OEM 20" GT4 Bridgestone RE-71R status
08-03-2016, 05:37 PM
#31
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08-03-2016, 06:01 PM
#33
Drifting
Maybe Bridgestone figures that GT3 and Turbo guys are less sensitive to the expected price gap between the RE-71R and the Cup 2 and that therefore even though the theoretical market may be larger, the actual market would be smaller? The Turbo also comes with more DD-friendly tires than the GT cars, which makes sense for its marketed use, so I don't know how many Turbo owners would consider the RE-71R with its harsher, louder ride and faster wear rate an overall upgrade.
Then there's the fact that the RS got N1-spec Cup 2s that are apparently a big improvement, so they might be worried that if Michelin/Porsche decides to spread the love, the next obvious recipient would be the GT3.
Then there's the fact that the RS got N1-spec Cup 2s that are apparently a big improvement, so they might be worried that if Michelin/Porsche decides to spread the love, the next obvious recipient would be the GT3.
08-03-2016, 06:23 PM
#34
Thanks for the update Damon. I'm considering these tires in OEM 981 GTS sizing. I can do 245/35/20 on the front and 285/35/20 on the back, however a 275 or 265 rear width would be better. Is there any information on future 265/35/20 or 275/35/20 sizes?
08-03-2016, 07:45 PM
#35
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may try the 265 and 305 19's on my 991 GT3...
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08-03-2016, 08:08 PM
#36
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Drivers that push harder are more likely to have a timer, to begin with. They are both an effect of a predisposed mindset going into the situation,with increased competitive psychological characteristics.
That aside, there's absolutely nothing wrong with hitting the track without a timer. Hell, I have Harrys Laptimer and don't even run it half the time.
08-05-2016, 05:58 PM
#37
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I would like to try that combo myself, but the diameter of the 265-35-19 is 26.3", and the expected diameter of the 305-30-19 is also 26.3". The stock setup on the 991 GT3 has the 245 fronts at 26.8" diameter and the 305 rears at 27.2", a difference of .4" from F-R. I am wondering if running the same diameter F & R would freak out the onboard computers? I guess the only way to know is to try it, but I sure wish they would make a 315 or 325/30-19 at about 26.7" diameter to go with the 265 fronts.
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08-05-2016, 06:39 PM
#38
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Thread Starter
997 cars used an overall diameter difference of about 3/4". The 991 is at about .4" I wish I knew for sure, but I would bet the computers are seeing that smaller difference.
08-05-2016, 09:28 PM
#39
Hi Damon, the porsche tech folks I have talked to about the
electronics and tire diameter differences have told me the
car will adapt/tolerate a significant difference. The example
they gave me was for the GT4 context. They say that all the
electronics for the GT4 and the GT4 clubsport versions are
identical, and the difference in front/rear diameters on the
clubsport tires is much more than for the standard GT4.
The standard GT4 Michelins differ only by 0.2" diameter, but
the 18" Michelin slicks for the Clubsport differ by 39mm! (1.5").
electronics and tire diameter differences have told me the
car will adapt/tolerate a significant difference. The example
they gave me was for the GT4 context. They say that all the
electronics for the GT4 and the GT4 clubsport versions are
identical, and the difference in front/rear diameters on the
clubsport tires is much more than for the standard GT4.
The standard GT4 Michelins differ only by 0.2" diameter, but
the 18" Michelin slicks for the Clubsport differ by 39mm! (1.5").
08-16-2016, 06:34 PM
#40
This is an update to the status of the release of Bridgestone RE-71R in OEM 20" GT4 sizes. At the release of these new sizes our estimate was early August for estimated arrival. I was able to speak with our Bridgestone rep yesterday and received the most up to date information we have on the status of both sizes. The front tires (245/35 20) are on the way from Japan to the US now, and the 3rd week of August is the estimate we now have for their arrival to our doors. The rears (295/30 20) are still being produced. At this time they are hoping to have them in the US approximately the first of September. I'll keep you updated as I get more information from Bridgestone. As a reminder, if you would like to pre-order the tires and get your name on the list for them, we will be happy to do so. We do not bill you until they ship.
If you have questions on any other sizes, feel free to ask or shoot me a PM. Thanks.
http://www.tirerack.com/tires/tires....affilliate=gf8
Sizes to be produced:
245/35R20
295/30R20
If you have questions on any other sizes, feel free to ask or shoot me a PM. Thanks.
http://www.tirerack.com/tires/tires....affilliate=gf8
Sizes to be produced:
245/35R20
295/30R20
08-17-2016, 04:12 AM
#42
I'm going to be running 265/35/19 and 285/35/19 RE71Rs at Thunderhill in a few weeks. I'm wondering if I can run 305/30/19 on the rear. Hmmmm
08-17-2016, 12:17 PM
#43
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08-17-2016, 11:16 PM
#44
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R20 sizes for GT4
I see Tirerack carries 255/40R20 and 285/35R20 for the RE-71Rs.
http://www.tirerack.com/tires/tires....re=835WR0RE71R
According to my calculations, the OEM tires have the following section heights (see http://www.tirerack.com/tires/tirete...jsp?techid=7):
front: 85.75mm
rear: 88.5mm
The tire sizes I indicated would have the following section heights:
front: 102mm
rear: 99.75mm
The difference between the OEM and the tires indicated is 0.44" in the front and 0.64" in the rear. This difference seems pretty minor to me.
Any thoughts?
http://www.tirerack.com/tires/tires....re=835WR0RE71R
According to my calculations, the OEM tires have the following section heights (see http://www.tirerack.com/tires/tirete...jsp?techid=7):
front: 85.75mm
rear: 88.5mm
The tire sizes I indicated would have the following section heights:
front: 102mm
rear: 99.75mm
The difference between the OEM and the tires indicated is 0.44" in the front and 0.64" in the rear. This difference seems pretty minor to me.
Any thoughts?
Last edited by webweaver; 08-17-2016 at 11:44 PM. Reason: Added calculations
08-18-2016, 12:06 PM
#45
Drifting
^ GT3 uses the same front tire width as the GT4 but gets a wheel that's half an inch wider. You'd be upsizing the tire by 10mm on a narrower wheel. The RE-71R in that size doesn't show a rim width range, but PSS in the same size shows our 8.5" width as the minimum. That plus the increased sidewall thickness makes me want to wait. The half-inch or so increase in overall size also seems fairly significant to me given this car's already low ride height from the factory.