gt4 factory tires = continental?
08-12-2021, 02:12 AM
#16
Congratulations, @tshih you learned the hard way that most Porsches are not delivered with an alignment that promotes tire longevity at the track. There are quite a few threads here about it. I support a fellow in a Focus RS who had the same delamination with Goodyear Supercup 3s because he's running in the Stock class and can't get any more negative camber out of his OEM suspension. I suspect you'll have similar wear / delamination from your Contis (or any other tire) unless you adjust your alignment.
Fortunately, your car has more negative camber available to it—all you need to do is have the OEM suspension components better adjusted for the track. Within what the OEM components allow you aren't going to get to any settings that destroy the streetability of the car (assuming you don't do something wild with the toe). Most folks can get around -1.6° of camber at the rear, and depending on your preference, you can run -1.8° to -2.1° of camber at the front by maxing-out the adjustment at the top of the strut tower and adding shims to your lower control arms. Stick to the stock toe settings and these mild camber settings aren't going to do anything negative to your streetability, but they'll definitely help even out your tire wear.
Thanks for being an instructor with so many groups!
Fortunately, your car has more negative camber available to it—all you need to do is have the OEM suspension components better adjusted for the track. Within what the OEM components allow you aren't going to get to any settings that destroy the streetability of the car (assuming you don't do something wild with the toe). Most folks can get around -1.6° of camber at the rear, and depending on your preference, you can run -1.8° to -2.1° of camber at the front by maxing-out the adjustment at the top of the strut tower and adding shims to your lower control arms. Stick to the stock toe settings and these mild camber settings aren't going to do anything negative to your streetability, but they'll definitely help even out your tire wear.
Thanks for being an instructor with so many groups!
One thing I found out was that plates are not to be used on 718s (at least not on GT4s/Spyders) per Porsche. Service bulletin/manual exact quote: Front-axle camber setting: The camber adjustment on the front axle on the Cayman GT4/Spyder is performed only via the supporting mount. The intermediate plates -Arrow- on the 2-part wishbone must not be changed, as this can result in an impermissible wheel overlap at the wheel housing. Maybe this is just CYA from Porsche? I don't know but I'll leave mine at the max reachable without plates for now.
As for track day tire life, at this point I think I'll be lucky to get 300 to 350 miles but maybe it'll get a little better. (My make-a-wish.) So far on the new GT4 I've gotten about 270 miles on a set of Pilot Sport Cup 2s and the same on a set of Dunlop Sort Max Race 2s. One of my Dunlop fronts de-laminated badly same as the one in the OP's pic. I'm back to the PSC2s at the moment which I think may be better tires. Time will tell.
Correct track-use alignment will help tremendously. As someone mentioned earlier in this thread, the term "proper alignment" on a new Porsche at delivery is probably an oxymoron. Alignments could be all over the map at each corner when the car gets off the boat.
Last edited by blueline106; 08-12-2021 at 09:56 AM.
08-12-2021, 02:58 PM
#18
Or maybe alignments are not all that precise from the factory. I think their acceptable parameters are generous. Mine was off at the start and others have been too. In any case, I think it's wise to have alignment checked on new vehicles as part of the pre-delivery process whether one is going to track a car or not. Can't hurt. High-end tires aren't cheap.
08-12-2021, 03:25 PM
#19
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That's logical but then again, given the fact that they tie cars down tightly and huge container vessels can still heave around, it's not inconceivable that alignments could change.
Or maybe alignments are not all that precise from the factory. I think their acceptable parameters are generous. Mine was off at the start and others have been too. In any case, I think it's wise to have alignment checked on new vehicles as part of the pre-delivery process whether one is going to track a car or not. Can't hurt. High-end tires aren't cheap.
Or maybe alignments are not all that precise from the factory. I think their acceptable parameters are generous. Mine was off at the start and others have been too. In any case, I think it's wise to have alignment checked on new vehicles as part of the pre-delivery process whether one is going to track a car or not. Can't hurt. High-end tires aren't cheap.
. I'm not saying people shouldn't get a track alignment before tracking or auto-x. 
08-12-2021, 04:56 PM
#20
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08-12-2021, 05:41 PM
#21
Beyond whether shops are good or bad, considering the abuse taken by the running gear of any car/truck these days I'd always encourage trying to maintain proper alignment if you care about tire wear, suspension components, car control...
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Westcoast (08-12-2021)
08-12-2021, 06:46 PM
#22
Burning Brakes
These cars are not given a proper wheel alignment at the factory. I'm not aware of any automaker that does this. It would not make sense for car makers to do this on a freshly assembled vehicle because the alignment can change dramatically as the car suspension settles under its own weight..
The suspensions are slapped together on the line. And if anything, they may get a cursory alignment check and tweak just to make sure that nothing is completely out of whack or unsafe. But If your car came perfectly aligned from the factory, it was pure luck, not quality control.
Our cars in particular were all assembled with spacers in the suspension to lift the ride height from the factory for goodness sake! How would they even try to align the suspension like that that!?
My GT4 came with an alignment completely out of spec to the point where I suspect it was not aligned by Porsche at all. For example one of the front strut mounts was set to max camber while the other side front mount was set to nearly minimum camber. BTW this particular strut mount camber setting is not even something that you need a laser alignment rack to see. A basic visual quality inspection should have caught how off my car's alignment was from the factory.
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GTChamp (08-17-2021)
08-12-2021, 08:46 PM
#23
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I didn't fully understand the anti-local alignment shops post either. Porsche dealer here is phenomenal and I know of several other shops and techs in my area using proper up-to-date equipment who are competent and know what they are doing. They all care about the quality of their work. Maybe it's bad where he lives.
Beyond whether shops are good or bad, considering the abuse taken by the running gear of any car/truck these days I'd always encourage trying to maintain proper alignment if you care about tire wear, suspension components, car control...
Beyond whether shops are good or bad, considering the abuse taken by the running gear of any car/truck these days I'd always encourage trying to maintain proper alignment if you care about tire wear, suspension components, car control...
These cars are not given a proper wheel alignment at the factory. I'm not aware of any automaker that does this. It would not make sense for car makers to do this on a freshly assembled vehicle because the alignment can change dramatically as the car suspension settles under its own weight..
The suspensions are slapped together on the line. And if anything, they may get a cursory alignment check and tweak just to make sure that nothing is completely out of whack or unsafe. But If your car came perfectly aligned from the factory, it was pure luck, not quality control.
Our cars in particular were all assembled with spacers in the suspension to lift the ride height from the factory for goodness sake! How would they even try to align the suspension like that that!?
My GT4 came with an alignment completely out of spec to the point where I suspect it was not aligned by Porsche at all. For example one of the front strut mounts was set to max camber while the other side front mount was set to nearly minimum camber. BTW this particular strut mount camber setting is not even something that you need a laser alignment rack to see. A basic visual quality inspection should have caught how off my car's alignment was from the factory.
The suspensions are slapped together on the line. And if anything, they may get a cursory alignment check and tweak just to make sure that nothing is completely out of whack or unsafe. But If your car came perfectly aligned from the factory, it was pure luck, not quality control.
Our cars in particular were all assembled with spacers in the suspension to lift the ride height from the factory for goodness sake! How would they even try to align the suspension like that that!?
My GT4 came with an alignment completely out of spec to the point where I suspect it was not aligned by Porsche at all. For example one of the front strut mounts was set to max camber while the other side front mount was set to nearly minimum camber. BTW this particular strut mount camber setting is not even something that you need a laser alignment rack to see. A basic visual quality inspection should have caught how off my car's alignment was from the factory.
08-12-2021, 08:57 PM
#24
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Zhao is totally correct in his assessment of the tires being overheated. Being that I took it to the track at 600 miles (street break-in) and being mindful of the get acquainted period I wasn't putting the car through a severe test of its limits.I drove the car on November 7,8 last year at Thunderbolt starting at 29psi front and 33 psi rears (standard street tire cold specs) and there were no issues. Then the next 2 days were in March of this year and still no issues. It was only in April with BMWCCA that on the 5th track day that I noticed the tire pressures were over 41 psi (normally the fronts should be at 34 and rears at 36 when hot) and saw the delamination in photos posted. Others who ran the 981 GT4 have also suggested getting more neg. camber (1.75 deg front and 2.5 rears) to get better more even wear. My personal philosophy when it comes to changing from OEM settings on Porsche GT cars is the factory engineers deliver a product meant for the owner's intended use. These GT# cars are meant to be driven to and from the tracks and provide a high performance experience that's comparable to a dedicated track/race car with the comforts of A/C and suspension (PASM) settings. Those that want to turn the street optimized settings to track /race car have the means to adjust the suspension and ATRB on these GT# cars to their liking.
I have always run the OEM alignment settings on all the cars I track (2010 GT3 and 2020 718 GT4) using Porsche N0 or N1 tires along with the Continentals Extreme contact Sport (which were the least expensive and most durable option). Those tires have never exhibited the kind of overheating and delamination seen with the Dunlop Racemax2 front tires. I have also always worn the tires down to the chords before replacement.
Last edited by Five12Free; 08-13-2021 at 04:24 PM.
08-12-2021, 09:27 PM
#25
And how do you know your factory alignments weren't (or aren't) wacky? I ask because the gist of your comments is that you didn't feel the need to check factory alignment and also that you presumably don't realign because the locals where you live don't know what they are doing.
By the way, some of the other posters' comments effectively shoot down your theory of great factory alignments. How do you just ignore those observations? It's not at all a matter of being lucky or unlucky with factory alignments. They are iffy. Period. Rather, it's a matter of checking and affirming whether the alignments are set correctly or not. Your many dozens of new cars probably had (or have) shot alignments but since you presumably don't have them checked, you would never have known.
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lowbee (08-12-2021)
08-13-2021, 01:09 PM
#26
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And how do you know your factory alignments weren't (or aren't) wacky? I ask because the gist of your comments is that you didn't feel the need to check factory alignment and also that you presumably don't realign because the locals where you live don't know what they are doing.
Yes I do live in Canada, 6 Porsche Dealers (soon to be 7) within 90 minutes from my front door. lol.By the way, some of the other posters' comments effectively shoot down your theory of great factory alignments. How do you just ignore those observations? It's not at all a matter of being lucky or unlucky with factory alignments. They are iffy. Period. Rather, it's a matter of checking and affirming whether the alignments are set correctly or not. Your many dozens of new cars probably had (or have) shot alignments but since you presumably don't have them checked, you would never have known.
08-13-2021, 01:28 PM
#27
Well I guess it all depends what one calls an acceptable OEM alignment. Everything on my GT4 was in the red. For example camber was to be 1.5 on all 4 corners; it ranged from 1.4 to 1.7 - none in the green. Toe was red on all 4 corners as well.
08-13-2021, 04:04 PM
#28
Hmm, I guess you misread what I said ..."I'm not saying people shouldn't get a track alignment before tracking or auto-x". FWIW, I have about 25 years of every weekend competition experience track and auto-x and I have track aligned all my cars as well as those of some of my racing buddies. And you ...?
If a new street car is out of factory spec its usually self evident and likely due to damaged component(s). IMO, there's no need to have your new car (street) aligned unless something has caused it to be out of spec. I think there's plenty of "locals where I live" that know what they're doing. Yes I do live in Canada, 6 Porsche Dealers (soon to be 7) within 90 minutes from my front door. lol.
I never said factory alignments are great for track use, only that they're suitable for street use and do not normally need to be checked when new or re-aligned when new. I'm confident the new cars I've owned haven't had "shot" alignments. lol! If you feel the need to check the alignment of your new cars, have at it.
If a new street car is out of factory spec its usually self evident and likely due to damaged component(s). IMO, there's no need to have your new car (street) aligned unless something has caused it to be out of spec. I think there's plenty of "locals where I live" that know what they're doing.
Yes I do live in Canada, 6 Porsche Dealers (soon to be 7) within 90 minutes from my front door. lol.I never said factory alignments are great for track use, only that they're suitable for street use and do not normally need to be checked when new or re-aligned when new. I'm confident the new cars I've owned haven't had "shot" alignments. lol! If you feel the need to check the alignment of your new cars, have at it.
If you accept the factory settings, you are not getting the best from your sports car. If I am spending that much on a sports car, I want it optimized, but that's just me.
Last edited by TRZ06; 08-13-2021 at 04:05 PM.
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Z06jerry (08-13-2021)
08-17-2021, 03:44 AM
#29
Chiming in on alignment. My 718 GT4 was handed over to me with really bad alignment - no idea whether it was like that from the factory, from the cargo ship, or from the dealer's PDI. Either way there was so much thrust angle the car felt really unstable even on straight city streets at street speeds. I ended up taking it to a full race shop to have it aligned, replacing the rear toe links at the same time. Alignment is very stable now (-2F / -1.5R / 2.2mm rear toe-in)