Tires
01-26-2003, 01:21 AM
#16
Nordschleife Master
Matt,
Sorry for the abbreviation. Substitute "handles well with aggressive driving" for my "works well". I am an experienced track driver, and I like this particular combo. I drove another TT today that had S02s all around, and it also "worked well". But it also had a lot more suspension work done to it than mine.
Sorry for the abbreviation. Substitute "handles well with aggressive driving" for my "works well". I am an experienced track driver, and I like this particular combo. I drove another TT today that had S02s all around, and it also "worked well". But it also had a lot more suspension work done to it than mine.
01-26-2003, 02:21 AM
#17
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Steve
I've had no experience w/either Bridgestone, but board posts from knowledgable drivers report very different performance characteristics for the S02 & S03. I don't understand how that disparity from mixed tires could do anything other than diminish your car's street handling, especially at/near the limit of either tire model.
I'll join the engineers from Porsche & stick with the mixed tires as a NO-NO rule.
I've had no experience w/either Bridgestone, but board posts from knowledgable drivers report very different performance characteristics for the S02 & S03. I don't understand how that disparity from mixed tires could do anything other than diminish your car's street handling, especially at/near the limit of either tire model.
I'll join the engineers from Porsche & stick with the mixed tires as a NO-NO rule.
01-26-2003, 02:48 AM
#18
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Well what a response! Even though I don't drive my car anywhere near the limits, I'm just going to put some SO2s in the rear. They handle like crap in the snow, but hey winter is almost over right?
01-26-2003, 03:08 AM
#19
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Sachin,
I use S-02' / S-03's (or R-compound Pirelli P-Zero C's) for warmer weather, but would urge you to consider a dedicated snow tire (e.g. Pirelli Wintersport 240) for winter driving in our part of the country. I've done a couple of nasty 360's on the street at only 5-15 mph on S-02's in the snow.
I use S-02' / S-03's (or R-compound Pirelli P-Zero C's) for warmer weather, but would urge you to consider a dedicated snow tire (e.g. Pirelli Wintersport 240) for winter driving in our part of the country. I've done a couple of nasty 360's on the street at only 5-15 mph on S-02's in the snow.
01-26-2003, 04:48 AM
#20
Burning Brakes
About different tread front/rear.
Pirelli recommends different tires:
Pzero Rosso Assimmetrico back
PZero Direzionale front
(Very different treads).
Or You can put all 4 asimmetricos if you like.
The PZero Rosso Direzionale is designed to offer enhanced hydroplaning resistance and is primarily for use on the lighter load carrying front axle positions of mid-engined and rear-engined rear-wheel-drive cars (which are combined with The PZero Rosso Asimmetrico tires on the rear axle positions).
<a href="http://www.tirerack.com/tires/tires.jsp?tireMake=Pirelli&tireModel=PZero+Rosso+Asimmetrico" target="_blank">Pirelli PZero</a>
Chris: I totally agree regarding tire pressure differences and think that it's essential.
Pirelli recommends different tires:
Pzero Rosso Assimmetrico back
PZero Direzionale front
(Very different treads).
Or You can put all 4 asimmetricos if you like.
The PZero Rosso Direzionale is designed to offer enhanced hydroplaning resistance and is primarily for use on the lighter load carrying front axle positions of mid-engined and rear-engined rear-wheel-drive cars (which are combined with The PZero Rosso Asimmetrico tires on the rear axle positions).
<a href="http://www.tirerack.com/tires/tires.jsp?tireMake=Pirelli&tireModel=PZero+Rosso+Asimmetrico" target="_blank">Pirelli PZero</a>
Chris: I totally agree regarding tire pressure differences and think that it's essential.
01-26-2003, 07:58 AM
#21
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Wow! What a thread. Having digested all the submissions I will wade in on this one. No one has had a "pop" at me on the board for a while so here will probably be an opportunity! 
Some strong opinions here, and that is good everything has some sort of value if you think it through.
There seem to be two distinct issues here:-
1) The balance between front and rear wear rates.
2) The mixing of tyres front versus rear.
With regard to 1. No weight has been given to the fact that Jack runs a supercharged car putting significantly more horsepower through his rears. Also from what I can see Jack's car is used primarily if not excusively on the road.
I would agree that on a track I would expect the front/rear wear rates to be closer, to achieve this on the road would lead me to ask, even as someone who would class themselves as a fast road driver " Which is going to wear out the faster your tyres or your driving license!" I also doubt that Jack really meant that his fronts were near perfect but more that they were still perfectly usable and didn't require changing.
In a track environment the wear rates will still be affected by the set up of the car and particularly the balance between over/understeer.
I have significant track time myself primarily on bikes, but also in cars, my personal preference is of course to a set up favouring oversteer which will result in slightly higher rear rather than front wear rates.
Forget the track for a moment and return to a road environment and take an extreme example.
Modern Superbikes put real world rear wheel BHP figures of between 130/150 through a contact patch the size of a cigarette pack, braking is taken care of via a front wheel twin disc system with 6 piston calipers and pretty much race spec pads along with a basically redundant rear brake (the wheel isn't touching the floor in anything above 7/10ths braking). Front tyres carry extreme loads on turn in and under braking. Again you have a tiny contact patch and consequently compounds are way softer than car compounds.
I personally have worn out rear tyres on the road in less than 800 miles. I have never changed a front in less than 3000. Why? I would suggest that in a road environment big BHP through the rear has more opportunity to be used than huge cornering or braking forces and outweighs these factors in comparative wear rates. My opinion and I am open to challenge.
On the second issue of mixing tyres. If anyone can prove to me that Porsche or indeed any member of this board has tested all possible combinations I will happily concede this issue. In reality Porsche's stance is probably based more upon a desire to avoid litigation than extensive testing of possible combinations. I personally would stick to the same front and rear, purely to stay within charted territory. However there is no way that I can make a mental leap to rule out the possibility that there are indeed different combinations that would result in improved performance with complete safety. I have neither the time or the money to find out!
To say nothing of the potential risk to my car.
With regard to the engine braking Jack I would strongly counsel a quick mental reminder to yourself of the price differential beween clutches and pads - I am firmly in the brakes are for slowing cars camp it's way cheaper in the long run!
Sorry for the length of this post but at least that's off my chest.
I will await the howls of derision!!! <img border="0" alt="[icon107]" title="" src="graemlins/icon107.gif" />
Some strong opinions here, and that is good everything has some sort of value if you think it through.
There seem to be two distinct issues here:-
1) The balance between front and rear wear rates.
2) The mixing of tyres front versus rear.
With regard to 1. No weight has been given to the fact that Jack runs a supercharged car putting significantly more horsepower through his rears. Also from what I can see Jack's car is used primarily if not excusively on the road.
I would agree that on a track I would expect the front/rear wear rates to be closer, to achieve this on the road would lead me to ask, even as someone who would class themselves as a fast road driver " Which is going to wear out the faster your tyres or your driving license!" I also doubt that Jack really meant that his fronts were near perfect but more that they were still perfectly usable and didn't require changing.
In a track environment the wear rates will still be affected by the set up of the car and particularly the balance between over/understeer.
I have significant track time myself primarily on bikes, but also in cars, my personal preference is of course to a set up favouring oversteer which will result in slightly higher rear rather than front wear rates.
Forget the track for a moment and return to a road environment and take an extreme example.
Modern Superbikes put real world rear wheel BHP figures of between 130/150 through a contact patch the size of a cigarette pack, braking is taken care of via a front wheel twin disc system with 6 piston calipers and pretty much race spec pads along with a basically redundant rear brake (the wheel isn't touching the floor in anything above 7/10ths braking). Front tyres carry extreme loads on turn in and under braking. Again you have a tiny contact patch and consequently compounds are way softer than car compounds.
I personally have worn out rear tyres on the road in less than 800 miles. I have never changed a front in less than 3000. Why? I would suggest that in a road environment big BHP through the rear has more opportunity to be used than huge cornering or braking forces and outweighs these factors in comparative wear rates. My opinion and I am open to challenge.
On the second issue of mixing tyres. If anyone can prove to me that Porsche or indeed any member of this board has tested all possible combinations I will happily concede this issue. In reality Porsche's stance is probably based more upon a desire to avoid litigation than extensive testing of possible combinations. I personally would stick to the same front and rear, purely to stay within charted territory. However there is no way that I can make a mental leap to rule out the possibility that there are indeed different combinations that would result in improved performance with complete safety. I have neither the time or the money to find out!
To say nothing of the potential risk to my car.
With regard to the engine braking Jack I would strongly counsel a quick mental reminder to yourself of the price differential beween clutches and pads - I am firmly in the brakes are for slowing cars camp it's way cheaper in the long run!
Sorry for the length of this post but at least that's off my chest.
I will await the howls of derision!!! <img border="0" alt="[icon107]" title="" src="graemlins/icon107.gif" />
01-26-2003, 09:37 AM
#22
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Sachin
</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva"> but hey winter is almost over right? </font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Yep, only four and a half more months!
As to the tire combo issue, if the engineers say don't, if there are many reports here and elsewhere about squirrelly behavior from different tires on the same car, why would you do it?
The only reason I can think of is someone's trying to save a buck. Why not sell the still good tires and put that money towards FOUR new ones.
Worst case scenario, but still our responsibility: the newbies who visit this board rely on the posters to know what they are talking about. If we make it sound ok to do this, someone could end up damaging his car or himself.
</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva"> but hey winter is almost over right? </font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Yep, only four and a half more months!
As to the tire combo issue, if the engineers say don't, if there are many reports here and elsewhere about squirrelly behavior from different tires on the same car, why would you do it?
The only reason I can think of is someone's trying to save a buck. Why not sell the still good tires and put that money towards FOUR new ones.
Worst case scenario, but still our responsibility: the newbies who visit this board rely on the posters to know what they are talking about. If we make it sound ok to do this, someone could end up damaging his car or himself.
01-26-2003, 10:35 AM
#23
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</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Originally posted by Mike in Chi:
<strong>The only reason I can think of is someone's trying to save a buck. Why not sell the still good tires and put that money towards FOUR new ones.
Worst case scenario, but still our responsibility: the newbies who visit this board rely on the posters to know what they are talking about. If we make it sound ok to do this, someone could end up damaging his car or himself.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Ed Zachary.
Sachin, restrained yowling about the dangers of mixing tires on a rear engined, high-performance car aside, I found myself in your situation a while back. I'd ponied up big money for a full set of S-02s. When the rears wore out (usual 2:1 wear rate), the replacement cost of a pair of rears was so high I looked for alternatives as well. I wasn't all that impressed w. the tires' dry traction anyway. I realized that I could take Ray Calvo's advice and buy a full set of RE-71s for damn near what two rear S-02s were going to cost.
For street driving, they're *fine*. For your first half-dozen track weekends, they're *fine*. And when you outgrow them for the track, buy a set of track wheels & mount R-compound on them. RE-71s are discontinued, but the RE-730s have been rev'ed to second generation to address road noise, and they're fine, too.
If you need more dry traction than RE-730s can deliver on the street, you need to a) slow the hell down, or b) get thee to a track! That's not really directed at you personally, just a general observation I like to share from time to time <img border="0" title="" alt="[Wink]" src="wink.gif" />
<strong>The only reason I can think of is someone's trying to save a buck. Why not sell the still good tires and put that money towards FOUR new ones.
Worst case scenario, but still our responsibility: the newbies who visit this board rely on the posters to know what they are talking about. If we make it sound ok to do this, someone could end up damaging his car or himself.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Ed Zachary.
Sachin, restrained yowling about the dangers of mixing tires on a rear engined, high-performance car aside, I found myself in your situation a while back. I'd ponied up big money for a full set of S-02s. When the rears wore out (usual 2:1 wear rate), the replacement cost of a pair of rears was so high I looked for alternatives as well. I wasn't all that impressed w. the tires' dry traction anyway. I realized that I could take Ray Calvo's advice and buy a full set of RE-71s for damn near what two rear S-02s were going to cost.
For street driving, they're *fine*. For your first half-dozen track weekends, they're *fine*. And when you outgrow them for the track, buy a set of track wheels & mount R-compound on them. RE-71s are discontinued, but the RE-730s have been rev'ed to second generation to address road noise, and they're fine, too.
If you need more dry traction than RE-730s can deliver on the street, you need to a) slow the hell down, or b) get thee to a track! That's not really directed at you personally, just a general observation I like to share from time to time <img border="0" title="" alt="[Wink]" src="wink.gif" />
01-26-2003, 10:56 AM
#24
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</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Originally posted by ca993twin:
<strong>Matt,
Sorry for the abbreviation. Substitute "handles well with aggressive driving" for my "works well". I am an experienced track driver, and I like this particular combo. I drove another TT today that had S02s all around, and it also "worked well". But it also had a lot more suspension work done to it than mine.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">I too have S03's on my car, coming from S02's, and think they are a great street tire. My main reason for going with the S03 was due to the better wet traction over the S02. I do wish the new S03 had the feedback of the old tire but I guess we can't have it all!
<strong>Matt,
Sorry for the abbreviation. Substitute "handles well with aggressive driving" for my "works well". I am an experienced track driver, and I like this particular combo. I drove another TT today that had S02s all around, and it also "worked well". But it also had a lot more suspension work done to it than mine.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">I too have S03's on my car, coming from S02's, and think they are a great street tire. My main reason for going with the S03 was due to the better wet traction over the S02. I do wish the new S03 had the feedback of the old tire but I guess we can't have it all!
01-26-2003, 12:22 PM
#25
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The Pirelli P-zero system was designed as such,a system, for specific weight/drive combinations. Apples and grapefruit comparison.
01-26-2003, 12:27 PM
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</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Originally posted by Jack Ennuste:
<strong>About different tread front/rear.
Pirelli recommends different tires:
Pzero Rosso Assimmetrico back
PZero Direzionale front
(Very different treads).
Or You can put all 4 asimmetricos if you like.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Jack
1. The PZero Rosso and the PZero are two different models & Pirelli does NOT recommend mixing them.
2. For either PZero model, the Direzionale and the Asimmetrico are, according to Pirelli, "designed for use in tandem, or separately, according to the type of car, conditions of use and driving style," as opposed to a haphazard combination of just any two tire brands/models.
3. Using the PZero system as a tacit authoritative endorsement for mixing tires on our cars is both misleading & irresponsible to those who rely upon this board for sound advice.
</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Originally posted by Tim Ashfield:
<strong>If anyone can prove to me that Porsche or indeed any member of this board has tested all possible combinations I will happily concede this issue. In reality Porsche's stance is probably based more upon a desire to avoid litigation than extensive testing of possible combinations.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">So are you suggesting that readers of this board resolve the unknowns by mixing tires & reporting back which combinations put them into a wall at the limit (e.g., an emergency evasive maneuver)?
I agree that Porsche's proscription against mixing tires is based "upon a desire to avoid litigation," since it would be negligent for Porsche (or posters here) to suggest that mixing tires is safe. An elemental understanding of tire and vehicle design & dynamics suggests mixing tires is far more likely to be bad than good - no testing required.
I've never read nor heard of any tire manufacturer, tire dealer or car maker endorsing mixed tires. I've mixed tires in the past on other cars due to economic necessity & always found it to result in less (sometimes far less) than acceptable handling.
I'm puzzled & concerned by this thread. Rennlist has traditionally been a source of sound, reliable and responsible guidance and information. I hope that remains & confusing or erroneous posts continue to be challenged. All, of course, IMVHO.
<strong>About different tread front/rear.
Pirelli recommends different tires:
Pzero Rosso Assimmetrico back
PZero Direzionale front
(Very different treads).
Or You can put all 4 asimmetricos if you like.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Jack
1. The PZero Rosso and the PZero are two different models & Pirelli does NOT recommend mixing them.
2. For either PZero model, the Direzionale and the Asimmetrico are, according to Pirelli, "designed for use in tandem, or separately, according to the type of car, conditions of use and driving style," as opposed to a haphazard combination of just any two tire brands/models.
3. Using the PZero system as a tacit authoritative endorsement for mixing tires on our cars is both misleading & irresponsible to those who rely upon this board for sound advice.
</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Originally posted by Tim Ashfield:
<strong>If anyone can prove to me that Porsche or indeed any member of this board has tested all possible combinations I will happily concede this issue. In reality Porsche's stance is probably based more upon a desire to avoid litigation than extensive testing of possible combinations.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">So are you suggesting that readers of this board resolve the unknowns by mixing tires & reporting back which combinations put them into a wall at the limit (e.g., an emergency evasive maneuver)?
I agree that Porsche's proscription against mixing tires is based "upon a desire to avoid litigation," since it would be negligent for Porsche (or posters here) to suggest that mixing tires is safe. An elemental understanding of tire and vehicle design & dynamics suggests mixing tires is far more likely to be bad than good - no testing required.
I've never read nor heard of any tire manufacturer, tire dealer or car maker endorsing mixed tires. I've mixed tires in the past on other cars due to economic necessity & always found it to result in less (sometimes far less) than acceptable handling.
I'm puzzled & concerned by this thread. Rennlist has traditionally been a source of sound, reliable and responsible guidance and information. I hope that remains & confusing or erroneous posts continue to be challenged. All, of course, IMVHO.
01-26-2003, 12:35 PM
#29
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Robert,
I did some checking. I have a C4S and I can find the fronts in the RE730s 225-40 18" but can't find the rears in RE730s 285-30 18"
I did some checking. I have a C4S and I can find the fronts in the RE730s 225-40 18" but can't find the rears in RE730s 285-30 18"
01-26-2003, 12:47 PM
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</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Originally posted by Jack Ennuste:
<strong>About different tread front/rear.
Pirelli recommends different tires:
Pzero Rosso Assimmetrico back
PZero Direzionale front
(Very different treads).
Or You can put all 4 asimmetricos if you like.
The PZero Rosso Direzionale is designed to offer enhanced hydroplaning resistance and is primarily for use on the lighter load carrying front axle positions of mid-engined and rear-engined rear-wheel-drive cars (which are combined with The PZero Rosso Asimmetrico tires on the rear axle positions).
<a href="http://www.tirerack.com/tires/tires.jsp?tireMake=Pirelli&tireModel=PZero+Rosso+Asimmetrico" target="_blank">Pirelli PZero</a>
Chris: I totally agree regarding tire pressure differences and think that it's essential.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">While you are right Jack about the P-Zero's dont forget that this is a package, hence the P-Zero "system". In this case certain characteristics (compound, stracture of the tire etc) are the same, so the tread design which is different will give different characteristics according to your needs. Street driving you will use the combo for better wet traction, track or dry driving you will use same assyms front and back for better "stick".
Mix matching tires is dangerous, that goes for size, compounds etc. I have had several experiences with mix matched tires.
1. When I was in college I had a 924. Since the money was very tight as you can appreciate I could not afford much. When the time came to change my rear tires I dished money for a different set than the fronts, same brand ( goodyears)but 50 bucks cheaper . I thought what can really happen... There is this 90 degree turn that led to the street next to the dorm's I use to be. I had taken that turn sooo many times , it was a fun 2nd gear turn with safe "exit points" (grass and plenty space) so I knew it blindly. One fine day about a couple of weeks after the new tires were on, without traffic on the turn I gave it my usual go... I was crossed up so fast I could not believe it! That safe exit point came very handy as I got so much "tank slapping" that before I knew it I was plowing the grass...
2. When I bought my 968 the previous owner who was clueless about the car left had switched the fronts with the backs " to rotate" the tires for me! I did not know that he did this and when I picked up the car from him I did not pay attention to this as I had previously inspected the car thoroughly. So I drive it off his subdivision I feel the steering sooo light, I'm thinking "what the hell" this is not right. Here I an at the traffic light first, having to make a left turn, I give it a very mild go and I' sideways in the middle of the turn!!! This was so bizarre I thought there must be something seriously wrong with this car... Took it to the dealer that had done the PPI and he started laughing...Needless to say when all tires came back to their proper place the car was literally transformed, steering came back to "normal" nice and weighted and the car felt 200% different.
3. In Maui I had rented a very tired Boxster. When I inspected the car I saw the mix matched tires, I was worried but I figured its Maui where acn you run the car hard? Besides that was not the point of renting the Boxster, my wife and I wanted to enjoy the "porsche sound" and drop down experience on this beautifull island. Coming back from an incredible dinner at the Grand Wailea a random idiot cross a red light, I was doing maybe 40mph had to brake hard and turn to the right to avoid him. At that ridiculous speed I got sideways and thank God I did not hit anything. I highly doubt that if the car was properly shod I would have had that happen to me.
In short I will never mix match, plan for these changes financially and for sure ask if you need tires here, for example in a few days I will have a set of front P_Zeros in new condition ready for sale and a set of front Pilot SX MXX3 Michellin's to give away with plenty of tread remaining...Last year I gave away a set of rear S0'2s...
<strong>About different tread front/rear.
Pirelli recommends different tires:
Pzero Rosso Assimmetrico back
PZero Direzionale front
(Very different treads).
Or You can put all 4 asimmetricos if you like.
The PZero Rosso Direzionale is designed to offer enhanced hydroplaning resistance and is primarily for use on the lighter load carrying front axle positions of mid-engined and rear-engined rear-wheel-drive cars (which are combined with The PZero Rosso Asimmetrico tires on the rear axle positions).
<a href="http://www.tirerack.com/tires/tires.jsp?tireMake=Pirelli&tireModel=PZero+Rosso+Asimmetrico" target="_blank">Pirelli PZero</a>
Chris: I totally agree regarding tire pressure differences and think that it's essential.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">While you are right Jack about the P-Zero's dont forget that this is a package, hence the P-Zero "system". In this case certain characteristics (compound, stracture of the tire etc) are the same, so the tread design which is different will give different characteristics according to your needs. Street driving you will use the combo for better wet traction, track or dry driving you will use same assyms front and back for better "stick".
Mix matching tires is dangerous, that goes for size, compounds etc. I have had several experiences with mix matched tires.
1. When I was in college I had a 924. Since the money was very tight as you can appreciate I could not afford much. When the time came to change my rear tires I dished money for a different set than the fronts, same brand ( goodyears)but 50 bucks cheaper . I thought what can really happen... There is this 90 degree turn that led to the street next to the dorm's I use to be. I had taken that turn sooo many times , it was a fun 2nd gear turn with safe "exit points" (grass and plenty space) so I knew it blindly. One fine day about a couple of weeks after the new tires were on, without traffic on the turn I gave it my usual go... I was crossed up so fast I could not believe it! That safe exit point came very handy as I got so much "tank slapping" that before I knew it I was plowing the grass...
2. When I bought my 968 the previous owner who was clueless about the car left had switched the fronts with the backs " to rotate" the tires for me! I did not know that he did this and when I picked up the car from him I did not pay attention to this as I had previously inspected the car thoroughly. So I drive it off his subdivision I feel the steering sooo light, I'm thinking "what the hell" this is not right. Here I an at the traffic light first, having to make a left turn, I give it a very mild go and I' sideways in the middle of the turn!!! This was so bizarre I thought there must be something seriously wrong with this car... Took it to the dealer that had done the PPI and he started laughing...Needless to say when all tires came back to their proper place the car was literally transformed, steering came back to "normal" nice and weighted and the car felt 200% different.
3. In Maui I had rented a very tired Boxster. When I inspected the car I saw the mix matched tires, I was worried but I figured its Maui where acn you run the car hard? Besides that was not the point of renting the Boxster, my wife and I wanted to enjoy the "porsche sound" and drop down experience on this beautifull island. Coming back from an incredible dinner at the Grand Wailea a random idiot cross a red light, I was doing maybe 40mph had to brake hard and turn to the right to avoid him. At that ridiculous speed I got sideways and thank God I did not hit anything. I highly doubt that if the car was properly shod I would have had that happen to me.
In short I will never mix match, plan for these changes financially and for sure ask if you need tires here, for example in a few days I will have a set of front P_Zeros in new condition ready for sale and a set of front Pilot SX MXX3 Michellin's to give away with plenty of tread remaining...Last year I gave away a set of rear S0'2s...