rear tire size - 305 or 325?
#1
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2016 AMG GTS Edition 1, 2011 Audi R8 5.2, 2003 BMW M5, 1978 Alfa Romeo Spider, 1995 RUF BTR-2
rear tire size - 305 or 325?
Hey Team,
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
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
#2
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Welcome to the forum.
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.
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.
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Andrew Poole (09-28-2016)
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2016 AMG GTS Edition 1, 2011 Audi R8 5.2, 2003 BMW M5, 1978 Alfa Romeo Spider, 1995 RUF BTR-2
Thanks!
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.
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; 09-28-2016 at 04:28 PM.
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I have made the calculation and I am planning to go with 325/30/20 and I hope this higher ratio counter my need to lower the vehicle but I need to confirm with my wheel guy.
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.
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.
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2016 AMG GTS Edition 1, 2011 Audi R8 5.2, 2003 BMW M5, 1978 Alfa Romeo Spider, 1995 RUF BTR-2
I decided to go with WB's recommendation for a 12.5'' wheel coupled with the 325/25/20. I personally wouldn't go with a taller tire simply to fill wheel gap, but thats a personal preference.
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.
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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2020 Audi R8 V10, 2016 AMG GTS, 2018 E63S Edition 1, 2018 Porsche GTS Cab, 2012 C63 BS
The 325x25x21 is the proper "plus size" set up to keep the rolling diameter within oem spec.
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More dilemma on this subject and hope someone can chime in.
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.
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.
#9
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Id say you are into 25 and not 30, the dia is way too much unless you have proven cars to varify the fitment
and 11.5 would get 325 and 12 would get 325 minimum , no reason to get 12 unless youre getting wider tire
and 11.5 would get 325 and 12 would get 325 minimum , no reason to get 12 unless youre getting wider tire
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Wheel Boutique already has built wheels with 12.5 in back with no fitment issues and yes, my plan is to get wider tires in back.
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?
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?
#12
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F/R Handling balance will be affected. If you're not tracking the car, it won't matter; if you do, it matters a lot.
#13
Crappy picture, but this is my car sitting on HRE 300Ms that are as follows
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.
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.
#14
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here's a shot of my 21x11.5 on MPSS 305/25 lowered to the max drop on KW HAS. there's a bit of rubbing when hitting large dips but nothing i'm too concerned about.