[Seven30]

So I have been bitten twice by my 968 in the wet.



First time was a spin into the gravel trap at a measely 0.835G running semi slicks. Left hand corner at 45MPH. Rear end came around without warning, I didn't stand a chance. This happened mid-corner, and before I would normally try to accelerate out of that corner, so spinning rear tires was not the issue.



Second time around, a faster car came up from behind on a track day, and I let him by on the top of a hill in a right hand corner at 40MPH. Problem was that I let go of the throttle and turned the steering wheel a bit more to let him pass. Result was a spin into the armco. Tires were Ultra High Performance. I wasn't fast enough to catch it.



The dynamics are pretty clear; first time the speed was too high, second time the lift-off plus steering input combined with a hilltop slowed down the rear enough -while removing weight from the tires- to loose grip.



I've noticed that going down the very steep 200-yard hill by my house, the 968 -if left in first gear- will come to a stop downhill. The other cars I'm driving will need a good push on the brake pedal 3-4 times not to break the speed limit.



Same thing where I work; a small downhill where the 968 will lock up its rears if there is a bit of gravel there.



I presume this is due to the high compression in the 3-liter inline-four?



Anyone else think the 968 swaps ends very fast in the wet?



On a dry track, catching the rear is usually not a problem, I just can't pick up the signal from the rears in time to make a correction before the s*** hits the fan.



Reading about a turbo 968 (Aussie) and a 944 (British) in a couple of magazines, the journos report that the 968/944 turbos try to kill them in the wet.



Just trying to understand why, so I'll be better prepared next time around.



Any input/thoughts are appreciated <img src="/forum/images/smilies/968/smile.gif" class="smilie" alt="" />

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[craigawoodman]

Not sure why this is the case with your car. Have you had the car corner weighted to see if it is balanced properly and had the shocks checked. If you are running coil-overs it is possible to get the car to an almost perfect 50/50 split.



Other potential issues could be the tyres, either pressures or just the tyres themselves. If the tyres are old, then they will have limited grip, but at 40mph this should not be a problem. If the tyres are cold, there will be limited grip and warning of impending break-away. THe type of tyre will also have a bearing on the amount of progression you have prior to the limit being exceeded. My old Pirelli's are not as progressive at the limit as the Dunlops I now run when hot, when cold it is reversed.



I track my car extensively and at around these speeds it is fool proof. At much higher speeds, I can pull around 1.3G in corners.



Other issues could be a broken sway bar, broken torsion spring on one side, etc. Is the problem only in one direction (i.e. turning one way?).



How does the car behave out on the road on normal tyres?



THe 968 was regarded as the best handling car in the world in it's day. It will run rings around a 911 as it can brake in something other than a straight line unlike a 911.



If the car is trying to spit you off the track like this there has to be an issue. Even running Dunlop Dizerra D03's in the wet, I do not have this problem - they have as much grip in the wet as a normal road tyre (assuming they have some tread remaining).

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[rl968]

I track my 968 and I've spun with it twice. The first time was going around a hairpin turn in the Octopus at Thunderbolt, just went too fast and missed the turn, back end came around on me. The second time was in Watkins Glen, going up hill around a turn in the rain. Had all four tires on slippery concrete, gave it a little gas and it immediately went into a nasty spin. Both times, the car was completely out of control and I could not recover it (had to wait until car came to a stop.) I run Sport Cups.



This might draw a few arguments (maybe an interesting discussion), but I feel that my 86 911, which I no longer track, handles better and is more predictable than the 968, but the 968 has a lot more power and is equally fun to drive. Agree that braking is better in the 968. With the 911, if you feel the back end moving, you give it gas and it straightens out. With the 968, it's less clear to me that is the proper strategy. I've only been tracking for 2 years so it may partly be that I don't have enough seat time yet.

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[craigawoodman]

From memory, there was a series of articles in one of the UK Porsche magazines on how to drive a Porsche. This was written for both the 911 and all of the other Porsches (Boxster - mid engine, 944/968/928 - transaxle & front engine). THese were good articles on the balance of the cars and the differences in driving techniques.



As per above, a 911 will increase grip as weight is transferred to the rear tyres (and is why you do not brake or lift off when cornering in a 911). We had a 911 swap ends after the flag at LAkeside and spin off into the wall at high speed - he simply lifted off going through a kink left.



At the limit, the 968 should be progressive. Rain will decrease this somewhat. General rule for rain is progressive application of all controls, brakes, steering and throttle - smooth is the key. I have looped my 968, but it has normally been that I have been too hot into the corner and pushing just a little too hard, but it has been telegraphed and a reasonable response.



The only time I have spun the 968 when it was totally unexpected was at Eastern Creek, on the out/warm-up lap - not even at race pace (I have a video out of the car somewhere). Out of the pits, down to turn 2 (which is normally a 2nd gear corner), took the corner in 3rd gear slowly and coming out applying a little throttle, the car looped. And this was dry. Not sure if I was on the paint or why it happenned - but this is the exception to the rule. Once again, the tyres were not up to temp and pressure as well.



Perhaps being in a lower gear puts you out of the peak torque area, or normally the car is more heavily loaded through this section and hence has more grip.

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[flash]

i am wondering if it has a clutch type lsd - that could do that off throttle in a turn (whereas an open diff could do it on throttle) - a torsen would be more progressive

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[pure&amp;simple]

I've spent a good amount of time on a skid pad, and not had any issues initiating or controlling a drift on wet pavement. One thing I have noticed - 968s seem to be particularly sensitive to camber changes in the road. I almost spun on the street once when I made a left-hand turn from a stoplight onto a steeply crowned road. As I crested the crown in the center of the road and the rear wheels hit the off-camber part of the road, the rear almost came around (no LSD at that point). It surprised me as I didn't think I was driving aggressively at all. I've only spun once at the track, and it was in the wet at Watkins Glen coming onto the main straight. I had 2 wheels on concrete and two on asphalt. When I came back on to all 4 wheels on asphalt I had the car almost completely straight and was just starting to give it some gas, but the rears broke loose and I spun 180 degrees with absolutely no chance to catch it. Had a clutch LSD at that point. Kinda scary trying to refire the engine watching cars coming towards me.

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[flash]

this is exactly why i continually harp on people who put too much negative camber in the setup - extreme camber results in less net contact patch area, which results in spin in the wrong conditions - the key is to increase the sum of the contact patch areas of all of the tires, and not just the outside tires - i see this all the time with guys who put something silly in there like -3 degrees - that's just too much - better to get the chassis set up right, and get the springs and anti-roll bars right than to dump a lot of negative camber in there and spin out with the least provocation - before i go adding negative camber, i try to move the weight of the car back to the inside by means of chassis bracing to reduce suspension flex and camber change, springs to reduce the weight transfer, and anti-roll bars to further control the body roll, which inherently affects contact patch area



this may or may not be the problem in this case, and i'd still like to know what diff is in there, but it is also something to look at



the bottom line is that something got upset when the weight transfer occurred - that needs to get sorted out

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[Seven30]

Gents,



Thank you very much for your responses <img src="/forum/images/smilies/968/smile.gif" class="smilie" alt="" />



When I spun mid-corner, I was running Michelin Pilot Sport Cups. There was no diff, the dampers were Koni, sways were M030. Strut brace KLA. Standard 968 camber/caster/toe. This was on lap 10(-ish), chasing down a 964RS.



When I spun after the hill-top with too much steering input and throttle lift-off, I was running Goodyear Eagle F1 Assymetrics. The diff is GT with 80/80 ramps. Torsion bars gone, coil-overs KW Competition 3-way, same sways. Strut brace D1, all suspension rubber replaced with metal or delrin. Moderate camber/caster/toe by race shop intimately familiar with the track and KW. This was on lap 11, and I was going slow all day -shifting up at 5000RPM- because I don't feel safe in the wet...



I can accept that the driver (me) needs more experience in the wet, but things happens so fast I just don't pick up the signals in the wet. Even looking back I can't remember any sensation that I missed.



In the dry -or on the street- things are great. I'v been asked so many times what's under the hood by drivers of GT2s, GT3s, 996+997 Turbos, you name it, after a track day. That's a big part of the fun with the 240-horse 968 <img src="/forum/images/smilies/968/smile.gif" class="smilie" alt="" />

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[pmason]

Well I can't comment too much on my 968 as I've only picked up a few months ago but it drives so much easier than my 84 911 which I've been tracking for a couple of year, looped a number of times, one I have on video going sideways through the kink at RA just 2 ft off the wall. The 968 I have only broken it loose once and what I liked was the whole car slid sideways, just lightly feather off the gas and keep going.

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[Jim Child]

I see two possibilities for the first spin. Its very easy to hydroplane on MPSC's, especially with most of the tread worn away. Even with the car in steady state, mid corner you could have built enough water up under the outside rear tire for it to let go. A puddle or water flowing accross the track could have caused it, but with a semi slick tire on a wet track you don't even need that.



Another possibility is a surface chage in the middle of the corner. Are there any patches or sealer in that part of the track? In the wet minor surface changes that you don't even notice in the dry are enough to cause a loss of grip.



Sorry to say, but the second spin just sounds like driver error. Smoothness is everything in the wet. Any abrupt inputs in either throttle or steering will send you right off of the track. Practice, practice, practice...



That said you can make the car more benign in wet conditions. Softening the shocks all around will make the car more forgiving of non-smooth inputs. You can also disconnect the rear sway bar which will make the car less prone to oversteering off of the track.

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[flash]

well, i'd like to see what the setting were, and what the spring rates are, because you don't set this car up like really any other - frequently we see people over spring the car, especially in the rear - the things you do to other cars don't work right on this one, but i'm also not saying that the setup is wrong either, since i don't know what it is



you aren't far from me - i could take a look



by the way, what track were you at?

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[Seven30]

Wish I could tell you the settings, but this was the first shot at finding the correct set-up, and it sort of ended before they could make a new adjustment...



The car was corner balanced, and ride height, caster, camber, toe was adjusted. I was planning to get a print-out when testing was done and the settings were as good as they could get them that weekend, but after the spin I didn't need to worry about settings for a while as the wheel base was shortened on one side...



The springs are just below 800# in the front and just below 900# in the rear. No torsion bars of course. Those are the spring rates, not the wheel rates.



Flash - you asked about the differential: Could the diff be contributing to the spins as well?



Have a nice weekend <img src="/forum/images/smilies/968/smile.gif" class="smilie" alt="" />

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[flash]

that's pretty stiff - it wouldn't be hard to have that spin in the wrong situation, but dependent a lot of how it is set up - most people do it wrong, because they try to set it up like other cars



if the diff is hitting its lockup point at the wrong time, it would upset the balance of the car, which is what generates spin



what track were you at?

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[Rap]

I am a new 968 driver and inexperienced. I was driving to work and going up giants despair in laurel run pa and had a come to jesus experience. I gave a slight punch on the second turn,I drive this road everyday several times a day, and was going sideways before I knew it. I was able to keep the car on the road, missed the guardrail. Apart from the fact that I am new and there might have been temp issues and shake on the road, drivers Ed school sounds in order. Anyone know when where in 2011?

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[rl968]

Yes. You can run with Schattenbaum, they have great DE's. They run in Millville NJ, at NJ Motorsports Park, two nearly brand new tracks, Thunderbolt and Lightning. They usually hold 2-day events. The next event will be in March. If that's too far for you, look for events at Pocono with another PCA club. You might also consider doing autoX, as that too will teach you how to handle a car that wants to break away from you.



You can get all of the info on the web page, the 2011 schedule isn't out yet, but there's info on what it's all about.



Here's the link: http://www.schattenbaum.org/DriverEd.aspx



Let me know if you have any questions; I'm a board member for SCH.

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[pure&amp;simple]

Schattenbaum is a great group! I've run with them a few times. If their events don't work out for your schedule, there are several other PCA chapters in the area and they all run at NJMP.

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