[Wheelwright]

Originally Posted by bradleyland

An engine makes it power from burning an air-fuel mixture. The more you burn, the more power you make. Because gasoline engines rely on a stoichiometric ratio of around 15:1, you must add air proportionally with fuel. This means that in order to make more power, you must move a greater volume of air. Your options are:

• Rotate the engine faster - loses efficiency to laminar flow issues at high velocity
• Increase the displacement of the engine - results in poor fuel economy because of wasted heat energy at lower loads
• Force more air in to the engine - requires additional energy to increase intake pressure

Turbocharging "cheats", because it uses wasted exhaust gas energy to drive the compressor, which increases intake pressure. However, there is only a limited amount of this exhaust energy available for a given displacement. This means that the more pressure you try to generate, the longer you'll have to wait for boost. That is the very formula for poor throttle response.

When designing an engine, you can preserve throttle response by using a larger base displacement, and keeping intake pressure levels low. This allows you to use smaller turbos, which spool up much faster. That is why a 3.0L I6 turbo can deliver 300+ HP with better character than a 2.0L I4 turbo can.

Thanks for the clear explanation. This makes perfect sense to me: larger displacement inherently creates more exhaust pressure which can spool up turbo quicker because there is less wait for the pressure to build up. You can't avoid the law of physics. This is confirmed by car reviews which consistently criticize small displacement turbo engines for their poor throttle response.

[GoingTooFast]

Originally Posted by Wheelwright

Thanks for the clear explanation. This makes perfect sense to me: larger displacement inherently creates more exhaust pressure which can spool up turbo quicker because there is less wait for the pressure to build up. You can't avoid the law of physics. This is confirmed by car reviews which consistently criticize small displacement turbo engines for their poor throttle response.

Then Porsche should learn from BMW how to build great sports cars because they haven't succeeded so far in doing so... give me a break!

Here's Porsche's answer to 'small displacement turbo engines poor throttle response' cliché... they are going to adopt it and in different guises, go figure :

http://www.worldcarfans.com/114032172143
/next-generation-porsche-boxster-and-cayman-confirmed-with

In an interview with Germany's Auto Motor und Sport magazine published on Thursday, 60-year-old Müller said Porsche road cars would follow the lead of the company's hi-tech 919 Hybrid race car in receiving four-cylinder engines.

But while the 919 Hybrid runs a unique V4 engine, the unit being readied for the Boxster and Cayman will follow the lead of Porsche's classic six-cylinder with a 180-degree horizontally opposed layout as part of a modular engine strategy.

[bradleyland]

Originally Posted by GoingTooFast

Then Porsche should learn from BMW how to build great sports cars because they haven't succeeded so far in doing so... give me a break!

Here's Porsche's answer to 'small displacement turbo engines poor throttle response' cliché... they are going to adopt it and in different guises, go figure :

http://www.worldcarfans.com/114032172143
/next-generation-porsche-boxster-and-cayman-confirmed-with

You're still missing the point (over, and over, and over again). It's not a simple matter of turbocharging or not. It's not a simple matter of displacement. It's a matter of just how far you can push an engine of a given displacement, without sacrificing too much throttle response.

The upper limit has been pushed upward by improvements in turbocharger technology, but the engine in the CLA 45 has, in my opinion, been pushed too far. It's that simple.

You're throwing up more strawmen with your Porsche example.

[leon1984]

I had to laugh at the BMW's don't turn in because they have a heavy front end!! haha… The position of the engine (rather than the weight of a 6cyl compared to a 4cyl) has a much bigger impact on the front tyres ability to turn the car..

What I don't understand, is going to great lengths to explain why the throttle response in high powered diesels is so poor and then wax lyrical about a 4 pot turbo engine which will suffer the very same fate.

Low boost, high displacement engines will always be much more flexible and responsive than a high boost 2ltr 4 cylinder engine. To think using a 6 cylinder is marketing tosh is just ridiculous.

It isn't like AMG have just invented this, there has been 900+ bhp 2.0 Evo's and the likes since the dawn of time and no - I wouldn't want one of those either.

[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]

So, if a turbocharged 4-cyl. engine is good enough for AMG and Porsche, why is BMW keeping the 6 cyl. engine on their 2-series?!

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

Buying a car today because it has a turbocharged 6-cyl. engine instead of 4 cylinders is a mute point when you can extract the same power from both but more efficiently so from the latter and without sacrificing throttle response in a significant way... BMW will learn it the hard way because their 2-series can't even look as luxurious as the CLA.

It's a loss, loss situation for BMW!!!

[Wheelwright]

If Porsche could get away with abominations such as Cayenne and Panamera it proves they can also get away with sucky throttle response as well. The reason is that way too many people buy purely based on badge.

Also because most of those buyers can't really drive they opt for automatic transmission with its programmed software tricks designed to hide poor throttle response. Of course software can only do so much because it still must operate within physical system limitations.

I suspect that's the real reason CLA45AMG DSG transmission is universally panned as sluggish, the throttle in that car is simply too slow to respond to the transmission's commands to match the revs. This also explains why CLA45AMG is not offered with manual transmission: it would expose the laggy throttle.

[leon1984]

You really are clueless.

Firstly, if you think 4WD makes a car 'sporty' then you are way off the pace. Every uneducated person flocks to buy "quattro" Audi's only to by essentially a FWD system that can at certain points, and pretty crudely transfer power to the rear wheels. Dynamically Audi's are very very poor, as most decent road testers will confirm. Doesn't stop average joe on the street thinking he has a 'cool fast car' because it is 4WD though does it?

The biggest downfall of the CLA, once you get past it's horrendous looks is a very bland 4 pot turbo engine. No character, no soul.

Originally Posted by GoingTooFast

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.

[BEM-S4]

Originally Posted by Wheelwright

If Porsche could get away with abominations such as Cayenne and Panamera it proves they can also get away with sucky throttle response as well. The reason is that way too many people buy purely based on badge.

Just curious, have you actually owned or driven any of these "abominations?" Sure both you mentioned don't handle like a track day GT3 but let's be honest, they're both top of their class for what they are. I had a Panamera for 6 months and loved it. Got a Macan on order.

[Wheelwright]

By "abominations" I meant styling. In my opinion they are grotesque Frankensteins of modern car design. I am sure they are well-enough engineered, especially later ones. Regarding styling there is hope too: Macan is much more cohesive than early Cayennes.

[BEM-S4]

Originally Posted by Wheelwright

By "abominations" I meant styling. In my opinion they are grotesque Frankensteins of modern car design. I am sure they are well-enough engineered, especially later ones. Regarding styling there is hope too: Macan is much more cohesive than early Cayennes.

The Macan is much better looking and I can't wait to get it. Yes those cars are hideous but the Panamera especially is an amazing car to drive for a bigger 4-door. I was at the NYC auto show black tie night discussing it w a very attractive female Porsche exec. She asked me my thoughts since I've driven and owned quite a few over the years. I told her, "it's like f*cking an ugly chick that's a great lay, it's awesome when you're inside but as soon as you're done and climb out you want to throw up when you see what you've just been inside." She laughed and we grabbed drinks later but I thought I was going to get slapped for a second. That's honestly the best way to describe both those cars.

[GoingTooFast]

Originally Posted by Wheelwright

I suspect that's the real reason CLA45AMG DSG transmission is universally panned as sluggish, the throttle in that car is simply too slow to respond to the transmission's commands to match the revs. This also explains why CLA45AMG is not offered with manual transmission: it would expose the laggy throttle.

You are wrong I'm afraid... AMG opted for a protective feature on downshifts at high revs in case you don't know what you're doing.

[GoingTooFast]

Originally Posted by leon1984

You really are clueless.

Firstly, if you think 4WD makes a car 'sporty' then you are way off the pace. Every uneducated person flocks to buy "quattro" Audi's only to by essentially a FWD system that can at certain points, and pretty crudely transfer power to the rear wheels. Dynamically Audi's are very very poor, as most decent road testers will confirm. Doesn't stop average joe on the street thinking he has a 'cool fast car' because it is 4WD though does it?

AWD, RWD, FWD you can have exceptional good driver's cars on each of these guises... that is not the decisive factor... it's NOT the car's ability to drift that turns it into the best driver's car, that is a gross misconception cherished by some show-off motoring press!!!

Originally Posted by leon1984

The biggest downfall of the CLA, once you get past it's horrendous looks is a very bland 4 pot turbo engine. No character, no soul.

0-62 mph in 4.6 seconds I wouldn't call it bland... which is something I cannot say about the M235i looks.

[Greenkirby21]

Originally Posted by GoingTooFast

AWD, RWD, FWD you can have exceptional good driver's cars on each of these guises... that is not the decisive factor... it's NOT the car's ability to drift that turns it into the best driver's car, that is a gross misconception cherished by some show-off motoring press!!!




0-62 mph in 4.6 seconds I wouldn't call it bland... which is something I cannot say about the M235i looks.

IMO the CLA45 4 cylinder is the least bland 4 cylinder engine I have heard! Lots of power and great sound for a 4 cylinder.

[pikcachu]

Originally Posted by GoingTooFast

AWD, RWD, FWD you can have exceptional good driver's cars on each of these guises... that is not the decisive factor... it's NOT the car's ability to drift that turns it into the best driver's car, that is a gross misconception cherished by some show-off motoring press!!!




0-62 mph in 4.6 seconds I wouldn't call it bland... which is something I cannot say about the M235i looks.

Well I take "bland" any day before just plain ugly like the CLA rear..... front is pretty good but the back is just ridiculous

The CLA makes a lot of power...if you don't mind the throttle response then it might be good for you....

but the I6 sounds nicer and is more responsive.... why can't you understand some people prefer that ? and keep going over and over and over .....

[GoingTooFast]

Originally Posted by pikcachu

The CLA makes a lot of power...if you don't mind the throttle response then it might be good for you....

but the I6 sounds nicer and is more responsive.... why can't you understand some people prefer that ? and keep going over and over and over .....

Most of you are so concerned about defending BMW that you don't even listen... the throttle response of the CLA's engine is fine BUT I would never buy a car such as the CLA AMG or the M235i for that matter.

They belong to the same league. One is not sportier than the other, it just happens that one looks and is more expensive and also faster.

You see, as an 1M owner I miss the first time I drove a BMW, I miss the E36 318is Coupé, I miss that lightness sensation, the feeling of being totally connected to the car as one, the low seating position, the dashboard oriented towards the driver, everything gravitating around you, that nimble sensation as you turned the steering wheel into a corner with the throttle dictating the chassis behavior in perfect harmony with your momentary state of mind.

Yes, it wasn't a 6-cyl. engine; yes, it wasn't a high capacity engine; yes, it wasn't a very powerful or sophisticated engine; yes, it lacked a limit slip differential; yes, it wasn't the fastest car around, far from it; yes, now that I have all of that I still miss the red E36 318is Coupé on the optional sport suspensions.

It's time to go back to that era with lightweight 4-cyl. engines and chassis... that's what will make all the difference, that's what the 1M didn't help me to forget!

[GoingTooFast]

Originally Posted by Greenkirby21

IMO the CLA45 4 cylinder is the least bland 4 cylinder engine I have heard! Lots of power and great sound for a 4 cylinder.

Yes. But BMW shouldn't go that route with the M2. Such a powerful 4 cyl. engine is not needed as long as BMW can lower the overall car weight in a meaningful way. Increasing the engine power only will make things more difficult than they are now...

Originally Posted by Dackelone

@Advevo

^^Google translation...

BMW does not have a race-2er delivered - despite commitment and Cup bid.

Sportscar info:

"The delivery of the first 15 cars have now been announced for next Wednesday. Three days before the first race of the VLN Endurance Championship 2014. (..) "

And when they come, then without lifting plant:

"Evil tongues say but that Bayern had always problems to achieve the targeted weight of 1400 kg and a further weight driver in the form of lifting plant would not have made the problem smaller."

Since BMW was going to a little bit of crisis management good to face. The idea of the car was fired on all channels, the teams have ordered diligently - and now envelops you in silence.

If you ever noticed that there is no weight in the technical data? In a RACE? Even in facts and figures Flyers no word on the kilos.

.............

Danke Advevo, thats very interesting that BMW has not confirmed the weight of this 2er race car. I guess we shall see.

[pikcachu]

Originally Posted by GoingTooFast

Yes. But BMW shouldn't go that route with the M2. Such a powerful 4 cyl. engine is not needed as long as BMW can lower the overall car weight in a meaningful way. Increasing the engine power only will make things more difficult than they are now...

Ok... so you complain about 6 cil on the M235 but you don't want a 4 cil for the M2?

then wth do you want? 5 cil

If you want 4 cil get a 228...

[BMoney]

Originally Posted by Greenkirby21

IMO the CLA45 4 cylinder is the least bland 4 cylinder engine I have heard! Lots of power and great sound for a 4 cylinder.

Would have to agree. I have a CLA45 with eurocharged tune and it's putting out 400 HP and 395 ft-lb of tq. Pretty impressive out of a 2 liter and sounds good as well with performance exhaust option. I'd say anything over 2200 RPMs and you're pretty much in the power band through redline. Definitely not bland in my opinion! To each their own though.

[GoingTooFast]

Originally Posted by pikcachu

Ok... so you complain about 6 cil on the M235 but you don't want a 4 cil for the M2?

I complain about everything that makes the car heavier without any meaningful purpose or advantage... turbocharged 6-cyl. engine being one of those things with the additional disadvantage of all the extra weight being placed toward the front axle.

Of course I would like to see a 4-cyl. engine in the upcoming M2 which would mean I could buy one, as my next car will have a turbocharged 4-cyl. engine for sure... what I'm saying is it doesn't need to have more than 300 hp.

Everytime you climb on the engine's power output scale you end up sacrificing lightness one way or another.

Stay below 300hp, stay below 1400 kg (EU weight) and I assure you BMW will have an ABSOLUTE winner... the first question is, at what price?!

The answer is, it all depends on BMW's engineering expertise... the second question is, are they capable of?!

The answer is, that's what I'm trying to figure out...

[GoingTooFast]

Originally Posted by pikcachu

Well I take "bland" any day before just plain ugly like the CLA rear..... front is pretty good but the back is just ridiculous

Maybe you like the CLA AMG Shooting brake rear... I think it looks better:

[leon1984]

Agreed on the first point, my first point is very very rarely does anyone produce an exciting handling 4WD platform. The new Golf R seems to be getting good reviews, but don't they all when they first come out.

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.

I first test drove an M235i Auto and found it dull. 0-60 in 4.8 seconds and I got out thinking "I couldn't care if I never drove that car again"... was pretty annoyed as I thought it ticked all the boxes.

I got persuaded to try the manual (in the M135 but same running gear) and was smitten, loved it and instantly ordered an M235 Manual. It isn't the 0-60 time that makes a car or engine exciting it is the delivery.

My old Cayman S was 5.5 to 60 and 3 times more exciting even in a straight line than an M135/235 or CLA for that matter. The engine is a masterpiece.

Originally Posted by GoingTooFast

AWD, RWD, FWD you can have exceptional good driver's cars on each of these guises... that is not the decisive factor... it's NOT the car's ability to drift that turns it into the best driver's car, that is a gross misconception cherished by some show-off motoring press!!!




0-62 mph in 4.6 seconds I wouldn't call it bland... which is something I cannot say about the M235i looks.