rear tire size - 305 or 325?
I'm deciding on a +1 HRE wheel/tire package from WheelsBoutique (20''F/21''R). The options for the REAR are:
11.5'' wheel with a 305mm Michelin PSS,
or a 12'' wheel with 325mm Pirelli P Zero
Apparently the PSS is not available in the wider fitment.
Any advice / opinions on tire choice? Do I risk rubbing with a 325 with the car lowered on RennTech springs?
thanks!
Andrew
According to tire rack 325/30/21 are available in PSS Michelin.
What wheels are you going with? I understand you want an aggressive setup but 12s at 21" seem extreme. I would stay at 11.5 305s and you won't be bucking around on the street lol.
You may be right on the 11.5 / 305 recommendation, although I have 325's on my R8 and its quite civil...and this car makes more power.
Wouldn't a 30 series tire be too big? WB is recommending a 25series whether I go 305 or 325... I need to do some rolling radius calculations to figure this out...


Oh, and looking at an HRE RS103M in satin bronze.
Last edited by Andrew Poole; Sep 28, 2016 at 04:28 PM.
Since you already have your car lowered, I am skeptical with being able to go that tall. I would trust WB as this is not their first rodeo.
Can you comment on the difference in ride versus stock with our RT springs.
Ride comfort is unaffected by the Renntech springs to my senses, I notice no difference in ride quality and you have height adjustability to boot. Highly recommended.
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The consensus this so far has been the 325/25 for the back tire.
When you calculate overall height in back, the 325/25/20 is 26.4 inches and the 325/25/21 is 27.4 inches. Stock height is 27 inches on 20s and 27.1 on 19s.
The GT-R is coming with 325/30/20 which is a 27.7 height. Front is 275/35/20 which is 27.6 height so height is same front and rear. interestingly enough, the GT and GTs have a height difference of 1 inch from front to rear (26 versus 27).
Q1: does anyone see an issue of going 325/30/20 in back of a GT?
Q2: does anyone see an issue with going 335/30/20 in back of GT? 27.9 height versus 27.7 (assuming wheel manufacturer can make it fit width wise). reason I am asking is because I can get a PSS versus a PSC2 in 335.
Q3: if you go with 325/30/20 or 335/30/20 in rear, would you then go with 265/35/20 (height of 27.3) in front to be closer in height to the back (27.9)?
As a side note, my car is a daily driver and I do not want to lower it and worry about scraping and damaging the front aero package. Choosing the taller tire that is on GTR would raise my car less than 1/2 inch and that's even a bonus in my book.
Thanks in advance guys.
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and 11.5 would get 325 and 12 would get 325 minimum , no reason to get 12 unless youre getting wider tire
The 30 and 35 tires are what the GT-R comes with so MB has already proven there is no height fitment issues.
Am I missing something?
Rear: 21x12.5, P-zero 325/25/21
Front: 20x9.5, P-zero 265/30/20
I have never had issues with rubbing, but my car sits at stock height. I think there is a little room to go down, but I drive this car in the real world and don't want to risk being too low.







