I've been running that setup for over 2 years, and it's been fantastic. I also know that multiple other folks on the forum have as well, and confirmed the setup with my AMG tech as well as my tire guy.
@Gribouilly Even if you don't go 275 front (there's no reason not to), I highly recommend PS4S in 315 for the rears, especially if you are tuned or ever plan to go tuned, as any additional traction in the rear is needed.
thanks for you comments.
the front tires are really new, 2021 manufactured and less than 2.000kms I wont change them for now. (For memory : PZERO 265
but the rear are completely dry, the rubber is really hard and certainly could be dangerous on the wet street (in fact during the winter)
on my last SRT6 Crossfire, I used PS4S in front and rear and impressive tires ! Really good feeling with 👍🏻
i never do that but in propulsion car, certainly no problem : can I put Michelin PS4S for exemple at the rear and stay with Pirelli PZERO at the front ?
about the 305 or 315 (no big choice in 315 and relay more expensive) , what is the high to use ? Stay 30 size as 295 width ?
edit : the question is already made because PS4S doesnt in stock in 305
Basically you can assemble anything. Whether it is an improvement can only be seen in practical driving tests.
My personal opinion,
If avoidable, do not mix manufacturers. I already think that the tires are "matched" to each other.
Wouldn't go bigger than 305 with 11 "rims.
And yes take / 30. If the cross-section is / 25, the diameter will be too small.
This could lead to problems due to the increased wheel speed. Especially with the ESP / ABS.
The speedometer deviation also increases. /25 would be the right choice with 21 "rims.
At your place in the back 295/30 or 305/30 PZero. PZero are very good tires. However, I also prefer Michelin.
When all PZero are gone. Michelin PS4 or Cup 2 (depending on the focus)
Also note the load index. This is not just about real weight. Rather, it is about the load capacity at V-max.
Side notes / experiences:
In Germany you can't just change tires. The tires listed in the vehicle documents must strictly be fitted.
Another size must be approved by the vehicle manufacturer.
An alternative is an approval from the tire manufacturer. You won't get this, even from the same manufacturer, with different profile shapes.
In the case of big modifications, you still have the option of an individual approval by german "TÜV". Costs time, money and nerves. :-)
The load index must also, the limit or bigger, as in papers.
GTR has a load index of 106 at the rear. Thatīs 950kg per wheel or 1900kg on axle. That doesn't weigh the whole vehicle.
The maximum permissible axle load is 1075kg. Nevertheless, not even 105 is allowed without approval.
thanks for you comments.
the front tires are really new, 2021 manufactured and less than 2.000kms I wont change them for now. (For memory : PZERO 265
but the rear are completely dry, the rubber is really hard and certainly could be dangerous on the wet street (in fact during the winter)
on my last SRT6 Crossfire, I used PS4S in front and rear and impressive tires ! Really good feeling with 👍🏻
i never do that but in propulsion car, certainly no problem : can I put Michelin PS4S for exemple at the rear and stay with Pirelli PZERO at the front ?
about the 305 or 315 (no big choice in 315 and relay more expensive) , what is the high to use ? Stay 30 size as 295 width ?
edit : the question is already made because PS4S doesnt in stock in 305
I also agree about both load ratings and speed rating must handle the car's capabilities. We argue this all the time on other forums too. The Bentley forum is a good example where you have a heavy fast AWD car. Some really stretch the manufacturer's requirements in all directions - wheel/tire widths, staggered wheel diameters (on an AWD platform needing matching axle speeds on first gen models), load ratings too light, and combinations of all of the above.
On this platform we have a high performance track use car, even in the basic GT model. You can physically mount a tire that exceeds any one or combinations of - width, aspect ratio, diameters, load rates, but doing so degrades the car's performance capabilities. Simply with tires too wide that exceed wheel width, the sidewalls bulge and become distorted, so does the tread width, that will bulge and crown when inflated to track air pressures. These might not be evident by eye. A third issue is the way the bead meets and seals at the wheel rim. It too becomes distorted with tires too wide (or narrow).
I have only gone 305s in the rear which still fits within design specs, but I would never track the car that way. I only use these tires for cruising, CCs, etc. I don't even get aggressive on the street with these. To Stenzel's point, the UK also has strict rules and would reject a car in inspection with tires that do not strictly match the mfgr's requirements.
Here in the (outlaw) US we kinda do what we please. People make decisions all the time regarding modifications because they can, whether it is technically right or wrong. I know the arguments about "I and others have done it", "I have been running it this way for years with no problems", etc. and hear them on forums all the time. I accept those positions as you can only debate so far before some become angry and, in the end, it doesn't matter to me personally how some modify their cars. But, the differences become more important for the "first timers" who come on forums looking for reasoning on all sides. After that, it is up to you to take the risks with eyes wide open.
I also agree about both load ratings and speed rating must handle the car's capabilities. We argue this all the time on other forums too. The Bentley forum is a good example where you have a heavy fast AWD car. Some really stretch the manufacturer's requirements in all directions - wheel/tire widths, staggered wheel diameters (on an AWD platform needing matching axle speeds on first gen models), load ratings too light, and combinations of all of the above.
On this platform we have a high performance track use car, even in the basic GT model. You can physically mount a tire that exceeds any one or combinations of - width, aspect ratio, diameters, load rates, but doing so degrades the car's performance capabilities. Simply with tires too wide that exceed wheel width, the sidewalls bulge and become distorted, so does the tread width, that will bulge and crown when inflated to track air pressures. These might not be evident by eye. A third issue is the way the bead meets and seals at the wheel rim. It too becomes distorted with tires too wide (or narrow).
I have only gone 305s in the rear which still fits within design specs, but I would never track the car that way. I only use these tires for cruising, CCs, etc. I don't even get aggressive on the street with these. To Stenzel's point, the UK also has strict rules and would reject a car in inspection with tires that do not strictly match the mfgr's requirements.
Here in the (outlaw) US we kinda do what we please. People make decisions all the time regarding modifications because they can, whether it is technically right or wrong. I know the arguments about "I and others have done it", "I have been running it this way for years with no problems", etc. and hear them on forums all the time. I accept those positions as you can only debate so far before some become angry and, in the end, it doesn't matter to me personally how some modify their cars. But, the differences become more important for the "first timers" who come on forums looking for reasoning on all sides. After that, it is up to you to take the risks with eyes wide open.
FYI-using the Michelin Pilot Sport 4s as an example, 305/30-20 Michelin is ok with it performing and meeting its ratings on a rim width ranging from 10.5-11.5 and since the tread width is 11.2 their preferred spec (what THEY measure it on) is an 11 wide wheels. So go ahead and push that car hard on and off track with a 305 on a 11 wide GT/GTS factory rear wheel
So go ahead and push that car hard on and off track with a 305 on a 11 wide GT/GTS factory rear wheel
The specific 305 tire I have been talking about now in two different threads is not a performance tire. It was specifically purchased as a cruising tire that gets very good wear. I have two sets of rear tires. One set is for performance in a factory spec 295 and is meant to meet the factory design specs for maximum performance on this platform and I change into it for the track.
Since I drive my car a lot on the streets and attend a lot of events, CCs, etc., I wanted a tire I can beat around in while not wearing through a much more expensive track level tire. Since I save all of my "hotdogging" for the track, the cruising 305 looks good standing still, and works for my street driving, but I wouldn't dare push this 305 anywhere near a track.
The specific 305 tire I have been talking about now in two different threads is not a performance tire. It was specifically purchased as a cruising tire that gets very good wear. I have two sets of rear tires. One set is for performance in a factory spec 295 and is meant to meet the factory design specs for maximum performance on this platform and I change into it for the track.
Since I drive my car a lot on the streets and attend a lot of events, CCs, etc., I wanted a tire I can beat around in while not wearing through a much more expensive track level tire. Since I save all of my "hotdogging" for the track, the cruising 305 looks good standing still, and works for my street driving, but I wouldn't dare push this 305 anywhere near a track.
Widen up those performance ones too, more lateral and straight line grip!
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