[f32458]

I am an E92 M3 DCT owner I am in the market for M235i auto or A45 AMG. ( same engine and gear box as CLA45 ) Is the 4 banger really lack of throttle response? Isn't that the future? I know Porsche is going to use them on macan, compact panamera, and face lift boxster/cayman. I have zero experience with N54 and N55. Realistically, I like both cars but I would love to know some proper answers.

[GoingTooFast]

Originally Posted by leon1984

0-60 time doesn't make something exciting, you seem to be passionate about vehicle weight and 'fun' hence not wanting big 6cyl engines which I can relate too but quoting a 0-60 time saying it's not bland because of that doesn't add up.

As of today's technology NO bland internal combustion engine can move a 1585 kg car from 0 to 62 mph as quickly as 4.6 s. NO WAY!!!

Moreover, the AMG turbocharged inline-4 pulls eagerly above 6000 rpm up to its redline, whereas my 1M's engine CLEARLY starts to run out of breath above that rpm.

[Wheelwright]

Originally Posted by f32458

I am an E92 M3 DCT owner I am in the market for M235i auto or A45 AMG. ( same engine and gear box as CLA45 ) Is the 4 banger really lack of throttle response? Isn't that the future? I know Porsche is going to use them on macan, compact panamera, and face lift boxster/cayman. I have zero experience with N54 and N55. Realistically, I like both cars but I would love to know some proper answers.

Follow what bradleyland has to say in this thread and you'll have real answer. 4-banger will never have as quick throttle-response as larger 6-cylinder engine assuming each engine is engineered at the same level. It's simple physics of volumetric efficiency and exhaust airflow.

It also perfectly explains why DSG gearbox in CLA45AMG is criticized for being so slow. It is extremely unlikely that Mercedes engineered a slow-shifting DSG given their technical supremacy. The real reason is that when DSG commands the engine to match the revs it has to wait for the sluggish boost to build up before it can engage the next gear. There is your slow throttle response in action.

No wonder CLA45AMG is not equipped with manual gearbox and never will be: without DSG to blame its laggy throttle would be laid bare. And that's the last thing Mercedes wants for its engine: being put in the same category as overboosted ricer Civic from the 90s which it essentially is.

[f32458]

Thanks for the reply. So N55 on the M235i reacts quicker and it has two more cylinders, and a larger displacement. How is it compare in real world against M133? I am betting it's much easier to tune N55 than M133? I am reading humongous hp/tq bump from after tuners for the AMG's. Perhaps this has something to with the engine made with forge materials by AMG? While N55 is just a regular production engine? Lastly, How is the 8 speed auto holding up? I never liked my 2010 C63's auto tranny. It was a junk.

[bradleyland]

Originally Posted by f32458

I am an E92 M3 DCT owner I am in the market for M235i auto or A45 AMG. ( same engine and gear box as CLA45 ) Is the 4 banger really lack of throttle response? Isn't that the future? I know Porsche is going to use them on macan, compact panamera, and face lift boxster/cayman. I have zero experience with N54 and N55. Realistically, I like both cars but I would love to know some proper answers.

You'll have to go and drive it for yourself. It's not like the A45 is a dog or anything, but you can definitely tell that it's a turbocharged engine. It's possible (probable even) to catch the engine in a bad spot where it feels a bit like an EVO or STi. You press the gas pedal and wonder when the torque will show up. It doesn't happen all the time, but it happens.

It is far more difficult to catch the N55 flat-footed, but it doesn't deliver the same intensity of acceleration all the way through redline. I'd say that the M133 in the A45 AMG delivers a higher level of intensity, in exchange for some difference in character.

There are definite, objective differences between the car, but which one you buy depends on what's most important to you. They're different enough cars when you drive both, I think it will be obvious which one you want. They're both fantastic cars.

[GoingTooFast]

These guys are not for real... how come someone says he is in the market for an A45 AMG implicitly stating at the same time that everything is better about the N55 engine?! I've heard this, I've heard that... what do you like about the 45 AMG then?


As for the 7G-DCT being sluggish, this only happens on Manual mode downshifts at high revs and you can observe the exact same feature on the MUCH less powerful also automatic only CLA 250 which is equipped with a VERY different engine running a MUCH lower boost, thus it's clearly not a characteristic of the AMG 4cyl. engine. Everyone genuinely interested should try it for themselves.

But people are free to believe in what they want so... let's the show continuing...

[bradleyland]

Originally Posted by f32458

Thanks for the reply. So N55 on the M235i reacts quicker and it has two more cylinders, and a larger displacement. How is it compare in real world against M133? I am betting it's much easier to tune N55 than M133? I am reading humongous hp/tq bump from after tuners for the AMG's. Perhaps this has something to with the engine made with forge materials by AMG? While N55 is just a regular production engine? Lastly, How is the 8 speed auto holding up? I never liked my 2010 C63's auto tranny. It was a junk.

Yes, the larger displacement of the N55 means the engine develops more force when off-boost. There is also more exhaust energy that can be used to drive the N55's relatively small turbos.

When it comes to tuning, the equation is a bit more complex. For example, forged internals don't get you a lot of power increases on their own. They reduce reciprocating mass and increase strength, so you can run more post and turn more RPMs. That results in more power. So the tuning potential of the M133 looks good.

However, you're still working with a base displacement of 2.0L. You can push a 2.0L engine to 700, 800, or even 900 HP. The M133 might even have the strength to handle those numbers, but those numbers won't come without a sacrifice. Have a look at the dyno plot for a small-displacement I4 that makes over 400 HP. You'll notice that the torque curve looks like a spike. You make a lot of power over a very small area of the RPM range. Personally, I have no desire to ever own a car like that, but plenty of other people do. Nothing wrong with that. It's just not the choice I'd make. You have to decide what your priorities are and go for it.

[bradleyland]

Originally Posted by GoingTooFast

It's a marketing thing... with NO meaningful dynamic advantage and VERY important disadvantages.

This is factually incorrect.

The advantage is clear illustrated by in-gear acceleration times for the M135i vs the CLA 45 AMG. I'd use the M235i as an example, but I haven't seen instrumented test yet. There is no reason to believe it will perform worse though.

Your entire argument is predicated upon this incorrect claim of fact. Until you rectify that, you haven't a leg to stand on.

You keep reasoning in black-and-white:

Turbocharging is either good or bad.

Four-cylinder engines are either good or bad.

Throttle response is either good or bad.

The CLA wins or loses.

I'm not sure how you make it through daily life with this kind of attitude. There is clearly a continuum here. The throttle response of the N55 is worse than, for example, the N52. However, the N55's throttle response is better than the M133.

The N55 makes far more power than the N52, yet there are plenty of members of the Bimmerpost forums who chose the 128i over the 135i, because they preferred the character of the N52. That's a valid choice.

Porsche clearly has a higher level of commitment to driving character than BMW. I'm not sure there are many people here who would argue against that. But again, the world is not black & white. Just because Porsche has a high level of commitment to driving character does not mean that BMW has zero commitment to similar values.

[GoingTooFast]

Originally Posted by bradleyland

Yes, the larger displacement of the N55 means the engine develops more force when off-boost. There is also more exhaust energy that can be used to drive the N55's relatively small turbos.

Small turbo... there's only ONE turbo on the N55 engine. It's the N54 that has two turbos, one for each cylinder bank and even then, because they are so small, they cannot make the engine breadthe well enough above 6000 rpm making the 7000 rpm redline rather pointless... another marketing thing?!

[pikcachu]

Originally Posted by GoingTooFast

These guys are not for real... how come someone says he is in the market for an A45 AMG implicitly stating at the same time that everything is better about the N55 engine?! I've heard this, I've heard that... what do you like about the 45 AMG then?


As for the 7G-DCT being sluggish, this only happens on Manual mode downshifts at high revs and you can observe the exact same feature on the MUCH less powerful also automatic only CLA 250 which is equipped with a VERY different engine running a MUCH lower boost, thus it's clearly not a characteristic of the AMG 4cyl. engine. Everyone genuinely interested should try it for themselves.

But people are free to believe in what they want so... let's the show continuing...

From someone that thinks that Kamui Kobayashi is better than Alonso or Hamilton I can now understand your opinions about the CLA engine

At least your opinions are consistent although a bit in denial....you remind me of some other guy with his 135is

but to each its own... you can think whatever your want ....

[GoingTooFast]

I guess I have to repeat myself...

Originally Posted by GoingTooFast

I think everyone who eats with a fork can understand what I'm saying...

If throttle response quality was BMW's first priority with their petrol engines, if that was absolutely critical, they would never have abandoned naturally aspirated engines in favor of turbocharged ones just like Porsche did so far on their most sportier (non-turbo) S and GT3 models which would be the equivalent to the M Performance and M models on BMW's lineup.

Moreover, even on the high displacement, 6-cyl. engine of the 911 Turbo Porsche went as far as to use two VGTs (Variable Geometry Turbochargers - one for each cyl. bank) which, again, are widely used on diesel engines for a long time now, with the sole objective of favoring the throttle response quality even if at the expense of some reliability, since exhaust gases temperatures are MUCH higher on petrol than diesel engines which is ALWAYS critical for any moving parts to withstand faultlessly, let alone VGTs.

BUT now Porsche felt that the 4-cyl. turbocharged petrol engines technology is such that they are going to adopt it first on theirs new entry-level models such as the Boxster and the Cayman and even admitting that the turbocharged 4-pot is good for as much as 400 hp on a future high-boost top performer version of both the Cayman and Boxster, which would be the equivalent to BMW's upcoming M2.

Once again, BMW is lagging behind... they will loose for the CLA because RWD alone is not enough to automatically classify a car as having a sportier character.

BMW has to concentrate themselves on a truly weight reduction program for, at least, their entry-level M models of which, smaller, lighter, lower COG and more fuel-efficient turbocharged 4-cyl. engines must be integral part if they want to beat the competition.

[GoingTooFast]

Originally Posted by pikcachu

From someone that thinks that Kamui Kobayashi is better than Alonso or Hamilton I can now understand your opinions about the CLA engine

I hope that you can at least understand that Ferrari and Mercedes or any other F1 car that has officially been driven by either Alonso or Hamilton was consistently a much better car than whatever car Kobayashi has ever officially driven during a F1 championship.

This season is no exception... but providing that the necessary reliability is there the driver's role is now of much greater importance... so, let's see...

[Red Bread]

So it's not his fault that his teammates consistently seem to be capable of avoiding other cars, something Kobi seems completely incapable of? If he were the only car on the track, I just assume he'd smash through a barrier and drive into a car in the carpark.

[pikcachu]

Well if he is that good... then why did he never got to drive a better car ?

[GoingTooFast]

Originally Posted by pikcachu

Well if he is that good... then why did he never got to drive a better car ?

Oh... if life could be fair... money rules... money rules!

Kobayashi cleared over first-lap accident 16 Mar 2014

Caterham’s Kamui Kobayashi has been cleared of any blame over his first-lap clash with Williams’ Felipe Massa in Australia in Sunday.

The Japanese driver had been summoned to the stewards after crashing into the back of Massa’s car as the pair approached the first corner of the race, eliminating both cars on the spot.

However, having reviewed technical data provided by Caterham, the stewards determined that the incident was ‘caused by a serious technical failure completely outside the control of the driver’.

Caterham have been directed to work with the FIA technical delegate Jo Bauer to determine the cause of the systems failure.

Kobayashi explained on Twitter that no rear brakes had been the problem, adding: "Sorry to Felipe but was not my mistake."

[leon1984]

Yawns…. read the whole post, I drove the M235 auto which does it in 4.8 and yes - I found it a dull experience. Fast, but too efficient, totally flat torque curve and seamless gear shifts…

It is possible for a fast car to not be exciting.

Bored talking to you now

Originally Posted by GoingTooFast

As of today's technology NO bland internal combustion engine can move a 1585 kg car from 0 to 62 mph as quickly as 4.6 s. NO WAY!!!

Moreover, the AMG turbocharged inline-4 pulls eagerly above 6000 rpm up to its redline, whereas my 1M's engine CLEARLY starts to run out of breath above that rpm.

[GoingTooFast]

Originally Posted by leon1984

Yawns…. read the whole post, I drove the M235 auto which does it in 4.8 and yes - I found it a dull experience. Fast, but too efficient, totally flat torque curve and seamless gear shifts…

It's not the engine you find bland since you've told you loved driving the manual version of the M135i which has the very same engine... it's the M235i's automatic transmission you've found dull, as stated by you.

[BMoney]

Originally Posted by bradleyland

Have a look at the dyno plot for a small-displacement I4 that makes over 400 HP. You'll notice that the torque curve looks like a spike. You make a lot of power over a very small area of the RPM range. Personally, I have no desire to ever own a car like that, but plenty of other people do. Nothing wrong with that. It's just not the choice I'd make. You have to decide what your priorities are and go for it.

I'm not sure that applies to the CLA45 at least at 400 HP. I have one with Eurocharged tune and it has a pretty flat tq curve and makes power all the way to redline.

[bradleyland]

Originally Posted by GoingTooFast

Small turbo... there's only ONE turbo on the N55 engine. It's the N54 that has two turbos, one for each cylinder bank and even then, because they are so small, they cannot make the engine breadthe well enough above 6000 rpm making the 7000 rpm redline rather pointless... another marketing thing?!

I meant N55 powered cars in general, but I'll give you that one, Mr. "Loss, Loss situation".

[bradleyland]

Originally Posted by BMoney

I'm not sure that applies to the CLA45 at least at 400 HP. I have one with Eurocharged tune and it has a pretty flat tq curve and makes power all the way to redline.

Originally Posted by BMoney

I'm not sure that applies to the CLA45 at least at 400 HP. I have one with Eurocharged tune and it has a pretty flat tq curve and makes power all the way to redline.

I haven't driven a tuned CLA45, so I can't say with authority whether it makes a difference, but a dyno plot is conducted under constant load, so the torque curve shouldn't be interpreted to provide insight in to throttle response. When the engine is under load, the turbo is spooled. The in gear acceleration times for the CLA 45 aren't as good as the M235i. That's probably the best measure of the difference in flexibility and responsiveness of the two engines.

I want to back up a second and make sure our boy here (not you, btw) hasn't pigeonholed me in to a position that I don't hold. The CLA 45 AMG is an incredible car. From a pure performance standpoint, I felt like it bested the M235i when I drove them literally a few days apart. When prodded, the CLA 45 delivers. I don't think any of its flaws are terminal. Not by any stretch.

It just has a different character, and part of that character is inherent to the physics involved. Twin-scroll turbos are an improvement, but I can still feel a distinct difference between the two cars.

The difference between me and GTF is that I refuse to adhere to his false dichotomy. I can understand why someone would choose either. The CLA 45 is incredible, and I'm sure anyone who chooses it will be thrilled with it. Likewise with the M235i.

[BMoney]

Originally Posted by bradleyland

I haven't driven a tuned CLA45, so I can't say with authority whether it makes a difference, but a dyno plot is conducted under constant load, so the torque curve shouldn't be interpreted to provide insight in to throttle response. When the engine is under load, the turbo is spooled. The in gear acceleration times for the CLA 45 aren't as good as the M235i. That's probably the best measure of the difference in flexibility and responsiveness of the two engines.

I want to back up a second and make sure our boy here (not you, btw) hasn't pigeonholed me in to a position that I don't hold. The CLA 45 AMG is an incredible car. From a pure performance standpoint, I felt like it bested the M235i when I drove them literally a few days apart. When prodded, the CLA 45 delivers. I don't think any of its flaws are terminal. Not by any stretch.

It just has a different character, and part of that character is inherent to the physics involved. Twin-scroll turbos are an improvement, but I can still feel a distinct difference between the two cars.

The difference between me and GTF is that I refuse to adhere to his false dichotomy. I can understand why someone would choose either. The CLA 45 is incredible, and I'm sure anyone who chooses it will be thrilled with it. Likewise with the M235i.

I haven't driven a non tuned CLA45 in 3 week so I can't remember much about how it drove before! Lots of complaints about throttle response from CLA45 owners so must be an issue. The tune has to help because throttle response for me is pretty good. Not on the level of my old C63 but it's not as described by others.

And for the record I don't agree with much of what GTF is saying!

[pikcachu]

wow those are nice numbers bmoney.... didn't think there was much left to squeeze on the CLA45 engine....