[PLF69]

Originally Posted by Mospeada

i use cup2 on my car and recently got 265/35 cup2 and saw that they have new DT1 (different tread 1) and tire rating of 240!!! that's crazy. and it's bmw star. i looked everywhere and found that 245/35 is also DT1 240 rating. so that's whats going to be on M2 wheels . i do not see 285/35 or 285/30 offered in DT1 yet. maybe they will. then i saw this vid and one of the large ass tire has to be 285 rear on this new M car. so that tells me 285 DT1 star rated tire is coming. i think it's awesome that cup2 is getting upgraded . i'm a big fan of cup2 and was going to switch to S007A, i prolly will anyway becuase of cost difference and so many tires i go through each year

Your not going to be happy, I ran R888R after cup2's and I hated them with a passion. It's like continental OEM vs PS4S difference. S007 are in the same category, there is a reason for the price.

[SYT_Shadow]

R888R are the only tires I've thrown away at half tread. I don't know what those tires serve for but at the track they were much slower than RE71s, loud as hell, bad in water... i guess they have a use somewhere but wow

[solstice]

Originally Posted by solstice

You do know that BMW’s 3 series
platforms have offered AWD since the E30, right?

Not sure what you’re trying to say here but the introduction of AWD in the G8X is not the reason to the shift in weight distribution. The 3/4 series platform that the M cars are based upon shifted the balance and the M cars inherits the change.

Looking at the G20/22 specifications it’s interesting to see that I6 move the scale 1% forward vs the I4 and Xdrive shift it another percent.

[CanAutM3]

Originally Posted by Mospeada

i use cup2 on my car and recently got 265/35 cup2 and saw that they have new DT1 (different tread 1) and tire rating of 240!!! that's crazy. and it's bmw star. i looked everywhere and found that 245/35 is also DT1 240 rating. so that's whats going to be on M2 wheels . i do not see 285/35 or 285/30 offered in DT1 yet. maybe they will. then i saw this vid and one of the large ass tire has to be 285 rear on this new M car. so that tells me 285 DT1 star rated tire is coming. i think it's awesome that cup2 is getting upgraded . i'm a big fan of cup2 and was going to switch to S007A, i prolly will anyway becuase of cost difference and so many tires i go through each year

Be wary, that 265/35R19 PSC2 you mention is the REAR tire for the M2cs and SHOULD NOT be used on the front axle of the M3/4.

For some reason BMW chose the imprecise star designation for all their specific tires. Other manufacturers choose to use a combination of numbers and letters which makes it clearer what specific vehicle application the tires were designed for.

[KoenG]

Originally Posted by NISFAN

This leads to bean counters fighting back undoing all the expensive stuff you implemented to achieve "the BMW balance", because it's broken anyway and Audi do OK without. You've lost the anchor in the argument, that historical yardstick. It doesn't get replaced by 55:45, no it it just goes.

Indeed, but the 50/50 is a design objective, not something that you discover afterwards.

The trick they use since ever, is pushing the engine as much as possible to the center of the car and moving some periferals like the battery to the back. With their longitudinal RWD driveline architecture they can also push the transmisson to the center of the car while a transversal config has it installed at the same position as the engine. Of course, you would like to concentrate the weight as much as possible between the axles, but you still need some interior space.

Nonetheless, why would they destress this USP now? Is it that customers more value the 0.4 inch of added interior length?

[solstice]

Originally Posted by KoenG

Indeed, but the 50/50 is a design objective, not something that you discover afterwards.

The trick they use since ever, is pushing the engine as much as possible to the center of the car and moving some periferals like the battery to the back. With their longitudinal RWD driveline architecture they can also push the transmisson to the center of the car while a transversal config has it installed at the same position as the engine. Of course, you would like to concentrate the weight as much as possible between the axles, but you still need some interior space.

Nonetheless, why would they destress this USP now? Is it that customers more value the 0.4 inch of added interior length?

It would be interesting to know why the 3 series got the shift in balance. Maybe something to do with chassis sharing with EV - i4, mild hybrid design or as you say extra cabin space.

[Boss330]

Originally Posted by NISFAN

BMW has for a long time aimed to achieve the nirvana of a 50:50 balance. I know you have been vocal about the 50:50 not evidenced at being the best, and I'd certainly agree it isn't the best balance for a car, mid engined sports cars have proven this. But on practical terms for an FR chassis (front engined, rear drive for those that are unfamiliar with the FR term), 50:50 is about as good as you can practically achieve. Even so it's not easy achieve, that's why Mercedes and others don't even bother. It costs BMW lots of money in weight engineering the crap out an FR to achieve this long standing benchmark and BMW tradition. This point is important.

In adding an AWD drivetrain we have introduced drive train drag and added weight to the front axle. Both of these increase under steer. How do we counter under steer? Increasing front axle grip. Viola, bigger section front tyres. You got it more front weight, and since you've increased the effectiveness of the front axle, the bigger brakes need to go here, more chassis rigidity here too, there are new forces on the front axles that we didn't have before. Incrementally the weight balance moves further and further forward and there is nothing you can do about it other than to embrace the fact that 50:50 is dead.

This leads to bean counters fighting back undoing all the expensive stuff you implemented to achieve "the BMW balance", because it's broken anyway and Audi do OK without. You've lost the anchor in the argument, that historical yardstick. It doesn't get replaced by 55:45, no it it just goes.

Oh and if you think that's OK, the RWD version will still be OK? Right? No, the whole platform has been compromised. Strut turrets, front geometry aimed to driven front axle inclinations. Wheel wells designed for wide (unnecessary) tyres, carrying big heavy brakes. Chassis strength focussed to adapt to AWD needs, the list goes on, but all at cross purpose to 50:50 balance. This is a real shift, the G20 340i is AWD only in many markets, this indicates the direction of chassis development for AWD. It ends in a video showing distorted weight difference between old and new and not a peep about weight distribution. Purposely omitted no doubt.

Coming back to your question, it is inevitable. There are only two manufacturers that I can recall having tried to control weight distribution on FAWD platforms. Subaru and Nissan GTR. One is a low volume super car with an expensive and unpractical transaxle gearbox, the other no longer bothers. A lost battle.

C'est la vie.

Lets put the f/r weight distribution in context with the F82:

The G82 M4 Coupe has 52,7/47,3
The G82 M4 Comp has 53,1/46,9 (auto trans)

The F82 M4 std had 52,8/47,2
The F82 M4 GTS had 52,9/47,1

Yes, the G8x carries more weight on the front axle due to higher curb weight (although not as much heavier than the F82 if optioned right).

But the weight distribution is pretty similar to the F82...

By comparison the Audi RS4/5, which suffers from "Audisteer", weighs 1805/1740kg and has a 56,3/43,7 (RS4) and 58,2/41,8 (RS5) weight distribution.

To put that in perspective:

The RS5 weighs 1013kg on the front axle
The M4 manual weighs 916kg on the front axle, or in the case of the "lightweight" version from the first video, 882kg
The M4 Comp weighs 935kg on the front axle

The F82 weights are taken from Sport Auto Supertests and are based on tested weights. The G82 weights are taken from the tech sheets from BMW posted on Bimmerpost.

[KoenG]

Originally Posted by Boss330

Lets put the f/r weight distribution in context with the F82:

The G82 M4 Coupe has 52,7/47,3
The G82 M4 Comp has 53,1/46,9 (auto trans)

The F82 M4 std had 52,8/47,2
The F82 M4 GTS had 52,9/47,1

Yes, the G8x carries more weight on the front axle due to higher curb weight (although not as much heavier than the F82 if optioned right).

But the weight distribution is pretty similar to the F82...

By comparison the Audi RS4/5, which suffers from "Audisteer", weighs 1805/1740kg and has a 56,3/43,7 (RS4) and 58,2/41,8 (RS5) weight distribution.

To put that in perspective:

The RS5 weighs 1013kg on the front axle
The M4 manual weighs 916kg on the front axle, or in the case of the "lightweight" version from the first video, 882kg
The M4 Comp weighs 935kg on the front axle

The F82 weights are taken from Sport Auto Supertests and are based on tested weights. The G82 weights are taken from the tech sheets from BMW posted on Bimmerpost.

So, actually, there is no substantial shift in balance between F and G then?

[CanAutM3]

Originally Posted by KoenG

So, actually, there is no substantial shift in balance between F and G then?

There is one. Boss330 numbers are a bit misleading they way they are presented. Showing the two extreme apples-to-apples comparisons:

F82 6MT -> G82 6MT RWD
52.1/47.9 -> 52.7/47.3 2

F80 DCT -> G80 8AT RWD
52.2/47.8 -> 53.1/46.9

The shift is in 0.6% to 0.9% range depending on model and transmission. And I am even using the AM&S data for the F82 6MT, as the BMW official press release numbers were much better at 51.8/48.2. While not drastic, it is a progressive shift we have been seeing with every generation with more and more weight on the front axle. Expect the AWD version to make it even worse.

Now if you do the math to figure if it is meaningful or not: the 6MT, the G8X carries 117lb of its extra 181lb (65% of it) on the front wheels.

[solstice]

Originally Posted by Boss330

Lets put the f/r weight distribution in context with the F82:

The G82 M4 Coupe has 52,7/47,3
The G82 M4 Comp has 53,1/46,9 (auto trans)

The F82 M4 std had 52,8/47,2
The F82 M4 GTS had 52,9/47,1

Yes, the G8x carries more weight on the front axle due to higher curb weight (although not as much heavier than the F82 if optioned right).

But the weight distribution is pretty similar to the F82...

By comparison the Audi RS4/5, which suffers from "Audisteer", weighs 1805/1740kg and has a 56,3/43,7 (RS4) and 58,2/41,8 (RS5) weight distribution.

To put that in perspective:

The RS5 weighs 1013kg on the front axle
The M4 manual weighs 916kg on the front axle, or in the case of the "lightweight" version from the first video, 882kg
The M4 Comp weighs 935kg on the front axle

The F82 weights are taken from Sport Auto Supertests and are based on tested weights. The G82 weights are taken from the tech sheets from BMW posted on Bimmerpost.

Very interesting. Thanks for digging up that F82 data. Insignificant change in weight distribution indeed.

[CanAutM3]

Originally Posted by solstice

Very interesting. Thanks for digging up that F82 data. Insignificant change in weight distribution indeed.

See post above. It's all how it is presented and interpreted...

The F8X are easy to dog out, look for yourself: https://f80.bimmerpost.com/forums/sh...d.php?t=923444

[KoenG]

Originally Posted by CanAutM3

There is one. Boss330 numbers are a bit misleading they way they are presented.

F82 6MT -> G82 6MT RWD
52.1/47.9 -> 52.7/47.3

F80 DCT -> G80 8AT RWD
52.2/47.8 -> 53.1/46.9

The shift is in 0.6% to 0.9% range depending on model and transmission. While not drastic, it is a progressive shift we have been seeing with every generation with more and more weight on the front axle. Expect the AWD version to make it even worse.

Tx, but it makes it even more "strange" that they didn't try (or did they?) to have it more rear biased? I have to admit, I can't comprehend this G8x car from so many aspects!!

The F8x, I fell in love with for all the right reasons, but this G8x thing is really hard to understand since it seems to provoke all known virtues of the M brand we knew. Grrrr...

These moronic video clips aren't really helping, it's all about the bells and whistles, like tires and seats, and NOTHING about the core.

[solstice]

Originally Posted by CanAutM3

See post above. It's all how it is presented and interpreted...

The F8X are easy to dog out, look for yourself: https://f80.bimmerpost.com/forums/sh...d.php?t=923444

Thanks, looks like a known reference to the handling impact between the F8X and G8X weight balance should be rather similar to the behavior of an MT and DCT F8X. Can’t say I felt any significant difference in handling when I drove an F82 DCT on track vs my MT. It for sure didn’t plow like an Audi

[PLF69]

Originally Posted by CanAutM3

the G8X carries 117lb of its extra 181lb (65% of it) on the front wheels.

Not to bad if you compare the difference between de OG M2 and M2 Comp, if I recall the over 100lbs is mostly on the front and the only change to the structure was adding a part they already have. (M3/4 front alum/carbon brace)

A lot more work went on the G80 to make sure everything is balanced out, well I hope so..

[solstice]

Originally Posted by PLF69

Not to bad if you compare the difference between de OG M2 and M2 Comp, if I recall the over 100lbs is mostly on the front and the only change to the structure was adding a part they already have. (M3/4 front alum/carbon brace)

A lot more work went on the G80 to make sure everything is balanced out, well I hope so..

Count on it, the staggered tires and wider front tires should both help narrow the impact and maybe even reversing it if reviews and BMW’s own comments are to be believed. They are proud of the G8X front axle

[solstice]

The G20 press release have a lot of information on chassis improvements over the F30. Its worth reading to understand that the G8X do not only inherit a heavier, larger platform. There’s a lot of good stuff in there as well.

https://www.bimmerpost.com/goodiesfo...w-3-series.pdf

[bm323]

Originally Posted by Boss330

Lets put the f/r weight distribution in context with the F82:

The G82 M4 Coupe has 52,7/47,3
The G82 M4 Comp has 53,1/46,9 (auto trans)

The F82 M4 std had 52,8/47,2
The F82 M4 GTS had 52,9/47,1

Is the F92 M4 std in your example above with the manual or the DCT?

Do you have any comment on the reason for the skidpad difference between the M340i RWD (0.96g) vs the M440i xDrive (0.91g) with both having the same PS4S specs despite the M440i xDrive having a “sportier” built (lower and wider track)?

https://www.caranddriver.com/reviews...y-maintenance/

https://www.caranddriver.com/reviews...y-the-numbers/ "Even with 19-inch Michelin Pilot Sport 4S summer tires (18s with all-seasons are standard), it managed only 0.91 g of skidpad grip, and understeer dominates."

[solstice]

Originally Posted by bm323

Is the F92 M4 std in your example above with the manual or the DCT?

Do you have any comment on the reason for the skidpad difference between the M340i RWD (0.96g) vs the M440i xDrive (0.91g) with both having the same PS4S specs despite the M440i xDrive having a “sportier” built (lower and wider track)?

https://www.caranddriver.com/reviews...y-maintenance/

https://www.caranddriver.com/reviews...y-the-numbers/ "Even with 19-inch Michelin Pilot Sport 4S summer tires (18s with all-seasons are standard), it managed only 0.91 g of skidpad grip, and understeer dominates."

You have one review for RWD M340i and the other for AWD M440i as one factor.
Another is that the M440i is a mild hybrid with extra weight.

The rest could possibly be test environment differences, temperature, state and wear of tires etc. I wouldn’t be too concerned about it as a general 3 vs 4 apples to apples specification characteristic.

[bm323]

Originally Posted by solstice

You have one review for RWD and the other for AWD as one factor.
Another is that the M440i is a mild hybrid with extra weight.

Yes, difference of 159 lbs with more weight at the front of M440i xDrive; worse skidpad reading despite it being "sportier" built.

[solstice]

Originally Posted by bm323

Yes, difference of 159 lbs with more weight at the front of M440i xDrive; worse skidpad reading despite it being "sportier" built.

A same day, apples to apples 3 vs 4 specification cars I wouldn’t be surprised if the 4 edges out the 3.

[bm323]

Originally Posted by solstice

The G20 press release have a lot of information on chassis improvements over the F30. Its worth reading to understand that the G8X do not only inherit a heavier, larger platform. There’s a lot of good stuff in there as well.

https://www.bimmerpost.com/goodiesfo...w-3-series.pdf

Can’t rely mainly on the pom pom cheers. BMW claimed the 8 series was a game changer sport car before release; look at where it is.

Edit: I was taken in with the "pom poms" and posted on this.

[solstice]

Originally Posted by bm323

Can’t rely mainly on the pom pom cheers. BMW claimed the 8 series was a game changer sport car before release; look at where it is.

Edit: I was taken in with the "pom poms" and posted on this.

Absolutely agree, you need to filter out the Pom poms and focus on the objective changes/improvements.