Z4M vs. 335i "feeling"

[O-cha]

Originally Posted by MVF4Rrider

Well, wrong. Engine torque isn't the same as total torque on the road. Torque applied to the road is what makes cars accelerate. Gearing is a torque multiplier, and that is what determines how much torque actually meets the road, which propels the car. With transmission gearing and final drive taken into consideration (tire circumference is negligable), the Z4 M puts down more torque to the ground than the 335i in all 6 gears (135i is different due to smaller tire circumference...the Z4 M bests the torque in 1st thru 4th, dead even in 5th, and slightly under in 6th). Gearing matters!!!

There's also vehicle weight, and the Z4 M is lighter, and makes more horsepower, mostly geared shorter, and revs 1,000 rpms longer. These are all things which aid acceleration. In addition, with the N54 you shift earlier and earlier with each next gear as holding the gears is a disadvantage with the severe power drop. With that, optium speed in gear isn't realized. With the Z4 M, the ideal shift points are at redline with the exception of 5th to 6th, where it's 500 revs sooner. It is impossible for the 335i to out accelerate a Z4 M. Period. However, tire grip is a factor and that point might favor the 335i due to BMWs poor tire choice for the Z4 M. But the Z4 M's LSD should help make up for it.

Stop being clouded by PEAK crank numbers, and quit taking magazine stats (which are climate corrected) as any kind of standardized measurement!!!!

Oh, and I've logged 4,000 miles in a 135i (which is faster than a 335i) and can tell you neither is as quick as the Z4 M. People are too tainted and preconditioned by looking at dyno graphs (which they can't translate to acceleration), and peak hp/torque figures, which are as much marketing as anything else.

Botomline line is the N54 feels quick due to it's turbo rush at low end, which is where most people spend on the rev counter. In order to go fast, you need rpms (more the better) and strong hp/torque on top and that's not N54 territory (torque charts prove this). You also need the right gear ratios to take advantage of everything, and mechanical grip. The only disappointing feature of the Z4 M is the tires, and that's easily rectified.

This is a doubled edged sword here I'm glad there is someone intelligent enough on this board to understand the difference between crank numbers wheel numbers, and actual wheel torque numbers through gearing, not so happy that said person is unable to comprehend that he's arguing with himself though .


The thread is about feeling, the 335 is quicker in this respect. You can trust me when I say I know exactly what you are talking about, a lot more so then you do. Here is a quick graph from a program I wrote in C to illustrate exactly what you are saying, I have been in the war against peak torque dyno readings and comparisons without respect to gearing for a long time now. Glad you could join us, next time though pick a target that doesn't actually know what he's talking about. And next time try and explain it in a way the lemmings can understand. For instance the height on this graph is directly proportional to the acceleration of the car, higher = faster.

Originally Posted by quickfast

You said...



Make up your mind.

One thing I hate more than people who don't know what they are talking about pretending like they do is people who take things out of context, that was a thread about canyon running you imbecile.

[MVF4Rrider]

That graph represents the total torque tables I made in Excel. In the Z4 M, you'll shift sooner but you're producing more torque at the point of the shift and at the point the rev counter lands after the gear change. It looks like in your graph you shifted the 335i at 7000 in all gears? Does your graph account for car weight? Of course my torque tables don't, but that should give the edge to the Z4 M even more so. I also think there should be at least a half-second difference between the two in the 1/4 mile, with the Z4 M winning of course. Ultimately these cars are further apart in true performance than mere tables and graphs represent. But the OP was concerned about the manufacturer's stated engine output as if that was a negative. It's a positive when you consider it's part of a far better balanced package--drivetrain, chassis, brakes, etc. Plus the S54 is a screamer!!! Add the shorter final gear and it's on a level performance with the new M3. These cars in power to weight aren't that far apart. They are a lot closer than the 335i is to the Z4 M.

[Dammmittt]

Originally Posted by O-cha

Now I'm interested, next time label your axes tho.

How did you come up with this chart and exactly what does higher=faster represent here?

[MVF4Rrider]

X = mph
Y = Total lb-ft as delivered to the ground

The dips are gear changes. So you can see in each gear the S54 is delivering more torque to the ground than a N54. You'd never convince 99% of N54 drivers that a motor with less crank torque can do that, but thanks to gearing it can. With a 3.91 final drive the pink line would be a lot taller in each gear (8%).

Questionable is where he determined his gear changes (probably at redline for both, which a torque table would prove isn't ideal for the N54). For the N54, you only want to redline the first 2 gears. After that there's too much total torque fall off to keep it revving that high, so you start stepping down the shift points. And with that you change gears sooner which limits the speed in that gear. In a word, that sucks.

I really think the N54 is the great BMW hoax of all time. It's a marketing smash hit, and mainly for people who just like to push hard to posted speed limits. Personally I think it thwarts driver involvement. Makes you lazy as hell. Not very BMW-like. But hey, at least they figured out a new use for the old E46 330i block. Wish I had a dollar for every 1Addicts idiot that thinks their 135i motor has the magnesium core aluminium block (which was a nice step forward for the cars fitted with it). They'll believe anything on that site as long as it's something for them to help worship what they think is the best BMW sports coupe of all time (which is clearly either the E30 M3 or E46 M3...I go back and forth).

[rcube]

335 is a better daily driver. Smooth, more power at the low end, easy to drive around in the city, not as loud. Less feel for speed, very stable... a GT car. You know basically a car that gets you from point A to B after the novelty wears off.

Z4M is not much of a daily driver... it kind of sucks at it. The power is up higher, you need to rev it higher than a 335. It is very raw. Sucks when driving slow. You feel the speed more with the Z4M. Basically it needs open road and curves... or the track.

I can fall asleep driving a 335... something that is not possible with the Z4M.

[karmasabish]

Originally Posted by rcube

I can fall asleep driving a 335... something that is not possible with the Z4M.

this line speaks it all honestly. You want your blood to flow - must have the M

[dngrCharlie]

I have a Z43.0si Roadster and a friend has a 335i convertible and, IMO, my cars feels faster and more fun to drive than her car does. I know she has more horses and her car is certainly more luxurious than my car but it's not nearly as much fun to drive. Plus you lose your trunk when the top comes down.

[Rick Hunter]

At this point, I think I'm leaning towards the Z4M. Oh... wait a minute... I already have one.

[O-cha]

Originally Posted by MVF4Rrider

it looks like in your graph you shifted the 335i at 7000 in all gears?'

First two gears, then it starts short shifting. I originally wrote the program to be a shift point calculator for cars with power roll off, but it was all the same data entry so I expanded it into the best possible bench racing program.

Originally Posted by MVF4Rrider

Does your graph account for car weight? Of course my torque tables don't, but that should give the edge to the Z4 M even more so.

That graph doesn't but if I put in weights it would by calculating a % weight difference and giving that % advantage to the other car. Since we are talking about wheel torque figures it can literally be directly applied to the values.

Originally Posted by MVF4Rrider

In the Z4 M, you'll shift sooner but you're producing more torque at the point of the shift and at the point the rev counter lands after the gear change.

Actually no, At no point what-so-ever should you short shift the z4m, you should redline it in every gear including 5th.

Originally Posted by MVF4Rrider

I also think there should be at least a half-second difference between the two in the 1/4 mile, with the Z4 M winning of course.

There is less then a tenth difference between the two cars in the quarter mile, if you think the Z4 m runs 13 second quarter miles you are nuts.

Originally Posted by Dammmittt

Now I'm interested, next time label your axes tho.

How did you come up with this chart and exactly what does higher=faster represent here?

Its wheel torque so it's literally acceleration power output. Higher then number, higher the acceleration. You will see why the 335 feels faster because in the low RPM (very early in the graph) it absolutely rapes the M in acceleration and holds for quite some time. Vs the M where it has to build and build and by then you dont even notice it.

Originally Posted by MVF4Rrider

I really think the N54 is the great BMW hoax of all time. It's a marketing smash hit, and mainly for people who just like to push hard to posted speed limits.

I disagree with you, it's quite a good engine for a commuter car, it's not for the track or racing though besides the fact it's so easily tunable. But you show me another 330 (yes it IS 330 HP) motor then can easily get 30mpg on the highway, they don't exist, not by a long shot, and not one that has 350 pounds of torque especially.

[Dammmittt]

Originally Posted by O-cha

Its wheel torque so it's literally acceleration power output. Higher then number, higher the acceleration. You will see why the 335 feels faster because in the low RPM (very early in the graph) it absolutely rapes the M in acceleration and holds for quite some time. Vs the M where it has to build and build and by then you dont even notice it.

No offense, but if you're only using wheel torque as a basis for your acceleration, you're an idiot.

[Nate2046]

Originally Posted by O-cha

I disagree with you, it's quite a good engine for a commuter car, it's not for the track or racing though besides the fact it's so easily tunable. But you show me another 330 (yes it IS 330 HP) motor then can easily get 30mpg on the highway, they don't exist, not by a long shot, and not one that has 350 pounds of torque especially.

Yay What do I win???

335i;
http://www.edmunds.com/used/2007/bmw...245/specs.html
C6;
http://www.edmunds.com/used/2007/che...682/specs.html

[epbrown]

Originally Posted by O-cha

But you show me another 330 (yes it IS 330 HP) motor then can easily get 30mpg on the highway, they don't exist, not by a long shot, and not one that has 350 pounds of torque especially.

Don't the current Corvette and 997 do that?

[O-cha]

Originally Posted by Nate2046

Yay What do I win???

335i;
http://www.edmunds.com/used/2007/bmw...245/specs.html
C6;
http://www.edmunds.com/used/2007/che...682/specs.html

Originally Posted by epbrown

Don't the current Corvette and 997 do that?

I'm talking about real life, not EPA, 335 really will do 30mpg easily. I wish you luck doing that in a c6.

Originally Posted by Dammmittt

No offense, but if you're only using wheel torque as a basis for your acceleration, you're an idiot.

Full offense meant here, if you call someone an idiot without understanding what they are talking about, then it is, in fact, you who is the idiot.


Wheel torque is acceleration, period, there is no debating this what so ever, the values on that graph ARE acceleration. You have no comprehension of this so why don't you refrain from calling people idiots until you do.

[Nate2046]

Originally Posted by O-cha

I'm talking about real life, not EPA, 335 really will do 30mpg easily. I wish you luck doing that in a c6.

You couldn't be more wrong if you tried. I posted the link with the EPA numbers showing identical highway numbers and my experience with LSx motors on the highway has been easy 30+ numbers. So I don't need your luck thanks, again what do I win????

[O-cha]

Originally Posted by Nate2046

You couldn't be more wrong if you tried.

C6 gets -10mpg on the highway, I tried and succeeded.

I highly doubt you're getting 30mpg highway at 80mph in a c6.

[Nate2046]

Originally Posted by O-cha

C6 gets -10mpg on the highway, I tried and succeeded.

Fair enough!

[MVF4Rrider]

Originally Posted by O-cha

Actually no, At no point what-so-ever should you short shift the z4m, you should redline it in every gear including 5th.

That's not what I'm saying. I'm well aware you should redline a Z4 M before shifting in all but 5th gear. In that gear you need to shift at 7500 as at 8000 it's putting less torque on the road than is available in 6th. My point about shifting sooner is that the Z4 M will reach it's maximum speed in each gear before the 335i; therefore shifts sooner (I believe that only applies to the first four gears--my tables are at work and I'm not).

Originally Posted by O-cha

I disagree with you, it's quite a good engine for a commuter car, it's not for the track or racing though besides the fact it's so easily tunable. But you show me another 330 (yes it IS 330 HP) motor then can easily get 30mpg on the highway, they don't exist, not by a long shot, and not one that has 350 pounds of torque especially.

Sure I'll give you that--it's a fine engine for a sporty commuter car (although I'd prefer my E90 DD to have a much smaller engine (2 liter) capable of far better economy), but too many think it's a performance engine. Tunable? That's subjective. You can increase peak numbers measureably but it changes the curve dramatically and the fall off in power in the last 2000 rpms is drastic. Why, because the motor can't take it and boost has to be backed off quite a lot to keep it from melting. A huge rise in peak power won't necessarily translate to too much improvement in acceleration/terminal velocity across the whole rpm range and gears, for this motor (N54) due to limitations. It needs more rpms for that and power curves which aren't headed due south. And the motor stock only produces exactly 282 hp at the wheels, for sure not 330. Here again, people make assumptions based on the thought (not fact) that BMW underrates their power outputs. And I think we've already well established crank numbers don't complete the story. Swedish company below is the most consistent I've ever seen in plotting power car to car. I use their output as a standard in which to make comparisons. Of course there's always the Euro/US spec differences to work around.

http://www.rri.se/popup/performanceg...p?ChartsID=647

[1stKnight]

I sold my E92 335i 2 months ago and bought a Z4 M Roadster.

Firstly, stock for stock, the 335i is 'easier' to overtake in as the 400Nm of torque ensures that compared to the Z4M, it needs less work to build up the speed; much like comparing a diesel to a petrol in some ways. And similarly, the 'entertainment' factor favours the ///M as a result.

In terms of sheer power and speed, the Z4M is the faster car, albeit slightly. It does out-accelerate the 335i but, again, it is - imo - a trickier beast to manage and the 335i is 'easier' to launch. But get it right and hit the Z4M's sweet spot and it delivers. In terms of midrange punch, the twin turbo 335i 'feels' faster much like a more torquey diesel 'feels' faster than a petrol. (335i vs 335d) But race from A-B and the ///M is faster overall.

On a pre-determined short, twisty course I have beaten my 335i times comfortably - this is due to the Z4M being slightly faster and handling far better.
I added an SSTT to my 335i and with it installed, it matches the Z4M for sheer pace in all respects but still wouldn't handle as well, obviously.

From experience, the 335i I owned for 2 years is a very capable car but not nearly as focussed in stock form as a Z4M, nor is it quite as fast in standard form.

[O-cha]

Originally Posted by MVF4Rrider

That's not what I'm saying. I'm well aware you should redline a Z4 M before shifting in all but 5th gear. In that gear you need to shift at 7500 as at 8000 it's putting less torque on the road than is available in 6th. My point about shifting sooner is that the Z4 M will reach it's maximum speed in each gear before the 335i; therefore shifts sooner (I believe that only applies to the first four gears--my tables are at work and I'm not).

No not really, they are geared to reach similar terminal speeds (they may differ by a couple MPH) in each gear. You must be comparing to the 335 auto.


Also, Shifting at 7500 would be a mistake.

Raw data:

153.9 700.9 7492 5
154 700.5 7496 5
154.1 700 7501 5
154.2 699.5 7506 5
154.3 699 7511 5
154.4 698.6 7516 5
//
163.4 656.4 7954 5
163.5 655.9 7959 5
163.6 655.4 7964 5
163.7 654.9 7969 5
163.8 654.5 7974 5
163.9 654.1 7978 5
164 653.5 6786 6
164.1 653.2 6790 6
164.2 652.9 6794 6
164.3 652.5 6798 6
164.4 652.2 6802 6
164.5 651.9 6806 6

[karmasabish]

Originally Posted by O-cha

No not really, they are geared to reach similar terminal speeds (they may differ by a couple MPH) in each gear. You must be comparing to the 335 auto.


Also, Shifting at 7500 would be a mistake.

Raw data:

153.9 700.9 7492 5
154 700.5 7496 5
154.1 700 7501 5
154.2 699.5 7506 5
154.3 699 7511 5
154.4 698.6 7516 5
//
163.4 656.4 7954 5
163.5 655.9 7959 5
163.6 655.4 7964 5
163.7 654.9 7969 5
163.8 654.5 7974 5
163.9 654.1 7978 5
164 653.5 6786 6
164.1 653.2 6790 6
164.2 652.9 6794 6
164.3 652.5 6798 6
164.4 652.2 6802 6
164.5 651.9 6806 6

why do you continue to post numbers without any headings?! lol you're like a half step away from being credible

[O-cha]

Originally Posted by karmasabish

why do you continue to post numbers without any headings?! lol you're like a half step away from being credible

If you were able to understand them with headings you would know what each was without them so I didn't bother. But since you said something, it's MPH wheel torque RPM and gear, in that order.

[O-cha]

Originally Posted by karmasabish

why do you continue to post numbers without any headings?! lol you're like a half step away from being credible

I make it really easy to understand:

Where the line intersects is where you shift. Since it's delineated via MPH the location of the next gear on the chart along the X axis is where you would be if you shifted from the lower gear and vise versa.

In simple terms, don't shift until the lines intersect, intersecting lines mean the torque in the next gear is higher then what you have in your current gear. But that doesn't happen with this car, ever.