loose control under acceleration?

[Steve Schneider]

I'm little miffed how good experienced drivers can loose control of these cars under acceleration, I have owned high horse vehicles and mainly keep wheels straight with warm tires, dry hot and have pushed my GT spinning tires and been OK? Is it more power than I think or is the GT a little unpredictable? my other cars are big block just as quick, can this thing wind up that much faster higher rpm causing spinning? I'm over careful now, especially when I just heard a crown in the road or a small stone can cause this. Any thoughts? prefer not to crash cause I still want the exhilaration

Steve

 

[Kayvan]

Ambient Temperatures play a huge role

Goodyear Supercar F1s are summer tires and compound is just not designed for Temps <50

During summer you will be fine; see other posts on tires/warm up

 

[HHGT]

Mid Engine Cars and Physics have much to do with vehicle dynamics.

 

[JAYGT]

Its more of a mid engine design and a smooth power delivery. It doesn't feel like your hanging it out that much but you really are, and the other big factor is the tires. Alot of people are used to big power front engined rear wheel drive cars and used to the characteristics of how that platform brakes loose under power.

Damn just noticed that HHGT beat me to it. LOL:ack

 

[SteveA]

I've noticed the GY F-1's on both my zo6 and GT got hard/greasy with multiple heat cycles and age. Both cars would do hellacious first gear roll-on burn outs when the tires still had plenty of tread left but were more than a few years old. My father had the same year zo6 as I and it was so noticeable he believed his car was getting faster and faster as the motor "broke in" . Boy was he sad when I got him a new set of tires.:lol

 

[cobra498]

I'm little miffed how good experienced drivers can loose control of these cars under acceleration, I have owned high horse vehicles and mainly keep wheels straight with warm tires, dry hot and have pushed my GT spinning tires and been OK? Is it more power than I think or is the GT a little unpredictable? my other cars are big block just as quick, can this thing wind up that much faster higher rpm causing spinning? I'm over careful now, especially when I just heard a crown in the road or a small stone can cause this. Any thoughts? prefer not to crash cause I still want the exhilaration

Steve

I would say it is more of a driver skill/experience problem than anything else, the car is very stable when you consider the power to weight. An experienced driver will evaluate the available grip with moderate throttle application and then determine how much throttle is appropriate for the available grip. Just mashing the throttle is an invitation for a loss of control especially in cold weather where the engine is making 50-75 more horse power and the tires have even less grip. A race car and I don't mean some track day special, is very unstable for about a lap or two and would spin out in a heart beat if the driver just wacked the throttle open, why would a GT driving down the street on cold tires be any different? The whole problem in a nut shell is how quickly and how far the throttle is opened, treat it with respect and you won't have a problem.

 

[Kayvan]

See mid engine wipeouts on YouTube

Almost all are easing off power on crest of turn or crown

Audi r8 and Gt are some shown

 

[twobjshelbys]

Are you talking about going into a turn or straight?

If you are attempting, for example, a passing situation, and attempt to downshift just before accelerating the rear tires can break loose due to the sudden RPM change. You can help with a heel-toe throttle blip but even then the mismatch might be too much for the tires to hold. With the Cobra I knew absolutely what the trip points were but one day a friend was test driving. It was cool day. We stopped for a little while at his friend's place to look at one of his cars and chatted for about 1/2 hour. I took the wheel and was merging up to the highway speed (60MPH) and the rear broke loose for a very brief moment in the 2-3 shift. We were already close to 60 at the shift at about 5000RPM. I saved it before it could spin but it was close.

If you are going into a turn you are probably already braking and if you try to downshift it's much more likely to break loose, especially on cold pavement and cold tires. Since you are braking in the turn the weight transfer to the front has already started leaving the rear light, and the downshift RPM mismatch and torque transfer increases the probability that the rear tires lose grip and of a trailing throttle oversteer. Again with the Cobra there were some turns I could do extremely well and was confident in the handling of the car. One cool morning I took it at the same speed and shifted where I usually did and the rear broke loose on the 3-2 downshift. Fortunately it was early so there was no traffic and the curbs were far away.

The takeaway is that you get comfortable with the handling and response of the car and the temperatur, of all things, can be the down fall. I will observe that my Shelby GT came with a warning about driving in low temps too.

I haven't had the GT long enough to know its limits yet. I had seen all the experiences with the factory Goodyear F1 tires in the cold and switched to the Bridgestones to maybe help a little. They are quite a lot grippier than the Goodyears on the Cobra since I can leave the subdivision turn (again, from a standstill to a fair traffic clip) and do the turn without fear.

By the way, I will add that the FGT is absolutely the easiest car to do heel-toe I've ever driven. The brake and accelerator are very nearly planar. Just need to find a place to practice.

 

[TO AWSUM]

Steve,

I wouldn't worry about the FGT being any different than any other car, especially any other high horse power car. The physics are exactly the same. If you exceed the coefficient of friction, your tires will loose grip and you will spin the tires. It's that simple. Tires may seem to have less grip in a turn when you apply power but this is not true. The amount of friction the tires can withstand is the same. What has changed is part of the tire's friction is being used by the tires to maintain grip in the turn and is not available for accelleration (either for slowing or speeding up). If you drive too fast into a corner, you are going to go off the road. If you are too heavy footed especially when in a turn, you will go off the road or at the least spin out. All vehicles, vans, trucks, cars, etc. have their limits. If you exceed their limits, you will pay dearly for your mistake. That is all that is happening. As twobjshelbys said of the short wheelbased Cobra, it will snap into a spin in a heart beat, but under the exact same conditions, the FGT will not spin due to the FGT's wider stance, lower center of gravity, suspension improvements, wider tires, etc. If you want to hammer the gas pedal on a Cobra, you had better be pointing it in a straight line or you will be swapping ends in a fraction of a second. You never hammer a Cobra while in a turn, curve, or rock the steering wheel back and forth to break the tires loose like you see people do on the old '60s muscle cars. That is just flirting with disaster. Learn how to control your right foot and you will be OK.

 

[HHGT]

http://www.drivingfast.net/track/engine-driveline.htm#axzz1h6mxnOo2

 

[twobjshelbys]

Steve,

You never hammer a Cobra while in a turn, curve, or rock the steering wheel back and forth to break the tires loose like you see people do on the old '60s muscle cars. That is just flirting with disaster.

Absolutely correct on high power light cars. I see people rocking the steering wheel to demonstrate steering responsiveness and even do it myself. At low speeds it's a good test for loose steering system - try it some time on a real 65 Mustang compared to any modern car. But at high speeds it is almost a guarantee of something bad. Rocking the front whips the back.

The thing is I have yet to be able to cause the FGT do do anything bad. All that means is I haven't exceeded the limits but so far it has passed the tests I've given it. I'd like to get it to a skid pad.

 

[Mullet]

inexperience.

I can spin at 80mph on the freeway on R6's in 35 degree weather and keep it from spinning around.

 

[Black GT]

inexperience.

I can spin at 80mph on the freeway on R6's in 35 degree weather and keep it from spinning around.

Yea, I agree with you on that, but sometimes no matter how good you are you can loose it. Saying that, I was out on a day when it was 38 or 40 degrees. I was turning right coming out on a main road and got on it. Long story short, she got sideways on me and i corrected it, but someone inexperienced would have lost it. I have been driving high powered rear wheel drive cars for years. I miss the feeling of a rear wheel drive car and burning out and getting the ass end out when I drive my Lambos or Porsh for too long

 

[Luke Warmwater]

Seems like there are different ways to lose it. Being on the track at the edge of adhesion is one thing. Spinning your tires taking off and having it come around on you is another. Anyone ever find a big empty parking lot devoid of obstructions and do a little drifting? I think some people get in trouble when the rear end comes loose and they simply have not no idea how it should feel so they do something abrupt and lose it. I used to leave twin squiggly streaks entering on to the blvd when there was no traffic on a couple or three occasions. Never once felt it start to get away. If you're worried about it go practice so it won't surprise you when it happens. Cold pavement and tires made this even easier.

 

[BlackICE]

Seems like there are different ways to lose it. Being on the track at the edge of adhesion is one thing. Spinning your tires taking off and having it come around on you is another. Anyone ever find a big empty parking lot devoid of obstructions and do a little drifting? I think some people get in trouble when the rear end comes loose and they simply have not no idea how it should feel so they do something abrupt and lose it. I used to leave twin squiggly streaks entering on to the blvd when there was no traffic on a couple or three occasions. Never once felt it start to get away. If you're worried about it go practice so it won't surprise you when it happens. Cold pavement and tires made this even easier.

Good advice, but be careful in CA, you could get cited for display of speed just because your tires are squealing.

 

[TO AWSUM]

http://www.drivingfast.net/track/engine-driveline.htm#axzz1h6mxnOo2

Exactly what I was trying to explain. Going over a hill too fast or over a curb is going to take weight off the tires creating less friction between the road and tires. If power is added at the same time, guess what, you're going to spin out or go off the road. Pretty simple concept. Thanks.

 

[Luke Warmwater]

Like this

[video=youtube;gQLM-K9TwWM]http://www.youtube.com/watch?v=gQLM-K9TwWM[/video]

 

[KJRGT]

I would say it is more of a driver skill/experience problem than anything else, the car is very stable when you consider the power to weight. An experienced driver will evaluate the available grip with moderate throttle application and then determine how much throttle is appropriate for the available grip. Just mashing the throttle is an invitation for a loss of control especially in cold weather where the engine is making 50-75 more horse power and the tires have even less grip. A race car and I don't mean some track day special, is very unstable for about a lap or two and would spin out in a heart beat if the driver just wacked the throttle open, why would a GT driving down the street on cold tires be any different? The whole problem in a nut shell is how quickly and how far the throttle is opened, treat it with respect and you won't have a problem.

+++ 1 Cobra 498.

Steve, I doubt a "good experienced driver" would lose control on a GT to the degree it means going off road. Now that being said, even the best of professional racers make mistakes. I think as Cobra 498 states, some drivers just hammer the throttle without really knowing what the traction is like at the time. Always "test" traction first by applying partial throttle prior to putting down the hammer.

 

[jbyrnes]

It would be good to hear from some of the weekend warriors who've done alot of track time on the GT, but in my limited track experience with a mid engine car I've learned to get on the gas when the back end starts coming around in the corners. Counterintuitive and scary to be giving throttle as you start loosing control, but in a trailing throttle oversteer situation where the car has transferred weight off the rear tires past their traction limit, a little gas can get the weight and traction back on the loose tires if you're carefull and things straighten right out - presuming you haven't gone in too deep beyond what the fronts can handle too. I haven't been there yet in the GT but I presume it too follows the same laws of car control.

 

[FBA]

Unlike the Viper, which is a bitch to drive using the normal techniques...guess that's why they named it after a deadly snake. LOL