[tom2021]

I know it has been discussed in the forum.
I plan to trade in 4 cylinders 2017 F25.
I was thinking M40i as a step up, until I drove a loaner car yesterday: G01 30i.
It is pretty fast all right.
I did test drive G30 540i last year. G30 and M40i use the same engine:B58.
Based on memory, G30 540i with 330 hp engine is not much faster than G01 with 248 hp engine for driving in the city.
I may have to take more time comparing M40i and 30i.
Perhaps, 30i is already a step up. Why spend more money?

[EWL5]

If you think the 30i is "fast enough", then there's really no point upgrading to the 6-cylinder unless you really want a HUD and the Driving Assistance Pro Package.

I made a similar decision and can put the money I saved towards better audio down the road if I choose to keep the car longer.

[avi66]

Originally Posted by tom2021

I know it has been discussed in the forum.
I plan to trade in 4 cylinders 2017 F25.
I was thinking M40i as a step up, until I drove a loaner car yesterday: G01 30i.
It is pretty fast all right.
I did test drive G30 540i last year. G30 and M40i use the same engine:B58.
Based on memory, G30 540i with 330 hp engine is not much faster than G01 with 248 hp engine for driving in the city.
I may have to take more time comparing M40i and 30i.
Perhaps, 30i is already a step up. Why spend more money?

Only you can decide if the extra is worth it for you. There's a 1.6 second difference to 60MPH, which may not sound much, but it is, and the straight 6 is a much smoother engine.

My advice is to test drive an X3 M40i and compare rather than depend on the memory of a different car some time ago.

[ASAP]

Originally Posted by avi66

Only you can decide if the extra is worth it for you. There's a 1.6 second difference to 60MPH, which may not sound much, but it is, and the straight 6 is a much smoother engine.

My advice is to test drive an X3 M40i and compare rather than depend on the memory of a different car some time ago.

oh god... this discussion again...

There is a 15 MPH difference in trap speed at the end of the 1/4... that is a larger difference than the difference between an m40i and an X3M comp... in a roll race... the 30i would not be able to see the m40s taillights...

this is why 0-60 is such a poor metric

[M40i4me]

Personally I love blowing the doors off hot shot kids in Civic SI’s and any other unsuspecting victims. Seriously for a daily driver no one needs an M40i until they drive one. Permanent smile every time…..

[avi66]

Originally Posted by ASAP

oh god... this discussion again...

There is a 15 MPH difference in trap speed at the end of the 1/4... that is a larger difference than the difference between an m40i and an X3M comp... in a roll race... the 30i would not be able to see the m40s taillights...

this is why 0-60 is such a poor metric

So, is that a long way to say the M40i is noticeably faster, as that was my only point.

[ASAP]

Originally Posted by avi66

So, is that a long way to say the M40i is noticeably faster, as that was my only point.

each version of the X3 is dramatically faster than the one below it... for the gas motors of course

[bcwalks2]

The 30i and 40i are not in the same galaxy. The 40i blows the doors off the 30i. You are talking about a normal 4 banger SUV that is similar to any other 4 banger turbo vs. a sport SUV with almost 400HP. I can tell you when my brother drove my 40i, he couldn’t believe it compared to his 30i. Only way to tell would be to drive them side by side. The 30i is plenty quick, but these are two totally different vehicles.

[ContactPatch]

Look, the BMW is ahead, enough said:

[Flippco]

Originally Posted by M40i4me

Personally I love blowing the doors off hot shot kids in Civic SI’s and any other unsuspecting victims. Seriously for a daily driver no one needs an M40i until they drive one. Permanent smile every time…..

This right here! It’s night and day diffrence between the 30i and 40i. It’s great being able to take most cars on the road although I have seen a few Audi R6 Avants lately and I would fully expect that to blow my doors off.

[dmicah]

Originally Posted by M40i4me

Personally I love blowing the doors off hot shot kids in Civic SI’s and any other unsuspecting victims. Seriously for a daily driver no one needs an M40i until they drive one. Permanent smile every time…..

I love the guys in the WRX's. They're realllllly slow,

[Poppyboy]

I have HUD in my 30i. Having driven both, the m40i wasn’t worth the price difference and I don’t crave validation from blowing the doors off another car.

[deviation01]

I recently drove 30i while my m40i was in the shop. The difference is really night and day to me. Yes the 30i is not bad but top end it dies.

[bbb83]

If you think 30i is fast I’d cross shop some minivans.

[bocabimmer]

Originally Posted by bbb83

If you think 30i is fast I’d cross shop some minivans.

I’ll write a counterpoint. Compared to the N20 the B46 is a much improved engine. It’s smoother, quieter, more reliable, and a better power delivery. I skipped the N20 entirely because I hated it. I almost skipped the B46 out of prejudice until I drove the LCI F30.

If you need confirmation that the B46 is good, go drive a minivan, go drive a Honda CR-V. You’ll be back quick (hint: I make that comparison on a weekly basis when I have to drive the minivan).

I’m not arguing that the trap speed isn’t ridiculously better, or even the 0-60. They are. And for the record, I’d rather have the B58. Heck, I’d rather have the true M engine. But two things come into play: budget and real world use cases.

I’d rather not spend the $9k price difference for the extra cylinders when I won’t see the benefit. My daily drive doesn’t consist of cases where I’m racing other cars, going flat out, and half the time I’m on roads that are decided more by who has the better suspension/steering/tire setup than horsepower.

If you find yourself in any of those categories, the 30i is an absolutely great choice and still better than many other cars on the road. Just know that you made that choice content that the M40 is better.

[turbobeagle]

One thing that I noticed is that the 2.0T engines rev high when in sport mode. It feels “uncomfortable”. To the point where I would never just leave the car set to sport mode unless I am really meaning to drive hard.

In contrast, on the 3.0T engines, you can put the transmission into the sport (not sport plus) mode, and the RPMs don’t shoot up. I can easily drive in that mode all the time if desired. And in fact I do just that. It’s very satisfying in terms of responsiveness, and you don’t feel like you’re a juvenile.

I do not drive hard, but even in lower speed / lower power situations, the bigger engines just feels so much better. I love getting a nice shove in the back of the seat without the engine having to rev up. When I got a 330i loaner, I was impressed at the power at full throttle, but in regular driving, I didn’t like having to keep revving it out.

[glennbk]

Really depends on what you want in a car. If you're constantly entering and exiting freeway ramps, want acceleration without WOT, smooth and reliable engine, go with the Six. There was no way in hades I was going to drive an almost 4400 pound car with a four cylinder. Been there done that in a Tiguan. Don't understand why the Six is more reliable than the Four, but it is. More of an enotional point, buy you have worked your butt off the get where you are. Don't you want a bit of a reward for that?

[pr0gi]

The only reason I got the 40i is because it has 6 cylinders. I wish BMW kept the detuned version of this engine as a 30i like it was in the past. But as others said, yes, both cars are in different leagues. Everything about the 40i is better than the 30i. If you can go and test both cars one after another you will feel the difference. Reliability-wise, I guess on the same level. As for better fuel economy, it's probably in favor of the 30i, but not by much. If you don't mind the price gap go for the 40i.

[spangle1980]

"I may have to take more time comparing M40i and 30i."

You most certainly do :-). The points above about the 0-60 are pretty valid. For sure standing start and nailing it is a thing, but most driving profiles are best on "you're already moving then gun it". What I did when testing M40i vs. M40d was get both cars and do exactly (or as near as) the same route and driving style. i.e see you how feel when you start from standstill and gun it in both. Then be driving at like 30mph and smash the loud pedal, then 40+ etc...

You'll probably come to the conclusion the 40 is way better, but then you have to factor in how much cash you have, what toys you really want etc.. If you are ONLY driving round town you probably will come to a different conclusion.

Good luck.

[hearhear]

You alluded to driving in the city, and you really don’t need 6 cylinder for that. If you were daily commuting on the highway, then yes a 6 would make sense. But in town daily driving I imagine the 4 cylinder would be perfect. I’m getting my first BMW soon, the X3 30i 4 cylinder. Using it for in town daily driving mostly. For that purpose, if you’re watching your wallet, why spend several thousand more for two extra cylinders? Per the BMW US site:

4 cylinder 30i=
HORSEPOWER: 248
0-60 MPH: 6.0 SEC

6 cylinder M40i =
HORSEPOWER: 382
0-60 MPH: 4.4 SEC

You have to decide if those numbers justify the extra cash. Now what’s interesting is the fuel economy- it’s identical for both the 30i and M40i for city driving = 21 MPG. Even highway driving it’s only a 2 MPG difference.

[Lady Jane]

Originally Posted by hearhear

4 cylinder 30i=
HORSEPOWER: 248
0-60 MPH: 6.0 SEC

6 cylinder M40i =
HORSEPOWER: 382
0-60 MPH: 4.4 SEC

You have to decide if those numbers justify the extra cash. Now what’s interesting is the fuel economy- it’s identical for both the 30i and M40i for city driving = 21 MPG. Even highway driving it’s only a 2 MPG difference.

The 1.4 seconds difference will also cost about $10,000 more. Vote with your wallet.

[TXGrey]

Originally Posted by hearhear

You alluded to driving in the city, and you really don’t need 6 cylinder for that. If you were daily commuting on the highway, then yes a 6 would make sense. But in town daily driving I imagine the 4 cylinder would be perfect. I’m getting my first BMW soon, the X3 30i 4 cylinder. Using it for in town daily driving mostly. For that purpose, if you’re watching your wallet, why spend several thousand more for two extra cylinders? Per the BMW US site:

4 cylinder 30i=
HORSEPOWER: 248
0-60 MPH: 6.0 SEC

6 cylinder M40i =
HORSEPOWER: 382
0-60 MPH: 4.4 SEC

You have to decide if those numbers justify the extra cash. Now what’s interesting is the fuel economy- it’s identical for both the 30i and M40i for city driving = 21 MPG. Even highway driving it’s only a 2 MPG difference.

Believe the 4.4 BMW lists is being fairly generous…. Real world #s are probably more 4.1ish…. I may have simply gotten “lucky” with mine; but my stock M40i is fast as hell. We used to talk about this topic all the time back in the day in the two-wheel world. I’ve had 1000cc bikes that just weren’t very quick… and I’ve had 600cc bikes that would blow the doors off larger bikes (except for top-end obviously). Sometimes, you just get lucky with a car or bike on the day it rolled off the line.

Regardless - don’t over analyze it. I’ve driven both as well. If you don’t need the HP and weren’t planning on spending the extra cash, the 30i is fine for almost everyone’s needs. If budget isn’t a concern, and you enjoy displacement/HP, the 40i is a beast even in stock form.