again a little better. They typically generate a maximum of .50 to .55g almost every time. We tested a Ford Crown Victoria with 215mm rubber, and it would spin the right rear at .50g. Next test was a ‘66 Mustang Coupe with 195mm rubber, which spun ‘em at .53g. A Volvo wagon (195mm tires) spins the right rear at .55g. This Mustang Fastback, with a posi and BFG radial T/A tires (215 mm) pulled .54g before the changes, and with the battery in the trunk now pulls .55 to .56g. Grand National Buicks (with posi) usually got .55g, 5.0L Mustangs (225mm, with posi) get .56 to .59g. My friend Rich has a ‘69 Super Bee, good posi, 215mm BFG’s, and pulls .57g before they spin. Note that these are not big differences from the best to the worst!

Now for some wide tire data: my friend John has a ’66 Nova with 275mm rubber and a good posi, yet it pulls .53 g max, right in there with my skinny-tired ’66 Mustang. Rich also owns a Hemi Charger with 275mm rubber, which can’t generate more than .55g, which you’ll note is less than his Super Bee does on 215s. That’s because he has played the weight distribution game on the Super Bee.

Highest street tire numbers ever? Weight distribution is a player. New Z28s (245 mm) commonly pull .62g max. My friend Shirl has a ‘79 Corvette (245 mm) pulls .65g on street tires.

See where I’m going here? There’s no magic "factor of two" yet. Honestly, even a posi only seems worth .05g or so (10 percent). How many guys do we run into that think a posi will double their traction?

Want to see big improvements? Change the tire compound. My friend Dave bought some BFG Drag Radials for his 5.0L Mustang. His 225mm street tires spin at .59g every time, yet his 235mm Drag Radials consistently pulled .68g. That’s 15 percent! A co-worker brought in his NSX with 245mm race tires, and thanks to the combined help of its mid-engine layout, we were measuring .75 g launches, over and over again!

I’m not saying that wider tires would hurt, I’m just arguing that they’re far more for show than go. They wouldn’t double the traction. Or add 50 percent, or even 25 percent. The max we’re talking is probably under 10 percent. So without tubbing the car, I can probably squeak in some 245mm tires if I had to. By trying to play the testosterone factor low on this car, my best money will go towards a set of drag radials, and selectively moving weight to the rear, not tubbing the car and running 315mm street tires.

Q: What's the big deal about g's on launch?

A: G's are inversely proportional to velocity. What that means is that peak g's occur at very low speeds and continue to drop as speed goes up. When we're talking traction limits, we're talking peak g's, and by definition, they happen at launch or soon after when hitting the torque peak in low, if gearing is not optimized. So when you want to talk tires, or traction limits, you talk g's on launch.

Of course g's on launch are everything to guys who only think about e.t. Blowing the launch kills e.t. Blowing the last 300 feet of the track kills trap speed. In a related sense when you want to discuss power, you tend to discuss g's at some higher speed, because, let's face it, even a Corolla can pull .50 g at 2 mph and chirp the tires. And a Hemi Charger can pull .55g at 2 mph—which doesn't look like much of an advantage! But, by 30, 40, 50 mph, the Corolla's low power/weight ratio has g's plummeting down, so it’s only pulling .20 g at 30, while the Charger can still spin 'em at .55g at 30. Why? It had the power to pull 1.0 or more g at 2 mph, but thanks to tires was limited to the .55 g level. At the track, the Mustang consistently pulls .70g at 60 mph. This makes it clear why, on the street where the traction limit is more like .55g, the car will spin the rear tires at speeds below 70 mph.​

Turbo Tech - Questions And Answers - Supercharger Comparison - Hot Rod

their website puts some strange character in place of apostrophes for whatever reason.

Lots of good info here...

 

[Drwalker02]

Lots of incorrect info.

F=uN. F is the force of friction and is the product of the coefficient of friction u ( determined based on the properties of the two contacting surfaces) and N which is the Normal force or mass x gravity of the part of downward force that is perpendicular to the surface. But Normal force is also related to tire size in that the footprint pressure is greater in smaller areas than larger areas with a same weight or mass, similar to a snowshoe vs regular shoe in the snow

In the case of this frictional force, there are actually two types, rolling and static friction. All that equation gives is the force required to move and object. The force must overcome F. If your acceleration generates more force than the tire/ground interface can handle, your tires spin, slide, skid, whatever.

Secondly, the contact area between two surfaces plays a large role in traction, but also requires more spinning force to overcome. It's simply a double edged sword.

Increasing downward force does increase your Normal force (N) and thus increasing down force helps maintain traction

I think it's a little oversimplified.

 

[SVTDice]

Us Terminator guys don't need damn Traction control. No, But seriously. We don't. If you need traction control to hook in 2nd and even 3rd gear? Theres something wrong with your either. A. Tires, B. Suspension setup. C. Both.

On a "Warmer" Day I can dead hook in 2nd and 3rd. (With over 500RWHP to the TIRE) Sig numbers are old. On a colder only a bit of spin. Even though I'm running 3.55's for the rear end. Instead of 3.73's. But honestly, I'm no expert. Its just my .02 cents. GM needs to look into wider tires, more aggressive suspension setup and so on and so forth.

 

[95SC]

Us Terminator guys don't need damn Traction control. No, But seriously. We don't. If you need traction control to hook in 2nd and even 3rd gear? Theres something wrong with your either. A. Tires, B. Suspension setup. C. Both.

There is definitely something wrong with my terminator because it brakes 335 hoosier drag radials at 60 mph .i'd love to have good quality traction control on the car

 

[SVTDice]

There is definitely something wrong with my terminator because it brakes 335 hoosier drag radials at 60 mph .i'd love to have good quality traction control on the car

Sadly, If its the one in your signature almost having twice the HP as me. That is ALOT of power to put down. You may need to go with even wider tires, or taller ones. 28's perhaps? What do you have for a suspension setup? Full IRS Bushings? If not Full tilt boogie racing has a very good set that you may wanna look into. Possibly looking into coil overs as well but I'm not sure how well coil overs do for traction for that amount of power.

 

[Ry_Trapp0]

Lots of incorrect info.

F=uN. F is the force of friction and is the product of the coefficient of friction u ( determined based on the properties of the two contacting surfaces) and N which is the Normal force or mass x gravity of the part of downward force that is perpendicular to the surface. But Normal force is also related to tire size in that the footprint pressure is greater in smaller areas than larger areas with a same weight or mass, similar to a snowshoe vs regular shoe in the snow

In the case of this frictional force, there are actually two types, rolling and static friction. All that equation gives is the force required to move and object. The force must overcome F. If your acceleration generates more force than the tire/ground interface can handle, your tires spin, slide, skid, whatever.

Secondly, the contact area between two surfaces plays a large role in traction, but also requires more spinning force to overcome. It's simply a double edged sword.

Increasing downward force does increase your Normal force (N) and thus increasing down force helps maintain traction

I think it's a little oversimplified.

look at the article, it's just a quick Q&A. this wasn't a multi page college physics lesson, just a simplification(like you said) to prove a point. point being that tire compound and weight distribution play VERY significant roles and tire width is a comparatively minor role.

 

[Drwalker02]

look at the article, it's just a quick Q&A. this wasn't a multi page college physics lesson, just a simplification(like you said) to prove a point. point being that tire compound and weight distribution play VERY significant roles and tire width is a comparatively minor role.

I understand, but he flat out screwed up. The F he mentioned is never intended to represent forward force when used n that context. Makes everything he said less believable

 

[Ry_Trapp0]

ah, i gotcha.

 

[jtfx6552]

disagree. the traction control in these cars will be as good as the amount of time they spent on them. it could be as shitty as what's found in a cheby cobalt, or as good as is used on lemans prototypes. they all work the same way, but how good they work is purely dependent on the amount of time spent tuning it(parts dependent as well of course, i'm sure LMPs have wheel speed sensors reading at a much higher resolution than that found on a cheby cobalt).

if you want to see quality traction control, the AMG and M series cars are on a completely different level than any previous "big 3" offerings. hopefully the '13 GT500 and the ZL1 are stepping it up into that territory. no one should be disappointed in that case.

Disagree with what? Traction control limits torque to the tires, IT DOES NOT ENHANCE TRACTION AT ALL!

 

[ON D BIT]

Disagree with what? Traction control limits torque to the tires, IT DOES NOT ENHANCE TRACTION AT ALL!

So one can not limit torque in order to create traction? It seems this is exactly what Ford did as it took a great driver all day at the strip to recreate the same results as the traction control/launch management system did on the very first run!oke:

 

[jtfx6552]

In Physics 101, the frictional force is uN,, the coefficient of friction and the force perpendicular to the surface, that is it, there is no factor for surface area. So if you have two steel plates against one another, the weight of the top plate times the coefficient of friction is the force required to slide the plate, it doesn't matter if the plate is 1" x 1", or 1' x 1', the force is the same if the weight and coefficient of friction are the same.

Clearly, tires do not behave like steel plates, and surface area matters.

Having said that, one of the most common misconceptions is that wider tires put more surface area on the ground, this is not true. Read it twice, three times, as many times as you want.

With a conventional non run flat tire, with an insignificantly stiff sidewall, the tire patch area is the weight on the tire, divided by the air pressure in the tire.

If the back rh corner of the car weighs 800 lbs, then the area on the ground at 20 psi is 40 square inches, doesn't matter if it is a 335/35 or a 185 70, the area is the same, albeit different shape. Granted, a larger wheel and tire may allow lower pressure before the rim hits the ground, but for all practical purposes the area is the same.

The real brain twister is, according to tire designers, the longer the pattern in the direction you are trying to generate traction, the better. What does that mean? Well, for acceleration, theoretically you'd want a long narrow patch For cornering you'd want a wide short patch. Doesn't match well with conventional drag strip wisdom...

 

[jtfx6552]

So one can not limit torque in order to create traction? It seems this is exactly what Ford did as it took a great driver all day at the strip to recreate the same results as the traction control/launch management system did on the very first run!oke:

No, you can not limit torque to create traction. Best that can be done is keep the tires on the edge of slip, but at the end of the day, there was no "extra" traction created, just the available traction used.

I see this quote repeated often "as it took a great driver all day at the strip to recreate the same results as the traction control/launch management system did on the very first run!", anyone have the original reference?