F-Type ( X152 ) 2014 - Onwards
Sponsored by:
Sponsored by:

Death Machine

Thread Tools
 
Search this Thread
 
  #1  
Old 10-03-2015, 05:27 PM
XFactoR's Avatar
Senior Member
Thread Starter
Join Date: Jun 2010
Location: New Jersey
Posts: 401
Received 70 Likes on 58 Posts
Default Death Machine

I have a 2015 RWD R coupe with 15,000 miles on it...always fun, a little wild but controllable....but, it almost killed me the other day and I'm freaked out because there is little rhyme or reason for the event....

I was driving on a blacktop highway at about 60 mph, in the rain and I wanted to show a friend how the exhaust baffles open up at higher RPMs even when the active exhaust is off...

I was going dead straight...shifted from 6th gear to 4th, and the car pitched into a viscous high speed spin next to a concrete divider...luckily with good skill and God, I carefully corrected the car from spinning and then pitching in the opposite direction after correction....it scared the $&@@ out of me because it never did that to me before.

I was in normal mode....not dynamic and I didn't hydroplane on water....

The funny thing is that the car felt loose the entire day but I don't know why... Could it be the tires? It appears that I have even tread all throughout....is there a point on the P zeros that they simply are not functional in the rain, even with tread?

I've gone to many high performance driving schools and the last time I did the R performance academy, it was in the pouring rain...no problems whatsoever.

I used to think AWD was kinda dumb on this car, I'm rethinking it totally....

Any input would be helpful.
 
  #2  
Old 10-03-2015, 05:41 PM
Unhingd's Avatar
Veteran Member
Join Date: Dec 2014
Location: Maryland, US
Posts: 16,939
Received 4,649 Likes on 3,362 Posts
Default

Originally Posted by XFactoR
I have a 2015 RWD R coupe with 15,000 miles on it...always fun, a little wild but controllable....but, it almost killed me the other day and I'm freaked out because there is little rhyme or reason for the event....

I was driving on a blacktop highway at about 60 mph, in the rain and I wanted to show a friend how the exhaust baffles open up at higher RPMs even when the active exhaust is off...

I was going dead straight...shifted from 6th gear to 4th, and the car pitched into a viscous high speed spin next to a concrete divider...luckily with good skill and God, I carefully corrected the car from spinning and then pitching in the opposite direction after correction....it scared the $&@@ out of me because it never did that to me before.

I was in normal mode....not dynamic and I didn't hydroplane on water....

The funny thing is that the car felt loose the entire day but I don't know why... Could it be the tires? It appears that I have even tread all throughout....is there a point on the P zeros that they simply are not functional in the rain, even with tread?

I've gone to many high performance driving schools and the last time I did the R performance academy, it was in the pouring rain...no problems whatsoever.

I used to think AWD was kinda dumb on this car, I'm rethinking it totally....

Any input would be helpful.
The P-Zeros on my MINI scare the $rap of me in the rain, and they just sit there and smoke from a stop on dry pavement. That's why I changed to he PSSs on the F before I even picked up the car. We've had some heavy rain the last few days and the wet traction is astounding me. Also can't get the tires to really light up on dry pavement. The clutch slips long before the tires will. The Pirellis might be better for drifting.
 
  #3  
Old 10-03-2015, 05:47 PM
TXJagR's Avatar
Veteran Member
Join Date: Feb 2015
Location: Dallas, TX
Posts: 4,323
Received 293 Likes on 233 Posts
Default

I'll offer... Rain, Wet, New Jersey in October probably = cold, 550 hp, RWD, and downshift 2 gears...


 
The following users liked this post:
buickfunnycar.com (10-04-2015)
  #4  
Old 10-03-2015, 05:57 PM
StealthPilot's Avatar
Senior Member
Join Date: May 2011
Location: South east
Posts: 910
Received 147 Likes on 115 Posts
Default

sorry never felt scared in the rain, the car is quite predictable and I drive the car in dynamic mode in the rain most of the time.

This sounds like the crappy pirelli tires, combined with misjudging the traction.
 
  #5  
Old 10-03-2015, 10:07 PM
XFactoR's Avatar
Senior Member
Thread Starter
Join Date: Jun 2010
Location: New Jersey
Posts: 401
Received 70 Likes on 58 Posts
Default

I obviously misjudged the traction...but I was shocked how bad it was and how out of control the car was....it never did that to me ....

I drove the car hard on the track at Monticello in the pouring rain in dynamic mode and had nothing close to that happening.....

it was really bizarre...

I will add that today my TPMS told me all 4 tires were low (temperature change) ...they were at 26 psi instead of 36. I filled them up and we'll see if that makes a difference.
 
  #6  
Old 10-03-2015, 10:20 PM
AnD3rew's Avatar
Senior Member
Join Date: Jan 2013
Location: Sydney Australia
Posts: 952
Received 172 Likes on 124 Posts
Default

I posted something similar, although not quite as dramatic a little while ago. Same thing wet road, I gave it only a moderate bit of throttle and mine is a V6S not a V8R but the back momentarily tried to overtake me.
 
  #7  
Old 10-03-2015, 10:21 PM
Foosh's Avatar
Veteran Member
Join Date: Jul 2014
Location: Maryland, USA
Posts: 6,177
Received 1,026 Likes on 854 Posts
Default

Originally Posted by TXJagR
I'll offer... Rain, Wet, New Jersey in October probably = cold, 550 hp, RWD, and downshift 2 gears...
Agreed, the explanation is simple. Don't do that again at highway speeds when it's wet and cool, and it was in the mid-50's today. You're on summer performance tires. Today's temps in the mid-Atlantic aren't summer, plus you instantly upset the car with the 2-gear downshift. Moreover, at 60mph, you were likely in a mild hydroplane situation so you didn't have full traction when you jacked up the rpms, which produced an instant spin.

I don't care whether they were PSS or PZeros, the result would have been the same. What you did was worse than burying the throttle under the same conditions, because you created a sudden braking situation with the downshift, while breaking the rear tires loose.

The car is not the "death machine" in this case.
 

Last edited by Foosh; 10-03-2015 at 10:45 PM.
The following 3 users liked this post by Foosh:
99Gsp (10-04-2015), FrickenJag (10-05-2015), TXJagR (10-03-2015)
  #8  
Old 10-03-2015, 10:46 PM
XFactoR's Avatar
Senior Member
Thread Starter
Join Date: Jun 2010
Location: New Jersey
Posts: 401
Received 70 Likes on 58 Posts
Default

I hear ya...but I was tearing that car up at Monticello in the rain and it was glued....
 
  #9  
Old 10-03-2015, 11:44 PM
Nookieman's Avatar
Senior Member
Join Date: Mar 2015
Location: Enumclaw, Washington U.S.A.
Posts: 678
Likes: 0
Received 104 Likes on 79 Posts
Default

Originally Posted by XFactoR
I hear ya...but I was tearing that car up at Monticello in the rain and it was glued....
How many miles were on the tires and how warm was it at the track day? 15,000 miles is a lot on the Pirellis, especially if accumulated over lots of short trips. They tend to degrade with heat cycles so even if they have tread left they do not offer a lot of grip when well-used. A new set will bring back the performance you remember, at least when warm.
 
  #10  
Old 10-04-2015, 06:23 AM
mshedden's Avatar
Senior Member
Join Date: Aug 2014
Location: Central Virginia
Posts: 701
Received 192 Likes on 128 Posts
Default

I'd suggest (at least for now) changing out the tires for some performance all seasons that are more suited to the temps/conditions you're likely to encounter at least in the next 6 months in NJ. Given your mileage of 15K it sounds like you're driving the car a fair amount, and unlikely to park it over the winter.

Summer tires (esp worn out ones) just aren't going to cut it, esp on the R.

I don't know what the current 'best' all season tire is - maybe a Michelin or a Continental Extreme Contact DWS?
 
  #11  
Old 10-04-2015, 06:44 AM
1 of 19's Avatar
Veteran Member
Join Date: Oct 2014
Location: Eau Claire, WI.
Posts: 1,749
Received 734 Likes on 470 Posts
Default

My P-Zeros are useless when it gets 50 degrees or cooler. Cannot be trusted. Ever. When its 70 degrees out... they rock.
 
  #12  
Old 10-04-2015, 09:08 AM
XFactoR's Avatar
Senior Member
Thread Starter
Join Date: Jun 2010
Location: New Jersey
Posts: 401
Received 70 Likes on 58 Posts
Default

I drove it last winter when the car and tires were new...it wasn't anywhere as unstable...I'm perplexed about how bad the traction has degraded even with decent tread left.....
 
  #13  
Old 10-04-2015, 09:19 AM
Join Date: Oct 2009
Location: Perth Ontario Canada
Posts: 11,058
Received 2,255 Likes on 1,840 Posts
Default

Originally Posted by Foosh

The car is not the "death machine" in this case.
Glad somebody said it. There's too much faith being put in computerized traction and stability systems.
 
  #14  
Old 10-04-2015, 09:19 AM
RickyJay52's Avatar
Veteran Member
Join Date: Oct 2014
Location: Northeast
Posts: 3,392
Received 1,593 Likes on 857 Posts
Default

Originally Posted by mshedden
I don't know what the current 'best' all season tire is - maybe a Michelin or a Continental Extreme Contact DWS?
I researched the best rated Ultra-High Performance All-Season tire on TireRack.com and the overwhelming favorite - at #1, with far and away the most miles logged - was the Continental Extreme Contact DWS which I've purchased for driving this winter, in Maine. While quite a differ car, I also have them on my Audi A8L and they're superb! I'm quite curious to see how well they'll perform on my F-Type and looking forward to pushing the limits a bit more this winter (while I sit here on Isla Mujeres, Mexico with the Caribbean Ocean as my back-drop). In other words, winter tires - any tires - are the last thing on my mind.
 

Last edited by RickyJay52; 10-04-2015 at 09:26 AM.
  #15  
Old 10-04-2015, 09:57 AM
XFactoR's Avatar
Senior Member
Thread Starter
Join Date: Jun 2010
Location: New Jersey
Posts: 401
Received 70 Likes on 58 Posts
Default

Everybody's responses have been great, but I do think the question remains... Do you really think a car should almost spin out at highway speeds in the rain during 50 degree weather just for being downshifted 2 gears on an 8 speed gearbox (closer ratios)????

My XFR didn't ever threaten my safety like that even when I would drive it like an idiot in bad weather with summer tires.....

Either there is something dynamically amiss with the F-Type or the P zeros suck that bad....(I think it may be a combo of both)
 
  #16  
Old 10-04-2015, 10:04 AM
Join Date: Oct 2009
Location: Perth Ontario Canada
Posts: 11,058
Received 2,255 Likes on 1,840 Posts
Default

Originally Posted by XFactoR

My XFR didn't ever threaten my safety like that even when I would drive it like an idiot in bad weather with summer tires.....
Why would you put that much faith in computers making up for an unreasonable/unsafe driving style?

Obviously your action of downshifting caused enough drag on the tires that they broke traction. Doing so on wet pavement was just asking for trouble.
 
  #17  
Old 10-04-2015, 10:43 AM
Foosh's Avatar
Veteran Member
Join Date: Jul 2014
Location: Maryland, USA
Posts: 6,177
Received 1,026 Likes on 854 Posts
Default

Originally Posted by XFactoR
Everybody's responses have been great, but I do think the question remains... Do you really think a car should almost spin out at highway speeds in the rain during 50 degree weather just for being downshifted 2 gears on an 8 speed gearbox (closer ratios)????

My XFR didn't ever threaten my safety like that even when I would drive it like an idiot in bad weather with summer tires.....

Either there is something dynamically amiss with the F-Type or the P zeros suck that bad....(I think it may be a combo of both)
I don't think any question remains, and it's a driver, not car error. It's simple physics. Consider the two scenarios below:

1) In the rain, at highway speeds, a driver suddenly executes a 2-gear down-shift which introduces a braking action that instantly shifts the weight balance of the car forward. The rear wheels are spun up because of the sudden rpm increase, so the tires lose all traction and are spinning on the wet pavement, introducing a sideways movement, with a now suddenly unloaded rear-end. The law of conservation of momentum predicts that the now unloaded, traction-less rear-end is going to keep going forward, which it does with spinning rear wheels pushing it sideways, but the front-end is more planted = spin.

2) In the rain, at highway speeds the driver suddenly buries the throttle which does not introduce the braking force and instantly shifts the weight balance of the car rearward or keeps it more neutral. Rear tires lose traction on wet pavement, and car may wiggle a bit, but maintains forward motion without spinning.

Professional drivers continually reinforce the importance of keeping a car as balanced as possible under all conditions and avoid abrupt weight transfers, or in other words, "don't upset the car." All weight transitions should be very smooth (e.g. not sudden). Cool tires on wet pavement make those principles even more important because loss of control can happen much quicker and exceed the stability control system's capability to correct for it before loss of control.
 

Last edited by Foosh; 10-04-2015 at 12:34 PM.
The following 5 users liked this post by Foosh:
FrickenJag (10-05-2015), MarcusXFR (10-05-2015), Mikey (10-04-2015), TR64ever (10-05-2015), TXJagR (10-04-2015)
  #18  
Old 10-04-2015, 12:38 PM
StealthPilot's Avatar
Senior Member
Join Date: May 2011
Location: South east
Posts: 910
Received 147 Likes on 115 Posts
Default

Originally Posted by XFactoR
Everybody's responses have been great, but I do think the question remains... Do you really think a car should almost spin out at highway speeds in the rain during 50 degree weather just for being downshifted 2 gears on an 8 speed gearbox (closer ratios)????

My XFR didn't ever threaten my safety like that even when I would drive it like an idiot in bad weather with summer tires.....

Either there is something dynamically amiss with the F-Type or the P zeros suck that bad....(I think it may be a combo of both)
I am sure you didn't just downshift. You must have changed throttle application too. Nobody just downshifts without intent to use throttle.

Have you been to a professional driving school like the BMW 2 Day M School?

If not I would highly recommend it. I learned a lot about driving in the wet.
 
  #19  
Old 10-04-2015, 12:44 PM
Foosh's Avatar
Veteran Member
Join Date: Jul 2014
Location: Maryland, USA
Posts: 6,177
Received 1,026 Likes on 854 Posts
Default

Originally Posted by StealthPilot
I am sure you didn't just downshift. You must have changed throttle application too. Nobody just downshifts without intent to use throttle.
Perhaps, but timing is everything.

If the downshift was initiated just prior to the intended application of throttle, the snap spin was likely initiated before he made it to the throttle. Since everything happened so quickly, it would be impossible to accurately reconstruct one's actions through the adrenalin fog.
 
  #20  
Old 10-04-2015, 02:28 PM
StealthPilot's Avatar
Senior Member
Join Date: May 2011
Location: South east
Posts: 910
Received 147 Likes on 115 Posts
Default

To the OPs point, I do think the shifts in the R Coupe are nowhere near as smooth as the BMW DCT in my M5. I do think shift smoothness can contribute to this sort of thing.
 


Quick Reply: Death Machine



All times are GMT -5. The time now is 07:27 AM.