[LoneStar]

I already had a M40i.

Do you like your 30i and what would you choose beyond money?

[Westside Guy]

Originally Posted by Horseman

I think this has been stated before, but I really doubt your decision between the two trims is going to be the weight difference, tire difference or anything else that we're getting into crazy amounts of detail.

Really comes down to... if you can afford the extra on an M40i, why wouldn't you? Is the 30i enough? YES. Get the looks, good amount of power, for less. If you want to save 10-20k, go with the 30i.

If you want the ///M badge, more power, better exhaust and more options go with the M40i. I just don't think that you'll feel an incredible amount of difference between the two trims in terms of weight distribution and handling until you put it on the track.

As I have mentioned in previous threads and posts, I had a test drive in a 30i that had just arrived at my dealer and ordered the M40i without ever driving one because I had a flashback to the days of GTO's, 442's, etc. and I knew I wanted the extra HP.

[Horseman]

Originally Posted by Westside Guy

As I have mentioned in previous threads and posts, I had a test drive in a 30i that had just arrived at my dealer and ordered the M40i without ever driving one because I had a flashback to the days of GTO's, 442's, etc. and I knew I wanted the extra HP.

For me, it just came down to cost and what we were willing to afford. Could I have afforded it? Yes. Did I want to? Not at the time. If I could have gotten the M40i, I would have.

[Westside Guy]

Originally Posted by Horseman

For me, it just came down to cost and what we were willing to afford. Could I have afforded it? Yes. Did I want to? Not at the time. If I could have gotten the M40i, I would have.

Patience is a virtue and I have a funny feeling that the M40i is in your future.

[Horseman]

Originally Posted by Westside Guy

Patience is a virtue and I have a funny feeling that the M40i is in your future.

I hope you're right. I'm looking to transition into a new job soon.

[stlcdr]

Cost/benefit analysis, really. Interior/comfort level is a wash (that is, a very high standard in both). The 40 is significantly more.

Depends on how much of a child you are. Do you look forward to that tire-breaking acceleration, or do you always drive at a sedate pace? (Not that the 30 is a slouch).

Personally, I always go for the highest performing if the money makes sense. Better to have it and not need it, as they say…

[_icarus]

Originally Posted by LoneStar

the weight difference of the complete engine is is around 50-60 kg and most of it is in the front, even before the axle (additional cooler and so on). There is no doubt about it, it is the same like the 3 or 5series with 4 or 6 pot, you feel it always - I had every variation of it.

And yes, you don't need to compare apples with apples, because it can't be, I do the maths:

30i
smaller brakes -15 kg unsprung mass -> 105 kg less sprung mass
smaller wheels (225/255 instead of 255/275) - 12 kg unsprung mass -> 85 kg less sprung mass
with this equippment you get curb weight -70 to 80 kg -> I checked a lot of tested 30i and 40i on scales (AMS in Germany and the CoC paper in EU states the real weight with specific equippment).

You forgot about the sport differential and the adaptive suspension. Combined these two probably add up as much weight as the brakes and wheels, especially since the eLSD uses a clutch pack and has a separate control unit.

If the weight difference in the engines was 50-60kg as you claim that would make the B48, which is a 2.0 engine, 10-20kg lighter than your mainstream 1.0L or 1.2L engine in use today. I'm sorry, but that's simply impossible.
I can see you really want to believe this, but keep an open mind. One engine weighing almost half of the other just doesn't make sense, not when both are inline and made out of the same material. If the terms of comparison were inline vs V and aluminum vs cast iron then that would definitely be possible, but it's not the case.

[DavesZupra4]

Originally Posted by Horseman

I think this has been stated before, but I really doubt your decision between the two trims is going to be the weight difference, tire difference or anything else that we're getting into crazy amounts of detail.

Really comes down to... if you can afford the extra on an M40i, why wouldn't you? Is the 30i enough? YES. Get the looks, good amount of power, for less. If you want to save 10-20k, go with the 30i.

If you want the ///M badge, more power, better exhaust and more options go with the M40i. I just don't think that you'll feel an incredible amount of difference between the two trims in terms of weight distribution and handling until you put it on the track.

I don't care about the meaningless M badge. I care about the lsd, and beautiful i6

[BEAR-AvHistory]

Originally Posted by Horseman

I hope you're right. I'm looking to transition into a new job soon.

Sounds like me who has never grown up and am thrilled about that. As I went for each promotion was thinking about what the next car would be.

Be 81 in two weeks & pretty much nothing left on the bucket list.

[Horseman]

Originally Posted by BEAR-AvHistory

Sounds like me who has never grown up and am thrilled about that. As I went for each promotion was thinking about what the next car would be.

Be 81 in two weeks & pretty much nothing left on the bucket list.

Successful long life! Love it. Yes…. I am very much still a kid at heart. I have a man-cave filled with game toys, statues and other items. I always dream about what’s next and think of ways on how to get there. Then I also realize I’m a little lazy and forget to actually go out and do it.

[LoneStar]

Originally Posted by _icarus

You forgot about the sport differential and the adaptive suspension. Combined these two probably add up as much weight as the brakes and wheels, especially since the eLSD uses a clutch pack and has a separate control unit.

If the weight difference in the engines was 50-60kg as you claim that would make the B48, which is a 2.0 engine, 10-20kg lighter than your mainstream 1.0L or 1.2L engine in use today. I'm sorry, but that's simply impossible.
I can see you really want to believe this, but keep an open mind. One engine weighing almost half of the other just doesn't make sense, not when both are inline and made out of the same material. If the terms of comparison were inline vs V and aluminum vs cast iron then that would definitely be possible, but it's not the case.

I don't believe it, I know it

AMS has weighed both with adaptive suspension, sport brakes, wide alloys and LSD, 59 kg difference.

Just put 59kg of concrete or 59 1 litre milk bottles under the hood, part of it before the front axle, and try it.

I would order small alloys and no sportbrakes -> more than 80 kg and as I mentioned, part of it unsprung mass (count it with factor 7).


https://www.auto-motor-und-sport.de/...hnische-daten/

https://www.auto-motor-und-sport.de/...hnische-daten/

[BEAR-AvHistory]

Originally Posted by LoneStar

I don't believe it, I know it

AMS has weighed both with adaptive suspension, sport brakes, wide alloys and LSD, 59 kg difference.

Just put 59kg of concrete or 59 1 litre milk bottles under the hood, part of it before the front axle, and try it.

I would order small alloys and no sportbrakes -> more than 80 kg and as I mentioned, part of it unsprung mass (count it with factor 7).


https://www.auto-motor-und-sport.de/...hnische-daten/

https://www.auto-motor-und-sport.de/...hnische-daten/

You keep saying this in various weights your have added to the front of the S30. Thing the full effect of any weigh gain will not directly load the front wheels on a car with close to a 50/50 balance. Unless you do a before & after corner weight measurement with the 59kg in various front end locations its just a WAG at to its effect on the car.

Think about this with your addons:

The LSD is located in the differential at the rear of the car, the bigger wheels & tires are at the rear of the car. The sport brakes & suspension are split front to rear with the calipers in front being heavier.

That said your point has no meaning when comparing the S30 to the M40. The M40 as designed is quicker/faster has a higher continuous turn rate than the S30.

Pretty much the same ability to stop on a single application of the brakes (S30 has a 2ft advantage from 70) while has much greater fade resistance over continuous high speed use & superior tires. The adaptive suspension on a street drive car makes it much more livable than a fixed performance suspension or better handling than a fixed comfort suspension.

On both cars all major mechanical parts are behind the front wheels which effects the true load on them.

Other thing is as they stand on an even up test by the same people (C&D) the M40 will generate 1.02G vs S30 1.00G turning force.

You also leave out that if there was any short fall in the M40's ability to turn with the S30 it will more than make it up in turn entry braking/traction & turn exit power.

Small brakes & tires just limit your ability to slow prior to a turn. If I can prepare to turn a 60mph & you can only make the same reduction from 50 I can brake later than you with more power & traction to apply more power to the turn exit.

There are a number of reasons why anyplace you want to measure it street, track, AutoX etc the M40 will get to the desired destination first with the same driver.

Nothing against the S30 just like nothing against My M40 with compared to my M4. Quicker/faster cars are just quicker & faster but tend to cost more money when of the same Nameplate

[gkgeiger]

Well OP, 79 posts later, have you decided with all the expert help you got?

[LoneStar]

yes, I keep going the M240i, haha! 1750kg bigfoot in a small car. It‘s so crazy that‘s good again.

Tendency is indeed to get a Z4 with least unsprung und sprung mass as possible and enough power. It‘s not for track days, it‘s not to break records on Nürburgring, it‘s just the wish for a nimble roadster and lightweigth driving experience, with lively feedback, I often missed after 5000 miles in the M40.

[Amadeo]

I have LSD, sport brakes, adaptive suspension plus every other option available on the M40 on my 30i.Been the only difference, the engine.
As I understand this configuration is not available in the US?.

The Z4 with the B48 engine, less weight and everything else like the M40, performs exceptionally well in curves.

[Geradeaus]

Easy decision for me between the two models as I hate the M40i exhaust pipes and the cerium trim. Now if they change the exhaust to a proper quad tail pipe I'd get the M40i in black trim and change the kidneys to aluminum.

I drive my car at a 3-7 level and the little 4-banger does everything I ask for. I'll never drive it on the Nurburgring road or a race track so I'll never miss the extra pop. Each to their own - enjoy!

[DavesZupra4]

Originally Posted by Geradeaus

Easy decision for me between the two models as I hate the M40i exhaust pipes and the cerium trim. Now if they change the exhaust to a proper quad tail pipe I'd get the M40i in black trim and change the kidneys to aluminum.

I drive my car at a 3-7 level and the little 4-banger does everything I ask for. I'll never drive it on the Nurburgring road or a race track so I'll never miss the extra pop. Each to their own - enjoy!

Cerium sucks but you can option it in black.I'm getting the double slit black bumpers anyway soon.

Please don't tell me you think the chrome bumpers looks better. Oh my God it's the most hideous bumper I've ever seen and I'm atheist

[StanDiego]

Originally Posted by Amadeo

I have LSD, sport brakes, adaptive suspension plus every other option available on the M40 on my 30i.Been the only difference, the engine.
As I understand this configuration is not available in the US?.

Those options are available on the 30i in the U.S. HUD wasn't available on the 30i for 2022 models but it's back for 2023 models. The only option I'm aware of that's not available on the 30i in the US is the Frozen Grey II paint.

[BEAR-AvHistory]

Originally Posted by DavesZupra4

Cerium sucks but you can option it in black.I'm getting the double slit black bumpers anyway soon.

Please don't tell me you think the chrome bumpers looks better. Oh my God it's the most hideous bumper I've ever seen and I'm atheist

There is a rumor that my granddaughter is getting me a black grill for Christmas. Will add the black end caps to finish the look.

[_icarus]

Originally Posted by LoneStar

I don't believe it, I know it

AMS has weighed both with adaptive suspension, sport brakes, wide alloys and LSD, 59 kg difference.

Just put 59kg of concrete or 59 1 litre milk bottles under the hood, part of it before the front axle, and try it.

I would order small alloys and no sportbrakes -> more than 80 kg and as I mentioned, part of it unsprung mass (count it with factor 7).


https://www.auto-motor-und-sport.de/...hnische-daten/

https://www.auto-motor-und-sport.de/...hnische-daten/

It doesn't work that way. If you compute the weights from the numbers in those links you get 801KG on the front axle for the M40i and 742 for the 30i, a difference of 59 kg - you're absolutely correct here. However you drew the wrong conclusions.
That does not mean the B58 engine is 59kg heavier, it means there's 59kg more on the front axle. As we agreed the brakes and alloys are heavier, and the engine is longer which means it's putting a larger proportion of its weight on the front axle. So that 59kg difference on the front axle is coming from a combination of factors, not sheer engine weight.

Once again, to clarify: I'm not saying the M40i doesn't have 59kg more on the front axle. It clearly does as evidenced by the documentation you provided.
I'm saying that it's impossible for the engine to be 59kg heavier. Big distinction there.

[LoneStar]

Originally Posted by _icarus

It doesn't work that way. If you compute the weights from the numbers in those links you get 801KG on the front axle for the M40i and 742 for the 30i, a difference of 59 kg - you're absolutely correct here. However you drew the wrong conclusions.
That does not mean the B58 engine is 59kg heavier, it means there's 59kg more on the front axle. As we agreed the brakes and alloys are heavier, and the engine is longer which means it's putting a larger proportion of its weight on the front axle. So that 59kg difference on the front axle is coming from a combination of factors, not sheer engine weight.

Once again, to clarify: I'm not saying the M40i doesn't have 59kg more on the front axle. It clearly does as evidenced by the documentation you provided.
I'm saying that it's impossible for the engine to be 59kg heavier. Big distinction there.

Both cars in AMS had adaptive suspension and sport brakes

60 kg is nearly the truth of engine with aggregates and in-/outtake and OPF.

[R3R]

if I read the AMS data correctly:

2019 Z4 S Drive 30i M Sport 1518 kg as tested, 49.3%/50.7% or 748 kg/770 kg front/rear

2019 Z4 M40i 1577 kg as tested, 50.8%/49.2% or 801 kg/776 kg front/rear

That comes up to an additional 801-748=53 kg over the front axle and 776-770=6 kg over the rear axle.

The cars share same suspension (ground clearance 117 mm), eLSD and wheels (tire sizes 255/35 R 19 Y / 275/35 R 19 Y).