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      09-13-2013, 08:11 AM   #1
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I don't have a back ground in these sorts of things, but I believe the 1M had an overboost function that gave more torque for brief periods of time. Does anyone think this will be in place with the new M3/M4, and could it possibly be around 450 tq if baseline is about 400?
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      09-13-2013, 09:30 AM   #2
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Quote:
Originally Posted by RMB View Post
I don't have a back ground in these sorts of things, but I believe the 1M had an overboost function that gave more torque for brief periods of time. Does anyone think this will be in place with the new M3/M4, and could it possibly be around 450 tq if baseline is about 400?
I can't see why not.

It works fine with the 1M.

But we all know torque means nothing

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      09-13-2013, 10:17 AM   #3
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I definitely like the feel of an engine with a lot of torque. I think that is one of the things that made me enjoy my supercharged S4 so much. I really look forward to this new FI engine in the M3/M4.
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      09-13-2013, 11:13 AM   #4
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I would think if the M engineers built a new engine specifically for this car (as opposed to just tuning one from the normal 1 and 3 series), the overboost would seem kind of gimmicky.

It should have plenty of torque out of the box without the need for overboost.
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      09-13-2013, 11:53 AM   #5
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Quote:
Originally Posted by kyleb350 View Post
I would think if the M engineers built a new engine specifically for this car (as opposed to just tuning one from the normal 1 and 3 series), the overboost would seem kind of gimmicky.

It should have plenty of torque out of the box without the need for overboost.
Yeah, but I am confused then. Porsche is very hardcore as a performance company, and the 911 turbo and 911 turbo S are both beasts. They come with an overboost function that enhances torque and that doesn't seem gimmicky. Overboost seems to be an aspect of some modern performance turbo engines, so it would seem that it would come that way with the M3/4.
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      09-13-2013, 01:32 PM   #6
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Quote:
Originally Posted by RMB View Post
Yeah, but I am confused then. Porsche is very hardcore as a performance company, and the 911 turbo and 911 turbo S are both beasts. They come with an overboost function that enhances torque and that doesn't seem gimmicky. Overboost seems to be an aspect of some modern performance turbo engines, so it would seem that it would come that way with the M3/4.
I agree. The issue is additional boost can be applied for a limited amount of time without having to upgrade all the engine systems to handle it. Why not have it!
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      09-13-2013, 02:42 PM   #7
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Originally Posted by GregW / Oregon View Post
I agree. The issue is additional boost can be applied for a limited amount of time without having to upgrade all the engine systems to handle it. Why not have it!
That's what I was thinking too. I agree with people in that if you buy an M it should not be watered down, but a true M. But IMHO I think the over boost aspect of a turbo engine is just more icing on the cake.

Now, if it comes with 395 lb/ft of torque (pure speculation), what do people think over boost would likely be at?

Last edited by RMB; 09-13-2013 at 02:44 PM.. Reason: another thought
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      09-13-2013, 05:46 PM   #8
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Quote:
Originally Posted by RMB View Post
That's what I was thinking too. I agree with people in that if you buy an M it should not be watered down, but a true M. But IMHO I think the over boost aspect of a turbo engine is just more icing on the cake.

Now, if it comes with 395 lb/ft of torque (pure speculation), what do people think over boost would likely be at?
Maybe around 440 lb/ft.
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      09-13-2013, 08:31 PM   #9
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I love the overboost on my iS. But, I'll gladly trade you 100HP for it. Just saying...
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      09-13-2013, 08:39 PM   #10
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yeah didn't the iS have it first?
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      09-14-2013, 02:24 AM   #11
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Quote:
Originally Posted by Robin_NL View Post
But we all know torque means nothing
I'll bite...

But before I continue let's be clear: Peak engine crank torque figures to be specific are pretty well meaningless. Obviously if one knows an entire torque curve the entire hp curve can be simply calculated.

Of course you realize that although such overboost features do not produce any additional peak hp they do provides additional power at lower rpm. It is the increase in power that matters. However, if one could choose additional torque and no addition in peak hp or an increase in peak hp which do you believe would offer more performance improvement (of course assuming each hypothetical vehicle is driven aggressively, i.e. for extracting maximum possible performance)?
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Last edited by swamp2; 09-14-2013 at 03:23 AM..
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      09-14-2013, 04:21 AM   #12
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Hmmm over boost function would be cool. ONLY if the car came with at least 450 HP and over boost would bump that +20 or so for whatever time they specify. I wouldn't want to see over boost function used as an excuse to give us an under-powered car. 400 HP would make me less than thrilled.
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      09-14-2013, 10:53 AM   #13
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Quote:
Originally Posted by swamp2 View Post
I'll bite...

But before I continue let's be clear: Peak engine crank torque figures to be specific are pretty well meaningless. Obviously if one knows an entire torque curve the entire hp curve can be simply calculated.

Of course you realize that although such overboost features do not produce any additional peak hp they do provides additional power at lower rpm. It is the increase in power that matters. However, if one could choose additional torque and no addition in peak hp or an increase in peak hp which do you believe would offer more performance improvement (of course assuming each hypothetical vehicle is driven aggressively, i.e. for extracting maximum possible performance)?
Well according to BMW it's an overboost from 450 to 500Nm for the 1M for 10 seconds or so and Nm (Newtonmeter) means torque in my book

So if I say 'torque' I'm wrong because you already explained it's hp.
But that would mean BMW is advertising wrong or what?




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      09-15-2013, 02:33 AM   #14
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      09-15-2013, 02:49 AM   #15
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Quote:
Originally Posted by Robin_NL View Post
Well according to BMW it's an overboost from 450 to 500Nm for the 1M for 10 seconds or so and Nm (Newtonmeter) means torque in my book

So if I say 'torque' I'm wrong because you already explained it's hp.
But that would mean BMW is advertising wrong or what?
Do you also believe the BMW nonsense that a 50-50 weight distribution is ideal for the "ultimate driving machine"?

Do you also believe BMW M is being honest and consistent when they have always focused on an M cars output (in hp, of course) and now with the switch to turbos they shift the discussion to significantly emphasize torque? This is called marketing, emphasize what you have, this is what turbo engines do, it is their nature. We as consumers should simply understand the details of what we are being sold and how we are being marketed to.

Again there is nothing wrong with more power (albeit even if temporarily) at mid rpms (i.e. not more peak power). It's just that more peak power is substantially more important.
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      09-15-2013, 04:59 AM   #16
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Swamp, thanks for your fine explanations ! Always good stories !

Must say I do like the torque, it`s addictive IMO, off course for daily driving very nice indeed.

The overboost is like good-better -best..... Just amazing the feel....

Now for the M4 I have no doubt, it will have more than sufficient HP and Nm and probably overboost function like the 1M , the weight is what matters most for me, since the car has grown in size yet again.
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      09-15-2013, 11:15 AM   #17
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Quote:
Originally Posted by Romo View Post
Swamp, thanks for your fine explanations ! Always good stories !

Must say I do like the torque, it`s addictive IMO, off course for daily driving very nice indeed.

The overboost is like good-better -best..... Just amazing the feel....

Now for the M4 I have no doubt, it will have more than sufficient HP and Nm and probably overboost function like the 1M , the weight is what matters most for me, since the car has grown in size yet again.
+1 and well said!

On another note, I would like to point out an observation of some 1M owners who track their cars frequently or who race in competitions, some of them are not huge fans of the overboost function (in those conditions) due to the nature of the system activated totally under the control of ECU and therefore quite unpredictable, especially when you are cornering at the limit of adherence. That's exactly when you might do without that extra wave of torque hitting the rear.

I like it a lot, since it obviously works perfectly under road/street driving conditions. It is like finding another piece of chocalate when you thought that the previous was the last
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      09-15-2013, 11:25 AM   #18
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Quote:
Originally Posted by pkim1079 View Post
yeah didn't the iS have it first?
Z435is came first and 335is later (and only in US market) followed with 1M. All have the same N54T engine but Z4 and 1M have higher output than the 3series. 1M also enjoys a different map than Z4 but I might be remembering that wrong, I just recall slightly different dyno charts of two engines from somewhere. Maybe whatever difference it is, it was necessary due to obligatory DCT in Z4 vs. obligatory 6 speed manual in 1M.
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Last edited by ozinaldo; 09-15-2013 at 08:28 PM..
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      09-15-2013, 01:12 PM   #19
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Quote:
Originally Posted by swamp2 View Post
Do you also believe the BMW nonsense that a 50-50 weight distribution is ideal for the "ultimate driving machine"?

Do you also believe BMW M is being honest and consistent when they have always focused on an M cars output (in hp, of course) and now with the switch to turbos they shift the discussion to significantly emphasize torque? This is called marketing, emphasize what you have, this is what turbo engines do, it is their nature. We as consumers should simply understand the details of what we are being sold and how we are being marketed to.

Again there is nothing wrong with more power (albeit even if temporarily) at mid rpms (i.e. not more peak power). It's just that more peak power is substantially more important.

Exactly...
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      09-15-2013, 03:28 PM   #20
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Quote:
Originally Posted by swamp2 View Post
Do you also believe the BMW nonsense that a 50-50 weight distribution is ideal for the "ultimate driving machine"?

Do you also believe BMW M is being honest and consistent when they have always focused on an M cars output (in hp, of course) and now with the switch to turbos they shift the discussion to significantly emphasize torque? This is called marketing, emphasize what you have, this is what turbo engines do, it is their nature. We as consumers should simply understand the details of what we are being sold and how we are being marketed to.

Again there is nothing wrong with more power (albeit even if temporarily) at mid rpms (i.e. not more peak power). It's just that more peak power is substantially more important.
albeit even if temporarily...that made me think; isn't all power temporary? I mean whatever number we pick, isn't it at a given rpm, including the peak power?

Questions:

1) How do we benefit from "peak" power frequent enough in real world driving, since it is reached at the top end of the revs in good NA engines like the S65?
2) Why exactly peak power is "substantially more important" unless of course we live around Nurburgring or our daily commute pass to/from unlimited sections of autobahn?...which would be great by the way!
3) How exactly an engine (N54T) which produces not only more torque (around 60% more) but also more hp from idle to around 6250 rpm vs. a magnificiant NA engine, and only after that it starts falling back (vs. the other engine, the S65 of course) for the last 750 rpms left, can be performing less in a variety of situations in real world driving where you are supposed to be driving around different rpms and not at a single rpm, especially not around top of the rev? This even before we also take into consideration weight and power to weight factors.
4) How do you explain the fact that despite being more tricky to launch effectively, a 1M manages to stay (slightly) ahead of a manual M3 untill the end of its third gear (around 180 km/h) and starts falling behind only after around 200+ km/h, according to people who owned or still own both, are these people simply lying or don't know what they talk about? Or, is it maybe one of them is way underrated and/or the other overrated, who knows, and simply taking those BMW advertised hp/tq numbers as a base for sound calculation maybe is the very reason of reaching misleading conclusions?
5) Did you ever drive a 1M or a 335is or a Z435is, I mean long enough and not as a passenger, to understand their driving/delivery characteristics, preferably a 1M, since it also has the parts and bits that makes it more comparable/similar to your car?

I enjoy your posts and strong logic and knowledge behind them, I really do and am not here to contest you, also am a fan of S65 and M3, could be my choice if it would be smaller in size and with less weight. It is plain and simple: the more I read from you the more I started getting curious; how do you answer these questions to yourself, I am very curious to hear. Do you say that what we experience out there all day is an illusion?

Thanks in advance.
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Last edited by ozinaldo; 09-15-2013 at 08:52 PM..
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      09-15-2013, 11:02 PM   #21
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You go to the track.

Its meant for track type of driving, go to redline shift, repeat.

There is actually 2250 more rpms to go.

It has 2 more cylinders.

I also drive a 135 with dct daily (gfs car) and there is a lack of throttle response and turbo lag. Even though torque is down low, you still have to downshift and hammer it just like in any other car if you want to maximize acceleration from a roll.

Its more the delivery of the power and not the peak numbers i would say - as in, power keeps coming all the way to redline and torque is constant throughout the entire rev range rather than having a spike and then a drop off.
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      09-15-2013, 11:49 PM   #22
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I don't understand why the car industry doesn't simply add a new number, "area under the torque curve"...

You'd think BMW of all companies would have pushed something like that back in 2007 -- they could have ridden that number (and dominance vs. the competition) for many years with the 335i!

And it would prevent a lot of HP vs. torque arguments...
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