anyone running a 325/30/19 rear (997tt)
#1
anyone running a 325/30/19 rear (997tt)
if so, what are you running up front ?
to everyone else with 19" wheels , what size rear tire are you running (besides the stock 305/30/19) ?
WOULD A 325/30/19 work with a 245/35/19 (michelin pilot sport cup) on a 997tt ?
to everyone else with 19" wheels , what size rear tire are you running (besides the stock 305/30/19) ?
WOULD A 325/30/19 work with a 245/35/19 (michelin pilot sport cup) on a 997tt ?
Last edited by DNugget991GT3; 03-01-2012 at 01:06 PM.
#2
I think you will find more information if you search for "325/30-19". I remember lots of people thinking about running 325's in the rear but I do not remember anyone actually doing it. Last time I looked, there was not a good front size to match the 325's. Anything wider than 245 in the fronts can rub. Make sure you keep the front/rear diameters very close to stock.
#4
I do not think it would be a good choice because it is 4.6% larger than stock. There are two important factors when changing the tire sizes on the 997TT: 1) the difference in size (circumference), and 2) the front/rear ratio; you need to keep both pretty close to stock.
The stock rear tires (305/30-19) are 2.9% larger than the stock fronts (235/35-19). A while back, the consensus was that the sizes (circumferences) should be within +/- 3% of stock and the front/rear ratio should be within 1% of stock, keeping in mind that the stock ratio is not 1:1. It makes it pretty tricky to change the tire sizes.
The stock rear tires (305/30-19) are 2.9% larger than the stock fronts (235/35-19). A while back, the consensus was that the sizes (circumferences) should be within +/- 3% of stock and the front/rear ratio should be within 1% of stock, keeping in mind that the stock ratio is not 1:1. It makes it pretty tricky to change the tire sizes.
#5
I do not think it would be a good choice because it is 4.6% larger than stock. There are two important factors when changing the tire sizes on the 997TT: 1) the difference in size (circumference), and 2) the front/rear ratio; you need to keep both pretty close to stock.
The stock rear tires (305/30-19) are 2.9% larger than the stock fronts (235/35-19). A while back, the consensus was that the sizes (circumferences) should be within +/- 3% of stock and the front/rear ratio should be within 1% of stock, keeping in mind that the stock ratio is not 1:1. It makes it pretty tricky to change the tire sizes.
The stock rear tires (305/30-19) are 2.9% larger than the stock fronts (235/35-19). A while back, the consensus was that the sizes (circumferences) should be within +/- 3% of stock and the front/rear ratio should be within 1% of stock, keeping in mind that the stock ratio is not 1:1. It makes it pretty tricky to change the tire sizes.
#7
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#8
I'm pretty sure this discussion is only about 19" tires. But you are correct, those fitments in 20" are fine.
#9
Yeah - OP was asking about 19's. OEM 305/30-19 and 235/35-19 have a diameter difference of 2.8% (OK). 325/25-20 and 235/30-20 have a diameter difference of 3.2% (on the high end of acceptable) and the OP's setup of 325/30-19 matched with a 245/35-19 would have a diameter difference of 3.5% (again on the high end - I'd be worried).
#11
If you have time, this is an old post. I realize the sizes are different but it's good information. Seems to be consensus that 3% or less difference is OK.
https://www.6speedonline.com/forums/...15s-rears.html
https://www.6speedonline.com/forums/...15s-rears.html
#13
I just wanted to add another bit of information. My summer front/rear ratio is 0.97 ratio and my winter front/rear ratio is 0.98. The car is set-up to tolerate a little larger (3%) circumference tire in the rear. It also does fine with the Porsche recommended winter tires, which are 2% larger in the rear.
I just don't think you are going to find an acceptable combination using 325's on 19's.
Summer: 305/30-19 and 235/35-19
Winter: 295/30-19 and 235/35-19
I just don't think you are going to find an acceptable combination using 325's on 19's.
Summer: 305/30-19 and 235/35-19
Winter: 295/30-19 and 235/35-19
#15
305/30/19's are stock sizes so they better work perfectly fine.