Major Disappointment With PSS vs PS2
07-16-2012, 07:22 PM
#31
Burning Brakes
Yes, I would say that is decent change to shoot for. Remember there are 60' in a degree, so 0.5° is 30' and 0.1° is 6'. 10' is not much, scrub or wear wise, just like jordanturbo said, but adds a lot to tracking, IMHO. If you ask for that and -45' camber, I think you will notice the difference.
07-16-2012, 08:40 PM
#32
Former Vendor
I did speak with him last week and recommended a closer look into alignment also, as the PSS has received overwhelmingly good reviews. I'm very grateful you guys "in the know" can help out so much with recommendations!
07-16-2012, 10:03 PM
#33
Three Wheelin'
many have complained about the sidewall flex of the PSS and the lack of "feel".... it's quite common among aggressive drivers.... go with Bridgestone S04... they have better feel and stronger sidewall
07-16-2012, 11:35 PM
#34
Drifting
The OEM sizes for early 996 C4's with 18" wheels were 225/40-18 front and 265/35-18 rear. I ran 235/40-18 front and 265/40-18 PS2's (997 sizing) for years with no problems even though the diameter difference was larger than the OEM fitting. With the PSS I went back to the OEM fitting (which I always ran with my winter tires).
Sites like Tirerack have tables that show the revs per mile and I did extensive comparisons of different tire combinations to see how much percentage difference there was in rotations per mile when looking at alternate sizes. I have not done it for the sizes you are running, but you might want to.
If the later 996 rear sizing (285/30-18) had been available in the PSS I might have gone to them.
Sites like Tirerack have tables that show the revs per mile and I did extensive comparisons of different tire combinations to see how much percentage difference there was in rotations per mile when looking at alternate sizes. I have not done it for the sizes you are running, but you might want to.
If the later 996 rear sizing (285/30-18) had been available in the PSS I might have gone to them.
07-17-2012, 01:08 AM
#35
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Yes, I was going by memory, but really, 0 toe and 6' is at the splitting hair line. The tech would shoot for 0 or 10' and then if over or under, do another small adjustment to correct, and get it closer. Just rotating the wheel is likely to change a few seconds. I think the dealer might give you a strange look if you ask for 6' of toe on each side. It is unfortunately, not that easy to dial in that kind of accuracy. For instance, you have -38' camber on one side, IIRC, so the tech is not going to touch it to try for -40'. You can't adjust the strut plate bolts/nuts that little. Just tightening the nuts moves the strut a few seconds. The other side, he would bump in, and get closer because it is a decent amount off. Doesn't hurt to explain what you are trying to achieve, and get their suggestions, too, especially if they are a Porsche shop. And personally, I think front neg camber causes little wear compared to toe, especially for the turn in and corner stability benefit, so I think those are good numbers. I think you will find the "new" as found numbers will have changed a little since the as left. Make sure you have the tires inflated to where you think they are best handling, now. How many miles on the tires now? Also, and this is a long shot, you might have a defective tire. I had a new Michelin (a few years back, different car) with a separated belt, that was not easy to find, and the car was very squirrely until they figured out what it was. Only problem is that the way we found it was to rotate the tires front to back, one at a time, and pin point which tire it was, which we obviously can't do on the 996.
Is 245/40-18F and 275/35-18R standard for MKI C4? That just seems a lot larger F/R compared to my C2 where 18" standard is 225/40 and 285/30, as your fronts are 16mm taller and rears are 21.5mm taller than mine. Rough calcs show you went in the right direction for sure, as yours are less than .5% F/R difference where mine is 3.4% smaller circumference and has a 1% F/R differential. The previous tire son my car, the Sumi HRTZ-IIs had an even larger F/R difference.
Is 245/40-18F and 275/35-18R standard for MKI C4? That just seems a lot larger F/R compared to my C2 where 18" standard is 225/40 and 285/30, as your fronts are 16mm taller and rears are 21.5mm taller than mine. Rough calcs show you went in the right direction for sure, as yours are less than .5% F/R difference where mine is 3.4% smaller circumference and has a 1% F/R differential. The previous tire son my car, the Sumi HRTZ-IIs had an even larger F/R difference.
Good point, very few if any shops will take the precision that I do when Aligning or maintaining their vehicles in general than I do with my own vehicle in my own shop with my own equipment. When I was adjusting my toe I would take it in to .10 Then go back a c**t hair, then on the locking bolt a little hard to get it down to that 0.06 that I was looking for. Again for camber just tightening that adjustment bolt will affect it that little bit. I think when I last did my alignment it took me close to 3 hours to get it exactly perfect the way I wanted.
I would suggest asking the people doing your alignment to shoot for 0.10 in the rear then tap it back a c**t hair.
07-17-2012, 04:36 AM
#37
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haha I kid, I kid
Last edited by jordanturbo; 07-17-2012 at 04:56 AM.
07-17-2012, 04:55 AM
#38
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Maybe of Goodyear gets their s**t together and starts offering a larger size range in their new Asymmetric 2 in a broader size range the I will be able to try them out and recommend them like I recommend the PSS, From the Asymmetric 2's I have sold, they have gotten pretty good reviews.
07-17-2012, 12:14 PM
#39
Burning Brakes
I believe the correct term is CRCH, not c**t hair...lol...
Based on what Dharn says, then you are running pretty wide fronts and in between wide rears, so you will have a more oversteer than stock, coupled with a beefier front ARB and springs, adds still more oversteer, so you will be very alignment sensitive. Personally, I figured that Porsche knew what sizes worked best, and while I don't have any issue going +1 F&R, it appears to me that Porsche wanted to reduce over steer by changing the rear to 285/30-18 in later cars, and going with a slightly smaller than front circumference, which increases torque slightly as well, with 10" wide 18"rims, and keeping the fronts the same. The OP has gone in the opposite direction (unintentionally, as he was duplicating the sizes previously on the car, but matching F&R circumferences), so it will be a different handling car, for sure, more sensitive to alignment and pressure.
Interesting that jordanturbo liked the Dunlop Sport Maxx over the PS2s, as I had them on a previous BMW, rather than pay the high prcie for PS2, and my initial impressions were very positive, but soured after about 8-12k miles. I hate when the character of a tire changes greatly over it's wear life, something the Michelins seem to do better than most others. That was my second set of higher performance Dunlops, that did the same thing, so I swore I would stick with Michelins after that. Of course, since PS2s on Porsches are not rotatable, they only give them a 10kmile warranty, so I may be eating my words next year!
Based on what Dharn says, then you are running pretty wide fronts and in between wide rears, so you will have a more oversteer than stock, coupled with a beefier front ARB and springs, adds still more oversteer, so you will be very alignment sensitive. Personally, I figured that Porsche knew what sizes worked best, and while I don't have any issue going +1 F&R, it appears to me that Porsche wanted to reduce over steer by changing the rear to 285/30-18 in later cars, and going with a slightly smaller than front circumference, which increases torque slightly as well, with 10" wide 18"rims, and keeping the fronts the same. The OP has gone in the opposite direction (unintentionally, as he was duplicating the sizes previously on the car, but matching F&R circumferences), so it will be a different handling car, for sure, more sensitive to alignment and pressure.
Interesting that jordanturbo liked the Dunlop Sport Maxx over the PS2s, as I had them on a previous BMW, rather than pay the high prcie for PS2, and my initial impressions were very positive, but soured after about 8-12k miles. I hate when the character of a tire changes greatly over it's wear life, something the Michelins seem to do better than most others. That was my second set of higher performance Dunlops, that did the same thing, so I swore I would stick with Michelins after that. Of course, since PS2s on Porsches are not rotatable, they only give them a 10kmile warranty, so I may be eating my words next year!
07-17-2012, 01:09 PM
#40
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Interesting that jordanturbo liked the Dunlop Sport Maxx over the PS2s, as I had them on a previous BMW, rather than pay the high prcie for PS2, and my initial impressions were very positive, but soured after about 8-12k miles. I hate when the character of a tire changes greatly over it's wear life, something the Michelins seem to do better than most others. That was my second set of higher performance Dunlops, that did the same thing, so I swore I would stick with Michelins after that. Of course, since PS2s on Porsches are not rotatable, they only give them a 10kmile warranty, so I may be eating my words next year!
07-17-2012, 01:39 PM
#41
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No problem, having my own brick and mortar tire shop up here I feel that I have unique insight on certain aspects concerning tires alignments and some other mechanical issues. Even though my shop is primarily a Goodyear dealer (aka goodyear authorized, not in others), I do not hesitate recommending the best product that suits the need of the customer, even if it is not a Goodyear product. The Michelin Pilot Super Sport is a great product, I would hate to see someone get rid of the best suited tire for their needs because of and issue un tire related. Before I had awesome luck with the Dunlop Sport Maxx GT, preferred them to the PS2's I had previously especially at their price point, but now when it is available it is hard not to recommend the PSS.
Maybe of Goodyear gets their s**t together and starts offering a larger size range in their new Asymmetric 2 in a broader size range the I will be able to try them out and recommend them like I recommend the PSS, From the Asymmetric 2's I have sold, they have gotten pretty good reviews.
Maybe of Goodyear gets their s**t together and starts offering a larger size range in their new Asymmetric 2 in a broader size range the I will be able to try them out and recommend them like I recommend the PSS, From the Asymmetric 2's I have sold, they have gotten pretty good reviews.
07-17-2012, 02:03 PM
#42
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Jordan
07-18-2012, 01:52 PM
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07-18-2012, 01:59 PM
#44
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07-18-2012, 07:26 PM
#45
Rocky Mountain High
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All of this discussion just shows how important it is to have your 996 aligned by a dealer or a shop who knows how to properly align Porsches.