[Intricate39]

Hello forum members!

Question that I can’t seem to get a conclusive answer on.

My 2021 M340i RWD came with the 792m Square A/S package, and I can’t wait to get rid of them.

I’m pretty settled on getting a nice aftermarket lightweight staggered setup. Leaning towards the G025 by Rays.

Does anyone know if the M340i can fit M3 sized wheels/tires?

I’d like to go with what’s on M3, but I don’t want any rubbing, or issues with the speedo. Something like this:

Fronts: 9x19 ET:29 on 265/35ZR19 98Y XL
Rears: 10x20 ET:40 on 285/30ZR20 99Y XL

Thanks in advance for the knowledge!

[rostrata]

Originally Posted by Intricate39

Hello forum members!

Question that I can’t seem to get a conclusive answer on.

My 2021 M340i RWD came with the 792m Square A/S package, and I can’t wait to get rid of them.

I’m pretty settled on getting a nice aftermarket lightweight staggered setup. Leaning towards the G025 by Rays.

Does anyone know if the M340i can fit M3 sized wheels/tires?

I’d like to go with what’s on M3, but I don’t want any rubbing, or issues with the speedo. Something like this:

Fronts: 9x19 ET:29 on 265/35ZR19 98Y XL
Rears: 10x20 ET:40 on 285/30ZR20 99Y XL

Thanks in advance for the knowledge!

Offsets are pretty close to stock 19” staggered setup. At least those wheel sizes are truly staggered. It also looks like the tire sizes you’ve shown above indicate a +1.5% diameter difference. I’m not sure if the RWD setup will care about that as much as an AWD setup would. 1.5% is likely okay but there’s no way to know if there’s any special DSC coding for the M3/4 that would negate any drivetrain errors.

Bottom line: best to talk to your dealer. I don’t see any real issues but that’s a sizable investment to make on a guess. Good luck!

[Intricate39]

Originally Posted by rostrata

Offsets are pretty close to stock 19” staggered setup. At least those wheel sizes are truly staggered. It also looks like the tire sizes you’ve shown above indicate a +1.5% diameter difference. I’m not sure if the RWD setup will care about that as much as an AWD setup would. 1.5% is likely okay but there’s no way to know if there’s any special DSC coding for the M3/4 that would negate any drivetrain errors.

Bottom line: best to talk to your dealer. I don’t see any real issues but that’s a sizable investment to make on a guess. Good luck!

Hmmm. The dealer has less info than the layman here. They told me my current wheels were staggered…

Any info on what the largest wheel and tire setup that works well with the m340 is?

[rostrata]

Originally Posted by Intricate39

Hmmm. The dealer has less info than the layman here. They told me my current wheels were staggered…

Any info on what the largest wheel and tire setup that works well with the m340 is?

Oh shit. I wrote that kinda crappy. So your current wheels in the 19” setup are, technically speaking, staggered. Different width in the rear than front. However, the sizes you mentioned in your OP, 19” diameter front to 20” diameter rear, is “truly” staggered. My opinion mixed with some technicalities so yeah, that was my bad. Anywho.. went back and looked. The offsets are the same between the M3/4 wheels and out stock wheels. I doubt you’ll experience any issues. If you are considering an aftermarket BBK, like an AP Racing kit or something larger, then you would definitely need to visit a dealer that has an M3/4 with the wheels you are considering so you can ensure the spokes would clear the calipers. I’m sure they would. After all, I believe the stock M3/4 brakes are quite a bit bigger than stock brakes on the M340.

[Intricate39]

Originally Posted by rostrata

Oh shit. I wrote that kinda crappy. So your current wheels in the 19” setup are, technically speaking, staggered. Different width in the rear than front. However, the sizes you mentioned in your OP, 19” diameter front to 20” diameter rear, is “truly” staggered. My opinion mixed with some technicalities so yeah, that was my bad. Anywho.. went back and looked. The offsets are the same between the M3/4 wheels and out stock wheels. I doubt you’ll experience any issues. If you are considering an aftermarket BBK, like an AP Racing kit or something larger, then you would definitely need to visit a dealer that has an M3/4 with the wheels you are considering so you can ensure the spokes would clear the calipers. I’m sure they would. After all, I believe the stock M3/4 brakes are quite a bit bigger than stock brakes on the M340.

I was trying to say that the dealer doesn’t know what their talking about .

When an M340i comes with All seasons, they don’t actually stagger them. The wheels/tires I have are the 792M. The tires are all 225, and I measured the wheels, they are all 8” wide. Hence the desire to get some wider wheels/tires. Especially once I start adding power.

I guess what I’m really trying to figure out is if an M3/4 can fit the listed wheels in the original post wouldn’t it make sense that the m340’s can?

Unless there has been some “M” modification to the chassis on the full M cars to allow for wider wheels/tires.

What I was trying to do is emulate this setup for the M3/4’s with the G025’ and PS4S.I have the stock M performance brakes. So that shouldn’t be an issue.

https://www.getbmwparts.com/oem-part...b3J5IFBhZ2U%3D

Thanks for all the help so far! Maybe I can be a test case!

[djaycemaster]

my car came with 20 inch wheels with 225/35/r20 in the front and 255/30/r20 in the back.

[rostrata]

Originally Posted by Intricate39

I was trying to say that the dealer doesn’t know what their talking about .

When an M340i comes with All seasons, they don’t actually stagger them. The wheels/tires I have are the 792M. The tires are all 225, and I measured the wheels, they are all 8” wide. Hence the desire to get some wider wheels/tires. Especially once I start adding power.

I guess what I’m really trying to figure out is if an M3/4 can fit the listed wheels in the original post wouldn’t it make sense that the m340’s can?

Unless there has been some “M” modification to the chassis on the full M cars to allow for wider wheels/tires.

What I was trying to do is emulate this setup for the M3/4’s with the G025’ and PS4S.I have the stock M performance brakes. So that shouldn’t be an issue.

https://www.getbmwparts.com/oem-part...b3J5IFBhZ2U%3D

Thanks for all the help so far! Maybe I can be a test case!

Ah! Now I’m getting the picture. I’ve been in contact with other wheel manufacturers about a truly staggered fitment in sizes close to what you mentioned. The only issue is going wider than 10”. I think you could fit a 10.5” width but 11” I’m told is a no-go. I really can’t see why you wouldn’t be able to do a direct swap. Just keep in mind that with a 10” wide wheel with the same offsets, you gain and inch on each side. For us with staggered rear tires at 8.5” width, we would gain approximately 45mm in total width for a 10” wide tire. That equates to 22.5mm on each side. Most folks with spacers won’t go beyond 15mm which still pokes out a touch. So really what that means is, with a flush fitment, you’d want to keep it at 9.5” width, tops, at the same offsets. Unfortunately, I don’t believe there’s an option for that. But! In the price range that you would be at to get those wheels, you would be better off just going a custom route and having wheels made specifically for the offsets you want. Unless of course you are okay with them poking out. Because the M3/4 are essentially wide-body designs so that’s why they fit perfectly for them, but not for us.

You could easily get a comparable looking set of custom flow-formed or forged wheels for the money you’ll spend on the BMW wheels, even used. And they’ll fit better.

Anyway. Hope that helps answer your questions a bit better. Down to continue chatting if you have any other ideas you want to throw out.

[Intricate39]

Originally Posted by rostrata

Ah! Now I’m getting the picture. I’ve been in contact with other wheel manufacturers about a truly staggered fitment in sizes close to what you mentioned. The only issue is going wider than 10”. I think you could fit a 10.5” width but 11” I’m told is a no-go. I really can’t see why you wouldn’t be able to do a direct swap. Just keep in mind that with a 10” wide wheel with the same offsets, you gain and inch on each side. For us with staggered rear tires at 8.5” width, we would gain approximately 45mm in total width for a 10” wide tire. That equates to 22.5mm on each side. Most folks with spacers won’t go beyond 15mm which still pokes out a touch. So really what that means is, with a flush fitment, you’d want to keep it at 9.5” width, tops, at the same offsets. Unfortunately, I don’t believe there’s an option for that. But! In the price range that you would be at to get those wheels, you would be better off just going a custom route and having wheels made specifically for the offsets you want. Unless of course you are okay with them poking out. Because the M3/4 are essentially wide-body designs so that’s why they fit perfectly for them, but not for us.

You could easily get a comparable looking set of custom flow-formed or forged wheels for the money you’ll spend on the BMW wheels, even used. And they’ll fit better.

Anyway. Hope that helps answer your questions a bit better. Down to continue chatting if you have any other ideas you want to throw out.

Rostrata, thank you for all the info. The M3 being a “wide body” makes all the sense as to how it fits the larger wheels. Since I’m a wheel noob, would the following work without protruding:

19x8.5 Front Inset: 36
19x9.5 Rears Inset: 44

Would have no idea the tire size from there but if those wheels would work that would be a start.

Located here:

https://www.rayswheels.co.jp/product...=en&wheel=G025

[rostrata]

Originally Posted by Intricate39

Rostrata, thank you for all the info. The M3 being a “wide body” makes all the sense as to how it fits the larger wheels. Since I’m a wheel noob, would the following work without protruding:

19x8.5 Front Inset: 36
19x9.5 Rears Inset: 44

Would have no idea the tire size from there but if those wheels would work that would be a start.

Located here:

https://www.rayswheels.co.jp/product...=en&wheel=G025

Love some good Ray's. Very nice pick. So I went an did a little quick math with more accurate numbers rather than the shit I was pulling out of the air earlier. Here's what I've come up with:

OEM FRONT
27mm offset with 8” width vs.

AFTERMARKET FRONT
36mm offset @ 8.5” width = Difference of 15.35mm front -

Result: Slight poke

OEM REAR
40mm offset @ 8.5” width vs

AFTERMARKET REAR
44mm offset @ 9.5” width = Difference of 16.7mm

Result: Slight poke

Looks like they will fit but you will be a bit beyond the edge so-to-speak in terms of what I've seen regarding wheel spacer fitments and such. If you lower the vehicle, I'm wiling to bet it'll tuck in tightly. Shouldn't have rubbing issues in the rear. Front, depending on how low you go, could present an issue. But only if you are really dropping it. Even then, you could undersize the tires (in their range limit of course) and get away with a little more than you could otherwise. But yeah, looks like a good option!

[Intricate39]

Originally Posted by rostrata

Love some good Ray's. Very nice pick. So I went an did a little quick math with more accurate numbers rather than the shit I was pulling out of the air earlier. Here's what I've come up with:

OEM FRONT
27mm offset with 8” width vs.

AFTERMARKET FRONT
36mm offset @ 8.5” width = Difference of 15.35mm front -

Result: Slight poke

OEM REAR
40mm offset @ 8.5” width vs

AFTERMARKET REAR
44mm offset @ 9.5” width = Difference of 16.7mm

Result: Slight poke

Looks like they will fit but you will be a bit beyond the edge so-to-speak in terms of what I've seen regarding wheel spacer fitments and such. If you lower the vehicle, I'm wiling to bet it'll tuck in tightly. Shouldn't have rubbing issues in the rear. Front, depending on how low you go, could present an issue. But only if you are really dropping it. Even then, you could undersize the tires (in their range limit of course) and get away with a little more than you could otherwise. But yeah, looks like a good option!

Hmm. Not sure if I want it to poke out! If I ever lowered it I’d want to do the dinan 1” drop.

Did you see any other combo on the link that would result in less difference? Maybe 8” fronts, 9” rears? Mines RWD so really looking to pick up the traction there. Oddly enough the site actually lists the G20 as a possible fitment of the 8.5 fronts and 9 rears on the right hand side.

Again, thanks again for all the knowledge!!!

[Rob_G77]

Originally Posted by djaycemaster

my car came with 20 inch wheels with 225/35/r20 in the front and 255/30/r20 in the back.

I have the 20 inch 795M rims as well. The lower profile and higher pressure makes them exceptionally brutal on potholes. 19's are better suited for this car as a daily driver.

Rob

[Intricate39]

Originally Posted by Rob_G77

I have the 20 inch 795M rims as well. The lower profile and higher pressure makes them exceptionally brutal on potholes. 19's are better suited for this car as a daily driver.

Rob

Rob,

Thank you for the insight. I think I’m leaning towards the G025’s in 19x8.5 and 19x9’s. Trying to figure out if it’ll rub with the offsets available for those wheels. I’d like to go 9.5’s in the rear, but looks like I may get some poke which I’d like to avoid.

[rostrata]

Originally Posted by Intricate39

Hmm. Not sure if I want it to poke out! If I ever lowered it I’d want to do the dinan 1” drop.

Did you see any other combo on the link that would result in less difference? Maybe 8” fronts, 9” rears? Mines RWD so really looking to pick up the traction there. Oddly enough the site actually lists the G20 as a possible fitment of the 8.5 fronts and 9 rears on the right hand side.

Again, thanks again for all the knowledge!!!

Never as easy as it seems, right?

I see a couple that might work fine. Like the 9" 27mm offset (inset) and the 9 1/2" 44mm offset. The 10"+ are a little too aggressive in their offsets so those won't work.

You will need to run a tire size comparison calculator to figure out which wheels will accommodate the tire sizes you need to run to keep you within the 1% range.

[Intricate39]

Originally Posted by rostrata

Never as easy as it seems, right?

I see a couple that might work fine. Like the 9" 27mm offset (inset) and the 9 1/2" 44mm offset. The 10"+ are a little too aggressive in their offsets so those won't work.

You will need to run a tire size comparison calculator to figure out which wheels will accommodate the tire sizes you need to run to keep you within the 1% range.

Rostrata,

Ok! So when you mentioned using a calc, I came across this one which does both offsets and tires.

https://www.1010tires.com/Tools/Wheel-Offset-Calculator#

Oddly enough. It says that if I were to change the fronts from (oem) 8” 27 ET to a 9” 32 ET it would be an extension of 8mm.

For the rears, going from an (oem) 8.5” 40 ET to a 9.5” 44ET would net a 9mm increase.

As anything under 10mm seems to sit flush, wouldn’t that work?

Is the tools math right? Also, looks like the inner clearances get compromised by 14-18mm respectively. Is this going to cause rubbing/strut clearance issues?

[Encanto]

Originally Posted by rostrata

Love some good Ray's. Very nice pick. So I went an did a little quick math with more accurate numbers rather than the shit I was pulling out of the air earlier. Here's what I've come up with:

OEM FRONT
27mm offset with 8” width vs.

AFTERMARKET FRONT
36mm offset @ 8.5” width = 3mm tucked in

Result: no poke, tucked in

OEM REAR
40mm offset @ 8.5” width vs

AFTERMARKET REAR
44mm offset @ 9.5” width = 9mm poke

Result: poke like using a 9mm spacer in the OEM wheels

Looks like they will fit but you will be a bit beyond the edge so-to-speak in terms of what I've seen regarding wheel spacer fitments and such. If you lower the vehicle, I'm wiling to bet it'll tuck in tightly. Shouldn't have rubbing issues in the rear. Front, depending on how low you go, could present an issue. But only if you are really dropping it. Even then, you could undersize the tires (in their range limit of course) and get away with a little more than you could otherwise. But yeah, looks like a good option!

Fixed for you.

[Intricate39]

Originally Posted by Encanto

Fixed for you.

That’s what I got as well. Which is why I was thinking the other front option (9” 32 ET) that gave 9mm would match better with the rears. Is it not advisable to move the front wheels out that much?

[Encanto]

Originally Posted by Intricate39

That’s what I got as well. Which is why I was thinking the other front option (9” 32 ET) that gave 9mm would match better with the rears. Is it not advisable to move the front wheels out that much?

For the G20, you can go up to a 9" ET20 wheel in the front, and a 9" ET25 in the rear for max flush, no poke. Add (subtract mathematically) ET2-3mm for a "hella flush" look -just poke enough with stretched tires and no rubbing.

You can play with the wheel width and the ET based on those limits with an offset calculator: https://www.1010tires.com/Tools/Wheel-Offset-Calculator

[Intricate39]

Originally Posted by Encanto

For the G20, you can go up to a 9" ET20 wheel in the front, and a 9" ET25 in the rear for max flush, no poke. Add (subtract mathematically) ET2-3mm for a "hella flush" look -just poke enough with stretched tires and no rubbing.

You can play with the wheel width and the ET based on those limits with an offset calculator: https://www.1010tires.com/Tools/Wheel-Offset-Calculator

Encanto,

So if I’m reading this right, the proposed sizes F: 9/32, R:9.5/44 will not work?

[Encanto]

Originally Posted by Intricate39

Encanto,

So if I’m reading this right, the proposed sizes F: 9/32, R:9.5/44 will not work?

The lower the ET, the more the wheel face is outside the fender line. The higher the ET, the more the wheel face is inside the fender line.

Your 9" ET32 front will be 8mm closer to the fender line than OEM, the rear 9.5" ET44 will be 9mm closer than OEM. This is like using a 8mm and 9mm spacers in your OEM wheels.

They will not be flush, but they will look better in the fenders than OEM. You need to check the inside clearance (wheel/tire distance from strut, or fender covers) before increasing wheel width and ET.

[larrylam646]

Originally Posted by Intricate39

Encanto,

So if I’m reading this right, the proposed sizes F: 9/32, R:9.5/44 will not work?

With the front wheel spec you are proposing - 9/32, I think you may have a clearance issue to the strut, depending on whether your M340i is equipped with adaptive suspension. Apparently, the adaptive strut diameter is greater than the non-adaptive.

If you go with 265mm wide tires on the front, I am almost certain the tire will rub on the strut with a 9/32. The 265mm wide tire may also rub on the inner fender liner when the steering is turned lock-to-lock.

Try using this tire wheel calculator to compare the proposed tire/wheel specs to your current setup to help you assess fit - https://www.wheel-size.com/calc/?whe...cl=30mm&sr=0mm.

Larry

[Intricate39]

Originally Posted by larrylam646

With the front wheel spec you are proposing - 9/32, I think you may have a clearance issue to the strut, depending on whether your M340i is equipped with adaptive suspension. Apparently, the adaptive strut diameter is greater than the non-adaptive.

If you go with 265mm wide tires on the front, I am almost certain the tire will rub on the strut with a 9/32. The 265mm wide tire may also rub on the inner fender liner when the steering is turned lock-to-lock.

Try using this tire wheel calculator to compare the proposed tire/wheel specs to your current setup to help you assess fit - https://www.wheel-size.com/calc/?whe...cl=30mm&sr=0mm.

Larry

Larry,

Thanks for the info. I may just stick with the earlier proposed 8.5/22 that actually bring it in a couple mm.

Any idea how those rears will fit? 9mm out, and 18mm inner clearance increase.

I do NOT have the adaptive, and I want to avoid any rubbing issues, but get the max amount of meat, especially on the rears.

[larrylam646]

Originally Posted by Intricate39

Larry,

Thanks for the info. I may just stick with the earlier proposed 8.5/22 that actually bring it in a couple mm.

Any idea how those rears will fit? 9mm out, and 18mm inner clearance increase.

I do NOT have the adaptive, and I want to avoid any rubbing issues, but get the max amount of meat, especially on the rears.

Rears on my M340iX is 265/35 on a 19x9.5 ET35. Plenty of clearance all around and tire/wheel does not poke (at the top of the fender). I think you can go with a more aggressive (lower) offset than ET44, if available.

What are you thinking about tire specs? I would recommend you try to keep the front/rear tire circumferences to be as close as possible... Critical for xDrive, less so for RWD. I just do not know how the DSC will behave if the difference in circumference too great.

Larry