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Yes, when braking there is more weight on the front wheels. This is the same whether FWD, RWD, or AWD. And I never stated otherwise. :)

FWD and AWD understeer is a result of both driving the wheels and turning them at the same time. That is, there is less traction available for turning when some of the traction is already used for propelling the car.

And keep in mind, the majority of the time one is not driving in snowy/icy winter conditions. You are stuck with AWD the rest of the year when the roads are dry. I acknowledge for many this is no problem, but for me I hate the feel of an AWD car when the roads are perfect.


No, I live in a hilly area, including a 1/4 mile uphill driveway.


Position of an engine is biggest determinant of the level of understeer. When engine sites in front of an axle, you will always have excessive understeer, regardless of amount of torque front wheels are getting. Go push Audi Quattro in corners and than BMW xDrive in corners and you will see difference. Understeer in BMW xDrive in minimal and you will never notice unless you push car to absolute limit, even than it is easily managed. I had two BMW’s xDrive, both with diesel engines (heavier front) and they always drove like proper RWD based AWD vehicles. In slick, they will oversteer in no time, like any BMW.
And then you have Lexus IS, a RWD car with excessive understeer.

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Hi everyone. Living on the north coast of Ohio, almost all BMW's I see are xdrive, so I assumed that AWD was the way to go. However, I finally found the exact F33 that I am looking for but it is RWD. At first, I was hesitant, but I probably won't drive it in the snow anyway, since we have a beater Dodge Caravan. Also, I drove a RWD M3 last year and loved that way it handled.
My last BMW was an E30 RWD, many years ago, and I loved the way it drove in the curves. Do people think I am making a mistake by purchasing a RWD F33 rather than xdrive? Any comments and personal experience will be appreciated.
Thanks!
Hi ship4u! I also live in Cleveland and can tell you that my 335i paired with Michelin X-Ice has allowed me to drive in all the worst the NE-Ohio can dish out for the last 3 winters. If you are never going to autocross or track the car then get xDrive. It's another tool in the tool belt when you need it and if you ever take the car to the drag strip it'll launch like a monster. If you want to take on Cleveland winter with RWD go for it! With the right tires and adjustment to driving style you can drive arounds just fine.

I love my rwd 335i with its manual trans.
 

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Hi ship4u! I also live in Cleveland and can tell you that my 335i paired with Michelin X-Ice has allowed me to drive in all the worst the NE-Ohio can dish out for the last 3 winters.
You and Ship4U are lucky in your location. Koala Motorsports in Novelty (9988 KINSMAN RD, NOVELTY, OH 44072) is one of the premier BMW independents in the USA. If you feel frightened, go to them and get a limited slip diff installed. https://www.koalamotorsport.com/
 

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Position of an engine is biggest determinant of the level of understeer. When engine sites in front of an axle, you will always have excessive understeer, regardless of amount of torque front wheels are getting.
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These are interesting points. I think this discussion is more complicated than the cars weight distribution though it does play an important factor. How a given cars suspension is set up is very important as well. The cars camber, caster, toe, spring rate, and damper tuning are going to be key factors. The car's engine tuning and power delivery will be factors. The differential and electronic aids like the cars traction control, stability control, and having aids like torque vectoring are going to play a role as well.

Whether FWD, RWD, or AWD I'm sure you can find many examples of each platform that exhibit prodigious amounts of understeer. You can also find understeering examples of just about every engine layout between transversely mounted front engine ahead of the axle to rear engine mounted behind the axle. However the entire drivetrain and suspension package determine how the car drives. Keep in mind that just about every FWD car has an engine mounted ahead of the front axle.

Does a FWD cars engine layout mean it will have excessive understeer? I think the answer is no. Ask Golf GTI owners. Then again does a rear mounted mid-engine platform guarantee perfectly balanced understeer free handling? Again I believe the answer is no. Ask Lamborghini Huracan LP610-4 owners.
 

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You and Ship4U are lucky in your location. Koala Motorsports in Novelty (9988 KINSMAN RD, NOVELTY, OH 44072) is one of the premier BMW independents in the USA. If you feel frightened, go to them and get a limited slip diff installed. https://www.koalamotorsport.com/
Thanks for the heads up! I was starting to look for a good backup to the BMW dealership just in case I run into a maintenance task that I can't tackle.
 

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These are interesting points. I think this discussion is more complicated than the cars weight distribution though it does play an important factor. How a given cars suspension is set up is very important as well. The cars camber, caster, toe, spring rate, and damper tuning are going to be key factors. The car's engine tuning and power delivery will be factors. The differential and electronic aids like the cars traction control, stability control, and having aids like torque vectoring are going to play a role as well.



Whether FWD, RWD, or AWD I'm sure you can find many examples of each platform that exhibit prodigious amounts of understeer. You can also find understeering examples of just about every engine layout between transversely mounted front engine ahead of the axle to rear engine mounted behind the axle. However the entire drivetrain and suspension package determine how the car drives. Keep in mind that just about every FWD car has an engine mounted ahead of the front axle.



Does a FWD cars engine layout mean it will have excessive understeer? I think the answer is no. Ask Golf GTI owners. Then again does a rear mounted mid-engine platform guarantee perfectly balanced understeer free handling? Again I believe the answer is no. Ask Lamborghini Huracan LP610-4 owners.


Yes, those are all factors playing. But, it is much easier to “play” with all those things when engine sits back. There is much more room for fine tuning when there is proper weight distribution. Audi S4 B7 had engine far ahead and it was V8. It is extremely hard vehicle, uncomfortable, why? Bcs that heavy V8 was pushing vehicle outside all the time. Suspension had to be extremely complex, and forget any kind of comfort. Even B8 that has Supercharged V6 (an excellent engine, by the way) and that is pushed back a bit compared to B7, had to have double wishbone and some other trickery to limit understeer (though, B8 S4 is really well executed car I must say). Still regardless of vectoring differential, 40/60 split, you ALWAYS know it is oversteer car.
That is not the case with BMW xDrive.
But, as disclaimer, if AWD is not necessary, RWD is always better. I am on the market now for fun car, and contemplating E90 335i or F30 335i or if ai am able to swing, even 2016 340. But, I ski twice a week and sometimes 3 times, and drive up the Rockies. RWD would be a pain. But, if I was still in San Diego? RWD, all the way!



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Discussion Starter #47
You and Ship4U are lucky in your location. Koala Motorsports in Novelty (9988 KINSMAN RD, NOVELTY, OH 44072) is one of the premier BMW independents in the USA. If you feel frightened, go to them and get a limited slip diff installed. https://www.koalamotorsport.com/
Thanks for the recommendation. I will be looking for a good mechanic soon. :thumbup:
 

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Discussion Starter #51
follow up

Hi everyone,
As you can see, I decided that the RWD was a good option for me. Thanks for all of your thoughtful comments. I am really enjoying this car. The dealership in Tallahassee, Florida, was a pleasure to work with, and I had the car shipped here to Cleveland. :roundel:
 

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Great thread, so many good points. Having owned most of the configurations, I've experienced a good bit of the spectrum in snow. Also, having done a fair bit of autocrossing with a penchant for whippin' through the windy's at 8 or 9 10th's, I feel I can speak to the handling differences - weight distribution, over/understeer, RWD, FWD, AWD in snow, wet and dry. I've driven in snow/ice through eras in technology, from RWD (bad) to FWD (better) to AWD (best). This post might be a bit long, but a lot of this discussion is exactly why I ended up in the 428i x-drive and always run AS tires.

If you drive in snow, you can't count on a road being cleared, ice free, etc., and levels of snow in a given year are unpredictable. I've seen 25" of snow at the end of April in New England, just after switching to summer tires. Point is, you'll find yourself on your own in the snow often enough for it to really suck, so it pays to be ready.

Modern AWD is relatively inexpensive and an amazingly competent technology, with compromises that are actually minimal (or even non-existent) in the right platform. As long as I live in a snow-prone area, my daily drivers will have it. Arguing the performance compromise, I'd offer a 3800lb MS6 Touring at 3 seconds faster vs MX5 Miata on identical autocross layout, on a summer day, in the dry at a Zoom-Zoom Live events. Granted, the Miata was not a performance config, but the big 'ol MS6 just smoked it. The AWD clawed out of the corners, and understeer was very controllable with brakes, throttle and precision. Sometimes I think the real factor that day may have been the sticky Yokohama summer tires that came stock on the MS6, but could it explain a 3 second difference? Bottom line is, it had an AWD setup that was just formidable in the dry. With 276hp turbo 4, 6-speed manual and AWD it was actually very close (in spec, at least) to my 428i. Over the 13 years I owned it and never a single problem in snow, it became the bar. It was primarily FWD, transverse engine sitting on or slightly forward of the front wheels. AWD split was 50/50 max to the rear wheels. The center clutch could be disabled by pulling the handbrake one click, just till the brake light came on. The difference was noticeable in all conditions, but especially in snow.

So many factors do come into play, but tires really are the absolute in every road condition. Just like setting up a street car for the track or autocross, configuration for snow presents compromises. I took delivery of the MS6 with an extra set of Continental Winter Contact tires on 17" rims. The day after I bought it, (around Jan 6) I left CT for Minneapolis. It was phenominal. Too many times I left for work before the plow came through, sometimes pushing snow that was 3 or 4" deeper than my front end lip. Nothing in MN stopped the MS6 on full snows. The Conti's had hardened tread edges that bit into ice when they were newer. This went away a bit as the tires wore, and they wore fast in warm weather. Important to switch to summers as soon as spring comes. It should be noted that besides having zero grip in snow, summer compounds lose grip considerably in cold weather. I eventually replaced the Conti's with Pirelli AS 17" as an experiment, and then Cooper AS 17" when the Pirellis wore out. Specific season tires are costly, but especially the Yokohama summers. I took them off the rims, never got around to replacing the summers and I still have the 18" rims stored. The first sets both wore out in the same year, so I was looking at full replacement. The AS tires weren't as awesome as the full winters, but still quite good with the AWD and I never had to switch to summers/winters. I only spent that first winter in MN, and AS were fine in the relatively mild CT winters.

I traded a Mazda 3 hatch for the MS6, and the winter in CT had been mild. I procrastinated putting all seasons on the 3, and it was a scary ride in the least bit of snow. FWD, a crappy diff and summer tires gave these cars a well deserved bad winter reputation. Could barely get going on the flat from a traffic light on an inch of snow. IMO, all commuter/economy cars should ship with AS tires, at least in snow areas. That 3 just sucked in snow as delivered. AS tires would probably have helped, but I never found out.

I'm at the point where the goal is to never have to take the shovel out of the trunk, or to be anything less than confident in the worst snow conditions. I recently replaced the MS6 with my current 428i x-drive. When I went out shopping, the goal was replacing the MS6 with all it's superb capability and minimal compromises to dry performance (virtually none), and I wasn't about to take a step backward. I want it all, but I know I can't have all in one car. Maximising summer attributes while minimizing winter compromise, and tire choice above all seems to be key.

RWD - Full snow tires or you flirt with disaster. Even at that, put a shovel in the back seat so you don't have to go to the trunk so often. Sand helps too.
I have this vivid memory of watching a brown 5 series coupe sideways on a snowy Massachusetts interstate curve, couldn't have been doing more than 40mph, bounced off the guardrail, and probably on AS tires.
FWD - Most will eek by on AS, but full snows are best. You'll be getting stuck in any deep stuff, so it's best to have a shovel.
AWD/4WD - AS will get you there just about as well as full snows. Don't even bother on summers, it just spins all four wheels. I have shovels in the cars, never used it in the MS6 or the wife's AWD Flex, both on Cooper AS tires.

Finally, there's the stopping problem, where all the variants quickly become relatively equal. Stopping is probably where the discussion should start, really. Here, all drivetrain configs can be improved by full snows because the drivetrain does little to stop the car. Good, functioning ABS and DSC both help so long as you run at least AS tires. Here, full snows do a bit better. Tread stagger is bite, stopping and going. More rows and more stagger = more bite. Full snows are almost all staggered tread, Most AS tires have one or two staggered rows. Summers have none. The best full snow tires have big stagger and hardened tread edges that provide some bite on ice, and that's all about stopping. Very cold areas like MN and AK raise the argument for full snows for the extra bite on ice. Sun melts snow during the day, the water runs across the road and turns to ice, and there's occasional black ice, even in warmer areas.

Used to be that AWD/4WD was clunky, heavy and inefficient, used a lot of fuel, etc. Technology being what it is, today's compromises have less effect. I'm sure it's why SUV's have become the family car of choice, as most are on demand AWD/4WD, and fuel efficient. For me, a performance oriented vehicle with AWD, ABS, DSC and a set of AS ("M+S" on the sidewall) combination offers the best winter solution in most winter places without having to resort to full snows/summers. And with cars like BMW, WRX, Audi Quattro and MS6 (sadly out of production), they can be a great summer drive too.
 

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Great thread, so many good points. Having owned most of the configurations, I've experienced a good bit of the spectrum in snow. Also, having done a fair bit of autocrossing with a penchant for whippin' through the windy's at 8 or 9 10th's, I feel I can speak to the handling differences - weight distribution, over/understeer, RWD, FWD, AWD in snow, wet and dry. I've driven in snow/ice through eras in technology, from RWD (bad) to FWD (better) to AWD (best). This post might be a bit long, but a lot of this discussion is exactly why I ended up in the 428i x-drive and always run AS tires.

If you drive in snow, you can't count on a road being cleared, ice free, etc., and levels of snow in a given year are unpredictable. I've seen 25" of snow at the end of April in New England, just after switching to summer tires. Point is, you'll find yourself on your own in the snow often enough for it to really suck, so it pays to be ready.

Modern AWD is relatively inexpensive and an amazingly competent technology, with compromises that are actually minimal (or even non-existent) in the right platform. As long as I live in a snow-prone area, my daily drivers will have it. Arguing the performance compromise, I'd offer a 3800lb MS6 Touring at 3 seconds faster vs MX5 Miata on identical autocross layout, on a summer day, in the dry at a Zoom-Zoom Live events. Granted, the Miata was not a performance config, but the big 'ol MS6 just smoked it. The AWD clawed out of the corners, and understeer was very controllable with brakes, throttle and precision. Sometimes I think the real factor that day may have been the sticky Yokohama summer tires that came stock on the MS6, but could it explain a 3 second difference? Bottom line is, it had an AWD setup that was just formidable in the dry. With 276hp turbo 4, 6-speed manual and AWD it was actually very close (in spec, at least) to my 428i. Over the 13 years I owned it and never a single problem in snow, it became the bar. It was primarily FWD, transverse engine sitting on or slightly forward of the front wheels. AWD split was 50/50 max to the rear wheels. The center clutch could be disabled by pulling the handbrake one click, just till the brake light came on. The difference was noticeable in all conditions, but especially in snow.

So many factors do come into play, but tires really are the absolute in every road condition. Just like setting up a street car for the track or autocross, configuration for snow presents compromises. I took delivery of the MS6 with an extra set of Continental Winter Contact tires on 17" rims. The day after I bought it, (around Jan 6) I left CT for Minneapolis. It was phenominal. Too many times I left for work before the plow came through, sometimes pushing snow that was 3 or 4" deeper than my front end lip. Nothing in MN stopped the MS6 on full snows. The Conti's had hardened tread edges that bit into ice when they were newer. This went away a bit as the tires wore, and they wore fast in warm weather. Important to switch to summers as soon as spring comes. It should be noted that besides having zero grip in snow, summer compounds lose grip considerably in cold weather. I eventually replaced the Conti's with Pirelli AS 17" as an experiment, and then Cooper AS 17" when the Pirellis wore out. Specific season tires are costly, but especially the Yokohama summers. I took them off the rims, never got around to replacing the summers and I still have the 18" rims stored. The first sets both wore out in the same year, so I was looking at full replacement. The AS tires weren't as awesome as the full winters, but still quite good with the AWD and I never had to switch to summers/winters. I only spent that first winter in MN, and AS were fine in the relatively mild CT winters.

I traded a Mazda 3 hatch for the MS6, and the winter in CT had been mild. I procrastinated putting all seasons on the 3, and it was a scary ride in the least bit of snow. FWD, a crappy diff and summer tires gave these cars a well deserved bad winter reputation. Could barely get going on the flat from a traffic light on an inch of snow. IMO, all commuter/economy cars should ship with AS tires, at least in snow areas. That 3 just sucked in snow as delivered. AS tires would probably have helped, but I never found out.

I'm at the point where the goal is to never have to take the shovel out of the trunk, or to be anything less than confident in the worst snow conditions. I recently replaced the MS6 with my current 428i x-drive. When I went out shopping, the goal was replacing the MS6 with all it's superb capability and minimal compromises to dry performance (virtually none), and I wasn't about to take a step backward. I want it all, but I know I can't have all in one car. Maximising summer attributes while minimizing winter compromise, and tire choice above all seems to be key.

RWD - Full snow tires or you flirt with disaster. Even at that, put a shovel in the back seat so you don't have to go to the trunk so often. Sand helps too.
I have this vivid memory of watching a brown 5 series coupe sideways on a snowy Massachusetts interstate curve, couldn't have been doing more than 40mph, bounced off the guardrail, and probably on AS tires.
FWD - Most will eek by on AS, but full snows are best. You'll be getting stuck in any deep stuff, so it's best to have a shovel.
AWD/4WD - AS will get you there just about as well as full snows. Don't even bother on summers, it just spins all four wheels. I have shovels in the cars, never used it in the MS6 or the wife's AWD Flex, both on Cooper AS tires.

Finally, there's the stopping problem, where all the variants quickly become relatively equal. Stopping is probably where the discussion should start, really. Here, all drivetrain configs can be improved by full snows because the drivetrain does little to stop the car. Good, functioning ABS and DSC both help so long as you run at least AS tires. Here, full snows do a bit better. Tread stagger is bite, stopping and going. More rows and more stagger = more bite. Full snows are almost all staggered tread, Most AS tires have one or two staggered rows. Summers have none. The best full snow tires have big stagger and hardened tread edges that provide some bite on ice, and that's all about stopping. Very cold areas like MN and AK raise the argument for full snows for the extra bite on ice. Sun melts snow during the day, the water runs across the road and turns to ice, and there's occasional black ice, even in warmer areas.

Used to be that AWD/4WD was clunky, heavy and inefficient, used a lot of fuel, etc. Technology being what it is, today's compromises have less effect. I'm sure it's why SUV's have become the family car of choice, as most are on demand AWD/4WD, and fuel efficient. For me, a performance oriented vehicle with AWD, ABS, DSC and a set of AS ("M+S" on the sidewall) combination offers the best winter solution in most winter places without having to resort to full snows/summers. And with cars like BMW, WRX, Audi Quattro and MS6 (sadly out of production), they can be a great summer drive too.


Stopping is real problem.
As I say: I have never seen anyone die because of not being able to go fast enough forward. But I did see people die because they couldn’t stop fast enough.
Any regular winter, requires snow tires, regardless of drivetrain. Anyone who says: All Season are enough, are fools.



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