Strange 997S Handling Characteristics...
#16
Originally Posted by eilig
Thanks for the insight guys. This gives me lots of stuff to practice during my upcoming drives. One more question:
Let's say I'm in a curve with lots of speed, and I'm feathering the throttle, and I start getting major understeer. So I get off the throttle, and start applying pressure to the brakes to try and get the front end to "bite" and get rid of that understeer. Do I have to worry about the back end coming around on me when I apply the brakes?
Whenever I have the thought of getting on the brakes mid-turn, especially when I'm carry quite a bit of speed through there, I have flashbacks to a time when I did exactly the same thing driving a Viper GTS (piece of junk!) mid-turn. I got on the brakes, and that back end kicked out so fast that I almost lost it and spun. I did manage to get it straight again, but not without some serious wrestling, and going off-road into the desert (I was driving a rental out near Vegas at the time).
So, let's say I'm mid-corner, and as a worst case scenario, say I missed the apex and I'm getting big time understeer. Do I have to worry about the rear of the 997S kicking out suddenly if I get on the brakes?
Thanks for allowing me the benefit of learning from your experience!!
Let's say I'm in a curve with lots of speed, and I'm feathering the throttle, and I start getting major understeer. So I get off the throttle, and start applying pressure to the brakes to try and get the front end to "bite" and get rid of that understeer. Do I have to worry about the back end coming around on me when I apply the brakes?
Whenever I have the thought of getting on the brakes mid-turn, especially when I'm carry quite a bit of speed through there, I have flashbacks to a time when I did exactly the same thing driving a Viper GTS (piece of junk!) mid-turn. I got on the brakes, and that back end kicked out so fast that I almost lost it and spun. I did manage to get it straight again, but not without some serious wrestling, and going off-road into the desert (I was driving a rental out near Vegas at the time).
So, let's say I'm mid-corner, and as a worst case scenario, say I missed the apex and I'm getting big time understeer. Do I have to worry about the rear of the 997S kicking out suddenly if I get on the brakes?
Thanks for allowing me the benefit of learning from your experience!!
From the factory, as some one else has said, there is a lot of understeer built into the car. In addition, there's the PSM to help out (although even that's flawed in certain situations). In all likelihood, you would have to be travelling at an insane speed, have very jerky inputs, to get it out of shape. These cars like to be driven with a certain accuracy, and will reward you for it. Can't chuck it into a turn, correct, turn, correct, etc., and be fast all at the same time.
Go for more trackdays and find out some more!
#17
Originally Posted by Likemystoppie?
I had a very similar experience with the 997 carrera I tested 2 weeks ago.
So my NEXT question is.....Are these cars that DAMN sensitive to tire pressure?
edit: and how come you guys didn't tell me the same informative dialog you've shared with this person?
So my NEXT question is.....Are these cars that DAMN sensitive to tire pressure?
edit: and how come you guys didn't tell me the same informative dialog you've shared with this person?
Actually, it's not the car that's affected (not directly, at least) by tire pressures. It's the tire itself that determines how the car handles. If the tire isn't inflated enough, you'll roll right off the tire and onto the wheel. If the tire is over-inflated, the tire's tread can't roll with the road surface. Ask the track gurus, for more specific information about this. Another example: On trackdays, I start with a cold reading of 30 psi, but after about 4 laps, the psi jumps up to 48. Then the tail usually starts to squirm a bit at this point, so I let out the psi down to 30-32 (hot) and I find more grip.
#18
Originally Posted by eilig
Thanks for the insight guys. This gives me lots of stuff to practice during my upcoming drives. One more question:
Let's say I'm in a curve with lots of speed, and I'm feathering the throttle, and I start getting major understeer. So I get off the throttle, and start applying pressure to the brakes to try and get the front end to "bite" and get rid of that understeer. Do I have to worry about the back end coming around on me when I apply the brakes?
Whenever I have the thought of getting on the brakes mid-turn, especially when I'm carry quite a bit of speed through there, I have flashbacks to a time when I did exactly the same thing driving a Viper GTS (piece of junk!) mid-turn. I got on the brakes, and that back end kicked out so fast that I almost lost it and spun. I did manage to get it straight again, but not without some serious wrestling, and going off-road into the desert (I was driving a rental out near Vegas at the time).
So, let's say I'm mid-corner, and as a worst case scenario, say I missed the apex and I'm getting big time understeer. Do I have to worry about the rear of the 997S kicking out suddenly if I get on the brakes?
Thanks for allowing me the benefit of learning from your experience!!
Let's say I'm in a curve with lots of speed, and I'm feathering the throttle, and I start getting major understeer. So I get off the throttle, and start applying pressure to the brakes to try and get the front end to "bite" and get rid of that understeer. Do I have to worry about the back end coming around on me when I apply the brakes?
Whenever I have the thought of getting on the brakes mid-turn, especially when I'm carry quite a bit of speed through there, I have flashbacks to a time when I did exactly the same thing driving a Viper GTS (piece of junk!) mid-turn. I got on the brakes, and that back end kicked out so fast that I almost lost it and spun. I did manage to get it straight again, but not without some serious wrestling, and going off-road into the desert (I was driving a rental out near Vegas at the time).
So, let's say I'm mid-corner, and as a worst case scenario, say I missed the apex and I'm getting big time understeer. Do I have to worry about the rear of the 997S kicking out suddenly if I get on the brakes?
Thanks for allowing me the benefit of learning from your experience!!
b.) You really need to get some instruction and learn about the basics of vehicle dynamics in a controled environment.
The Chicago PCA chapter is a great and active group.
PDE is great as well.
It sounds as if you have driven some cars however it also sounds like you really don't know how to drive either. Smooth is one of the keys as in the previous post, and another is vision
Getting the car out on the track (read controled environment) will most likley temper your youthfull exuberance to driving fast on public roads.
The track experience lets you really experience the capabilities of your car, that is near to impossible to do on a public road.
It's such a rush to have the car wiggle!
Drive within your limits and have fun.
If it feels exciting...slow down
#19
Excuse me for butting in but don't these cars have stability management which allows INDIVIDUAL wheels to be braked (which, of course cannot be replicated manually)? I.e., understeer will cause breaking of the inside rear wheel and oversteer the outside front wheel and/or reduce the throttle.
#20
I'm glad this ended happily because the day before this thread started I heard a story that popped into my head immediately upon reading about the strange handling. The story: A guy returns to the dealer claiming that his brand new Porsche has a very bumpy ride and handles very strangely. Upon inspection, they found that the transport clamps around the springs (placed so the car doesn't bounce around during shipping) were still attached. Made me wonder what else they forgot to do.
#21
Jim -- Actually, in looking at the service records that came with the car, I noticed it had been in the shop back in January for: "Tighten rear sway bar link." Hopefully this has nothing to do with what I experienced. Then again, maybe I'll crawl underneath and make sure everything seems secure!
#22
eilig, good that your enjoying your new 997
all cars (especially street cars) understeer when entering a corner at higher speed than the car can handle. once speed drops and the front tires bite the car turns in. this has nothing to do with weight distribution of the 997.
when the speed drops and the front tires bite the 997 would turn in quicker than a vette because its lighter font end.
the suggestion from the guys to trail brake into the corner is good one. rear engine cars are much happier with trail braking because you keep more weight on the front tires during turn in and that reduces understeer and lets you enter the corner at a higher speed compared to no trail braking.
to correct for understeer inside a turn your inputs should be very smooth. you can reduces throttle, gently tap the brakes (you can do that with your left foot but it requires practice to develop left foot sensitivity) , or be a hero on the track and induce controlled oversteer and powerslide through the turn
my 2cents.
all cars (especially street cars) understeer when entering a corner at higher speed than the car can handle. once speed drops and the front tires bite the car turns in. this has nothing to do with weight distribution of the 997.
when the speed drops and the front tires bite the 997 would turn in quicker than a vette because its lighter font end.
the suggestion from the guys to trail brake into the corner is good one. rear engine cars are much happier with trail braking because you keep more weight on the front tires during turn in and that reduces understeer and lets you enter the corner at a higher speed compared to no trail braking.
to correct for understeer inside a turn your inputs should be very smooth. you can reduces throttle, gently tap the brakes (you can do that with your left foot but it requires practice to develop left foot sensitivity) , or be a hero on the track and induce controlled oversteer and powerslide through the turn
my 2cents.
#23
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if you don't like that initial understeer, get more aggressive alignment.
perhaps slow down way more when entering a turn, wait until front end hooks up, then gradually goto wot at or slight before apex. way slow in, fast out.
of cousre don't do this on public street, try it on track.
perhaps slow down way more when entering a turn, wait until front end hooks up, then gradually goto wot at or slight before apex. way slow in, fast out.
of cousre don't do this on public street, try it on track.
#24
Eilig-
Good thing you live in Illinois where it is pretty flat, but your understeer could put you in a ditch.
Remember It's not the car, it's the driver.
WATCH THIS!
Good thing you live in Illinois where it is pretty flat, but your understeer could put you in a ditch.
Remember It's not the car, it's the driver.
WATCH THIS!
#25
Originally Posted by boolala
Excuse me for butting in but don't these cars have stability management which allows INDIVIDUAL wheels to be braked (which, of course cannot be replicated manually)? I.e., understeer will cause breaking of the inside rear wheel and oversteer the outside front wheel and/or reduce the throttle.
#27
PDE is located just outside of Birmingham, Alabama in Leeds, AL. It's their only location.
http://www.porschedriving.com
Nice set of pics & video from the Aug 9-10 Masters here:
http://imageevent.com/walks357/pdeaug2005
http://www.porschedriving.com
Nice set of pics & video from the Aug 9-10 Masters here:
http://imageevent.com/walks357/pdeaug2005
#30
Originally Posted by OCBen
Thanks. Are the Skip Barber schools altogether different and unaffiliated then?
George Barber spent somewhere around 60-70 million $$ to house his MC collection and have a track to test them on. The Museum is a "living museum" where within a couple of hours almost any item in the collection can be up and running.
Interesting info here:
http://www.barbermuseum.org/