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It just seems silly for them to use the Dunlop/Goodyear/Bridgestone/Pirelli tires for those who order the X73 Sport Suspension.
 

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I agree. I'm running 245/35-20 and 285/30-20 MPSS tires on my X73 981CS and it's one of the easiest performance mod's you can do.
 
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I had Michelins on my previous car (BMW M3) and was very satisfied. Have the Pirellis on the CGTS but only ~200 miles on the car. So, too early for me to do any kind of comparison. I'd have been much happier if it had come with Michelins!
 

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Oddly enough I actually don't like Michelin tires that much ... sidewalls are too soft
 

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It just seems silly for them to use the Dunlop/Goodyear/Bridgestone/Pirelli tires for those who order the X73 Sport Suspension.
Chances are, they do this because most people wont want to replace their tires after 8000 miles
 

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I agree. I'm running 245/35-20 and 285/30-20 MPSS tires on my X73 981CS and it's one of the easiest performance mod's you can do.
Does the difference in overall tire height cause issues with the speedometer or traction control at all?

BTW, the MPSS tires are awesome. I've run them on my S2000 and they were just fantastic all around.
 

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It will have an effect on the ABS, as the individual wheel speeds are based on a certain tire circumference and when you add taller tires that appear to be going faster, the ABS says "oh, i need less brake pressure becuase that rear tire is going faster than the front tire." In theory, a taller rear tire will have an effect of less rear brake bias. The new 981s have so much fender room and quarter panel room that you can accommodate much wider tires than you were able to wit the 987. As a rule of thumb, I tell everyone to do the math on their factory tire circumferences and pick the profiles based on those dimensions. The OE 19s @ 235/40/19FR and 265/40/19R are 82.9" and 85.8" tall respectively; the 20s @ 235/35/20FR & 265/35/20R are 83.18" and 85.8" tall respectively. You need to keep these dimensions the same and then you can pick and choose whatever widths you want. Just be careful that if you go wider than OE in the FR or R you need to space the wheel further out to get away from the strut suspension. Cheers!
 

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I belive John at BGB meant "rolling circumference" versus "height" in his numbers above.
 

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The 285/30-20 rear tire is lower in height than the stock 265/35-20 and lowers the rear by ~0.4". The 245/35-20 front tire is taller than the stock 235/35-20 and raises the front by ~0.2". The X73 suspension drops my '14 CS by 20mm (0.8"), so this tire combination has the affect of reducing the rake from front to back of the car. The tire diameters sizes are still within the Porsche stock tire ranges.

I've driven this combination at 3 track events and had no ABS issues. With a proper track alignment and these tires, I was very impressed with the grip.
 
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