Any 135i to M3 crossovers?

[bruce.augenstein@comcast.]

Originally Posted by graider

no. lol

i have no issue doing that on the highway at all. in fact downshift and punch it allow you to go much faster and merging in/out is a breeze.

i mean if you just want to go faster than someone to merge in/out, might as well buy a full auto like amg. there is no point to buy an mt but not using it the way it should be.

So, you wouldn't like your M3 as much if it had more punch at low and middling rpm?

Really?

[graider]

Originally Posted by bruce.augenstein@comcast.

So, you wouldn't like your M3 as much if it had more punch at low and middling rpm?

Really?

no. I like the sensation of hearing the engine scream to life. put it this way. when you are banging a chick, you want her to scream up there, not mumbling like a low reeving diesel/turbo.

m engine does has torque, it just you have to bang her hard to get it.

[bruce.augenstein@comcast.]

Originally Posted by graider

no. I like the sensation of hearing the engine scream to life. put it this way. when you are banging a chick, you want her to scream up there, not mumbling like a low reeving diesel/turbo.

...and what a lovely specimen of humanity you are.

On the technical side, I believe you think adding low end torque will somehow subtract from the top end, which is ridiculous.

Originally Posted by graider

m engine does has torque, it just you have to bang her hard to get it.

No, it's a little weak on torque. What it does is make a bunch of horsepower. You're parading your ignorance.

[graider]

Originally Posted by bruce.augenstein@comcast.

...and what a lovely specimen of humanity you are.

On the technical side, I believe you think adding low end torque will somehow subtract from the top end, which is ridiculous.



No, it's a little weak on torque. What it does is make a bunch of horsepower. You're parading your ignorance.

Read my posts again. i never say adding low end torque is a bad thing. I'm just saying the m engine has enough useable torque and it is fine the way it is. Looks like you think you have better idea than thousand of m engineers. There is a reason why they went with a 4L instead of 5, 6, or even 7L.

if they go with 5-6L with 7000rpm, then everyone will start bashing why the redline is so low, it is just a big engine, no different than all the car out there, etc....etc

If you love torque so much, then supercharge/turbo charge it. or go with a big engine with low rev or a diesel. ton of torque for you. but again that is not the point of a small displacement high reving engine.

different car fits different folks. if you are into torque, turbo car or z06 are for you. if you are into high rev and smooth engine, then m is for you. simple as that.

[adc]

Originally Posted by bruce.augenstein@comcast.

On the technical side, I believe you think adding low end torque will somehow subtract from the top end, which is ridiculous.

Is it truly ridiculous?

My impression was that torque is a factor of several things, the most important being cylinder capacity and the length of the stroke. So for an engine of a given capacity, if you increase the stroke you also increase the torque - but increasing the stroke effectively limits the rev limit, which ultimately limits the top end HP.

I'm not a mechanical engineer so I could be way off the mark.


All that aside, I found that the E9x M3 has sufficient torque to easily waft through commuter traffic, significantly more so than the E46 M3. It's sufficient for my taste.

[graider]

Originally Posted by adc

Is it truly ridiculous?

My impression was that torque is a factor of several things, the most important being cylinder capacity and the length of the stroke. So for an engine of a given capacity, if you increase the stroke you also increase the torque - but increasing the stroke effectively limits the rev limit, which ultimately limits the top end HP.

I'm not a mechanical engineer so I could be way off the mark.


All that aside, I found that the E9x M3 has sufficient torque to easily waft through commuter traffic, significantly more so than the E46 M3. It's sufficient for my taste.

exactly. even my lowly e46 m3 has more than enough torque for daily use. it is not slow off the line by any mean even for today standard.

[bruce.augenstein@comcast.]

Originally Posted by graider

Read my posts again. i never say adding low end torque is a bad thing. I'm just saying the m engine has enough useable torque and it is fine the way it is. Looks like you think you have better idea than thousand of m engineers. There is a reason why they went with a 4L instead of 5, 6, or even 7L.

if they go with 5-6L with 7000rpm, then everyone will start bashing why the redline is so low, it is just a big engine, no different than all the car out there, etc....etc

If you love torque so much, then supercharge/turbo charge it. or go with a big engine with low rev or a diesel. ton of torque for you. but again that is not the point of a small displacement high reving engine.

different car fits different folks. if you are into torque, turbo car or z06 are for you. if you are into high rev and smooth engine, then m is for you. simple as that.

I'm not particularly into torque as opposed to horsepower, but put it this way:

If the current M3 made the same torque per liter as the last M3, it would peak at 335 pound feet instead of 295 pound feet, "simple as that". And no, it wouldn't have to sacrifice that terrific top end rush.

I personally thought the 2004 M3 that graced our garage had a less steep torque curve at the low end, and didn't feel as lazy as the current model does down in that range - but I admit that part of that may be because of the extra 200 pounds or so they piled onto the new one.

I like turbos, too, but your either/or statement above is just so much crap

[michaeldorian]

Originally Posted by bruce.augenstein@comcast.

I'm not particularly into torque as opposed to horsepower, but put it this way:

If the current M3 made the same torque per liter as the last M3, it would peak at 335 pound feet instead of 295 pound feet, "simple as that". And no, it wouldn't have to sacrifice that terrific top end rush.

I personally thought the 2004 M3 that graced our garage had a less steep torque curve at the low end, and didn't feel as lazy as the current model does down in that range - but I admit that part of that may be because of the extra 200 pounds or so they piled onto the new one.

I like turbos, too, but your either/or statement above is just so much crap

Exactly. This is the problem with the current engine design. I do believe it's due to the extra 200LBS though. Add a passenger and it's feels even worse. I think a "CSL" version of this car would be darn near perfect. I do believe that the M engineers, if tasked with the problem, can figure out a way to reduce ~200 lbs without sacrificing the comfort of that car in any way. The car just feels a bit compromised compared to the out going model. It's trying to hard to be everything to everybody. Darn product managers.

[bruce.augenstein@comcast.]

Originally Posted by adc

Is it truly ridiculous?

My impression was that torque is a factor of several things, the most important being cylinder capacity and the length of the stroke. So for an engine of a given capacity, if you increase the stroke you also increase the torque - but increasing the stroke effectively limits the rev limit, which ultimately limits the top end HP.

I'm not a mechanical engineer so I could be way off the mark.

As I pointed out just above, if the current model made the same torque per liter as the E46, then it would make 40 more foot pounds than it now does - and we most probably wouldn't be having this conversation.

By the way, all other things being equal, cylinder capacity is close to immaterial, assumimg you meant the capacity of a single cylinder (i.e. - 500cc as opposed to four liters).

Stroke also has little to do with overall torque - period. I know a lot of people think that it does, but it's just not true. Do the math, please. At a given bmep, the extra square inches of piston crown effectively counterract the greater leverage of a longer moment arm - assuming same displacement, of course.

Originally Posted by adc

All that aside, I found that the E9x M3 has sufficient torque to easily waft through commuter traffic, significantly more so than the E46 M3. It's sufficient for my taste.

Point made - but as we've already learned, some folks think they have more than enough low end in the M3, some, like yourself, are satisfied - and some just think it's too lazy around town, and don't like having to use the left hand side of the tach* to get their jollies.

Personally, I love the new engine, but also wish it had more low end. That's primarily because the new car is so damned big and heavy, though.

Current owners have every right to love their cars, but I'm saddled with M3 baggage. Because of the size and weight issues, I liked our E36 best of all. Better than our E46 and better than the new one.

Edit: PS - Pardon me. Meant right hand side of the tach above.

[adc]

Originally Posted by bruce.augenstein@comcast.

If the current M3 made the same torque per liter as the last M3, it would peak at 335 pound feet instead of 295 pound feet, "simple as that". And no, it wouldn't have to sacrifice that terrific top end rush.

I personally thought the 2004 M3 that graced our garage had a less steep torque curve at the low end, and didn't feel as lazy as the current model does down in that range

My impression of the current vs. previous M3 torque curves is not necessarily the same as yours. I don't remember what the old one did between 1000-2000 RPM, which is the only range where I've truly found the new one wanting (especially in the higher gears).

But everywhere else, my impression is that, quite contrary to yours, the new one has a flatter torque curve and the engine feels more athletic. I would very much like to see in-gear acceleration times for the 2 generations, which I feel would support my impression.

If you also look at the max-torque-to-weight ratios for the 2 cars with a driver on board, the new car's is about 10% better. But what about the torque per liter number? I think BMW has sacrificed some peak torque in an attempt to spread it more evenly - and succeeded. Again, IMO.

[adc]

Originally Posted by bruce.augenstein@comcast.

By the way, all other things being equal, cylinder capacity is close to immaterial, assumimg you meant the capacity of a single cylinder (i.e. - 500cc as opposed to four liters).

I actually meant total capacity and I'm at a loss understanding why you don't think it matters. There is no way a single-cylinder 500cc engine would make 295 lbs of torque, is it?

Not trying to start a flame war, just trying to understand.

Stroke also has little to do with overall torque - period. I know a lot of people think that it does, but it's just not true. Do the math, please. At a given bmep, the extra square inches of piston crown effectively counterract the greater leverage of a longer moment arm - assuming same displacement, of course.

Not sure I understand what increased surface has to do with torque. Would you mind elaborating?

[330CIZHP]

Originally Posted by bruce.augenstein@comcast.

I'm not particularly into torque as opposed to horsepower, but put it this way:

If the current M3 made the same torque per liter as the last M3, it would peak at 335 pound feet instead of 295 pound feet, "simple as that". And no, it wouldn't have to sacrifice that terrific top end rush.

I personally thought the 2004 M3 that graced our garage had a less steep torque curve at the low end, and didn't feel as lazy as the current model does down in that range - but I admit that part of that may be because of the extra 200 pounds or so they piled onto the new one.

I like turbos, too, but your either/or statement above is just so much crap

Rather than bashing him, although I have always understood that mathematically speaking, graph area under the curve is what matters the most and not peak numbers, but just for giggles, why don't you give some real world examples of which cars have immense high-rpm torque curves, rev up to 8400 - 8500 rpm and produce that much torque/liter down at a low ~3000 rpm?? just like you said, E90 M3 should have had 335 ft-lbs of torque assuming the E46 M3 made 260 ft-lbs from a 3.2 Liter engine (which is 84 ft-lbs/liter for the E92/E90). Give me ONE example of a high-revving car that produces 84 ft-lbs/liter at ANY rpm, let alone at a low 2000 - 3000 rpm. ONE! and I will stand corrected.

This has been a known fact in order to bring the peak torque down low and produce more usable torque in the low and midrange, you MUST sacrifice the top rpm torque curve, which would make it futile to have a redline. Technology using (VarioCAM, VANOS, VVT etc.) can somewhat make it better, but it will almost never eliminate that in N/A high-revving engines.

E46 M3 peaked at 5200 rpm in terms of torque 80% of which is available only at 1800 rpm while the E90/E92 peaks only at 3900 rpm. 90% of which is available only at 1800 rpm. See the difference there??? PEAKINESS! The E90/E92 is far less peaky than the E46 yet it has a much higher redline because it produces more usable torque at high rpms resulting in a higher redline. In other words, the E90/E92 has a far broader powerband than the E46 ever had due to the immensely wide area under the torque curve that is completely flat.

For example, in this dyno of an E46 M3 vs 335 vs E92 M3 done on the same day and sametime:

http://mmm.os.org.za/d/1799-1/DSC04302s.jpg

E92 M3: 360 WHP, 266 ft-lbs@3750 rpm 67 ft-lbs of wheel/torque/liter @3750 rpm
E92 335: 281 WHP, 286 ft-lbs@3700 rpm
European E46 M3 (343 HP, not 333 HP): 295 WHP, 238 ft-lbs@5000 rpm 74 ft-lbs of wheel torque/liter @ 5000 rpm

At 1800 - 3700 rpm, the E46 makes FAR less than the 266 ft-lbs of wheel torque E90 is making. I can guarantee on dynos, it would be no higher than 190 - 205 ft-lbs of wheel torque in the 1800 - 3700 rpm rev range. So low end and midrange wise, the E90 is far ahead of the E46. So again that begs the question, how did you come up with the 335 ft-lbs of torque required for the E92 M3 using the torque/liter of E46 M3 as a basis???

E92/E90 M3 is making 266 ft-lbs of wheel torque starting a at a low 2000 - 3000 rpm. That is more than your TL Type S produces at the CRANK PEAK while weighing an almost identical ballpark 3600 lbs weight figure. How do you live with your TL Type S then???

So according to your implications that M3 makes no torque, your TL Type S probably has a miserable existence especially if it is an auto slushbox that cannot even get out of its own way for the life of its driver.


Since the V8 is a derivative of the M5 V10 (producing 383 ft-lbs of torque from 5.0 Liter at a peaky ~6100 rpm), I am absolutely sure if M3 was not tuned for a broader torque curve, it could have easily produced 320 - 325 ft-lbs of peak torque at 6100 - 6500 rpm, but would have sacrificed a lot of torque down low making it a top end monster, but a total dog in everyday driving, which the M5 had gained reputation for.

Many of the stock dynos I have seen of North American E46 M3 show peak torque of 220 - 230 ft-lbs of wheel torque at around 5100 - 5500 rpm (assuming a 280 - 290 whp dyno) while the E90/E92 M3 with a much higher redline (8400 rpm vs 7900 rpm) dynos at 265 - 270 ft-lbs of wheel torque at a low 3500 - 3800 rpm (assuming around 350 - 360 wheel HP dyno).

At the end of the day, much rather cut with the theoratical bullsh*t and give some real world examples of ANY 4.0 - 4.2 Liter high-revving engine (atleast 8250 - 8400 rpm) that produces that much torque (335 ft-lbs).

I will begin here:

M3 4.0 Liter V8: 295 ft-lbs@3900 rpm (redline: 8400 rpm) 74 ft-lbs/liter
Audi FSI 4.2 Liter V8 (RS4): 317 ft-lbs@5500 rpm (redline: 8250 rpm) 75 ft-lbs/liter

Let's look at some other high revving engines:

Porsche Carrera GT: 5.7 Liter V10 435 ft-lbs@6100 rpm (redline:8500 rpm) 75 ft-lbs/liter
Ferrari F430: 4.3 Liter V10 490 V8 340 ft-lbs@5250 rpm (redline: 8500 rpm) 78 ft-lbs/liter
Lamborghini Gallardo 5.0 Liter V10 376 ft-lbs @ 4400 rpm (redline: 8500 rpm) 74 ft-lbs/liter
Aston Martin V8 Vantage 4.3 Liter V8 300 ft-lbs @ 5000 rpm (redline: 8000 rpm) 69 ft-lbs/liter
M5/M6 V19 : 4.0 Liter V10 383ft-lbs @ 6100 rpm (redline: 8250 rpm) 76 ft-lbs/liter

From these examples above, M3 produces a healthy foot-lbs of torque per liter comparable to most other high-revving engines, yet is able to attain the peak at a much lower rpm than any of these exotic examples here. The difference is that M3 sacrificed some top end torque to attain a much flatter torque curve with a much more usable midrange.

Like I mentioned, I would actually like to see some proof of a high-revving car that produce gobbs of torque down low yet have an immense high-revving capacity and top end torque (say, just like you said 84 ft-lbs/liter).


Now in the low-revving S5 model, the Audi FSI 4.2 Liter V8 makes 355 HP, but makes more torque than the R8 or the RS4 at 325 ft-lbs at guess what?? 6800 rpm! Does that make the S5 make more drivable in the city? Maybe? Does it have equal or more top end than the Audi R8 and RS4 variant of the 4.2 Liter V8??? HELL NO!!! Those two cars slaughter the S5 in an all-out race.

All in all, if M3 had produced more torque down low, it would have sacrificed a lot of high-rpm torque, which would have resulted in a much lower redline around 7800 - 7900 rpm.

BMW was shooting for a more aggressively tuned high-revving M car with a high redline, but without compromising on the low-end torque too much. Too bring the peak torque down low, it ended up producing a lower number for the peak torque, yet it produced it across an incredibly wide rev range. 90% of M3's 295 ft-lbs peak torque comes in at 1800 rpm and stays at 90% until 8300 rpm for a full 6500 rpm. A powerband of 6500 rpm is no ordinary feat.

[bruce.augenstein@comcast.]

Originally Posted by 330CIZHP

Rather than bashing him, why don't you give some real world examples of which cars have immense high-rpm torque curves, rev up to 8400 - 8500 rpm and produce that much torque/liter down at a low ~3000 rpm?? just like you said, E90 M3 should have had 335 ft-lbs of torque assuming the E46 M3 made 260 ft-lbs from a 3.2 Liter engine (which is 84 ft-lbs/liter for the E92/E90). Give me ONE example of a high-revving car that produces 84 ft-lbs/liter at ANY rpm, let alone at a low 2000 - 3000 rpm. ONE! and I will stand corrected

Uh - my last M3, as we've been discussing. You stand corrected. Oh, and the new Ferrari 4.5 V8 makes 88 pound feet per liter and revs to at least 9000 rpm.

And bashing? He said if I like low-end torque, get a turbo, etc., etc., and I said that's crap - because of course it is. The fact is that the only soft spot (other than abysmal fuel mileage) in an otherwise outstanding powerplant is that it's a little soft at low rpm, and a little shy on total torque. The other fact is that I have personally thrown more (and more eloquent) roses at this powerplant in this venue than you have.

Originally Posted by 330CIZHP

This has been a known fact in order to bring the peak torque down low and produce more usable torque in the low and midrange, you MUST sacrifice the top rpm torque curve, which would make it futile to have a redline. Technology using (VarioCAM, VANOS, VVT etc.) can somewhat make it better, but it will almost never eliminate that in N/A high-revving engines.

Have no idea what this means in relation to our discussion. We're talking about an engine that has a peak torque figure arriving at 3900 rpm and revs to 8400. What the hell is your point?

Originally Posted by 330CIZHP

E46 M3 peaked at 5200 rpm in terms of torque 80% of which is available only at 1800 rpm while the E90/E92 peaks only at 3900 rpm. 90% of which is available only at 1800 rpm. See the difference there??? PEAKINESS! The E90/E92 is far less peaky than the E46 yet it has a much higher redline because it produces more usable torque at high rpms resulting in a higher redline.

So, if I get your drift right (you're a little tricky to understand when you're off your meds), if the M3 made its 295 pound feet at 3900, but peaked at 335 pound feet at 5200, wouldn't it be a better overall engine? Look, the fact is the new one feels a little lazy around town, partly because of its weight.

Originally Posted by 330CIZHP

For example, in this dyno of an E46 M3 vs 335 vs E92 M3 done on the same day and sametime:

http://mmm.os.org.za/d/1799-1/DSC04302s.jpg

E92 M3: 360 WHP, 266 ft-lbs@3750 rpm 67 ft-lbs of wheel/torque/liter @3750 rpm
E92 335: 281 WHP, 286 ft-lbs@3700 rpm
European E46 M3 (343 HP, not 333 HP): 295 WHP, 238 ft-lbs@5000 rpm 74 ft-lbs of wheel torque/liter @ 5000 rpm

What I get out of this is that, as per quoted specs, the E46 makes more torque per liter than the new one. Right? I don't give a damn where it peaks. I feel the current model has a more noticeable transition when the tach moves past high noon.

Originally Posted by 330CIZHP

At 1800 - 3700 rpm, the E46 makes FAR less than the 266 ft-lbs of wheel torque E90 is making. I can guarantee on dynos, it would be no higher than 190 - 205 ft-lbs of wheel torque in the 1800 - 3700 rpm rev range. So low end and midrange wise, the E90 is far ahead of the E46. So again that begs the question, how did you come up with the 335 ft-lbs of torque required for the E92 M3 using the torque/liter of E46 M3 as a basis???

The E90 is far ahead of the E46 in every performance measurement, so what's your point? It makes more torque and more power, and revs a little higher. As to your question: 268 pound feet out of 3.2 liters equals 335 pound feet out of four liters at the same torque per liter number.

Originally Posted by 330CIZHP

E92/E90 M3 is making 266 ft-lbs of wheel torque starting a at a low 2000 - 3000 rpm. That is more than your TL Type S produces at the CRANK PEAK while weighing an almost identical ballpark 3600 lbs weight figure. How do you live with your TL Type S then???

So according to your implications that M3 makes no torque, your TL Type S probably has a miserable existence especially if it is an auto slushbox that cannot even get out of its own way for the life of its driver.

Not sure what brought this on, other than you being off your meds, of course. I got my Acura instead of a 335i, because I just couldn't stand the lack of posi plus runflats in the bimmer. I'd do the same thing again if whisked back to 2007 - although I must say I can't stand the current TL.

Originally Posted by 330CIZHP

Since the V8 is a derivative of the M5 V10 (producing 383 ft-lbs of torque from 5.0 Liter at a peaky ~6100 rpm), I am absolutely sure if M3 was not tuned for a broader torque curve, it could have easily produced 320 - 325 ft-lbs of peak torque at 6100 - 6500 rpm, but would have sacrificed a lot of torque down low making it a top end monster, but a total dog in everyday driving, which the M5 had gained reputation for.

Many of the stock dynos I have seen of North American E46 M3 show peak torque of 220 - 230 ft-lbs of wheel torque at around 5100 - 5500 rpm (assuming a 280 - 290 whp dyno) while the E90/E92 M3 with a much higher redline (8400 rpm vs 7900 rpm) dynos at 265 - 270 ft-lbs of wheel torque at a low 3500 - 3800 rpm (assuming around 350 - 360 wheel HP dyno).

At the end of the day, much rather cut with the theoratical bullsh*t and give some real world examples of ANY 4.0 - 4.2 Liter high-revving engine (atleast 8250 - 8400 rpm) that produces that much torque (335 ft-lbs).

I will begin here:

M3 4.0 Liter V8: 295 ft-lbs@3900 rpm (redline: 8400 rpm) 74 ft-lbs/liter
Audi FSI 4.2 Liter V8 (RS4): 317 ft-lbs@5500 rpm (redline: 8250 rpm) 75 ft-lbs/liter

Let's look at some other high revving engines:

Porsche Carrera GT: 5.7 Liter V10 435 ft-lbs@6100 rpm (redline:8500 rpm) 75 ft-lbs/liter
Ferrari F430: 4.3 Liter V10 490 V8 340 ft-lbs@5250 rpm (redline: 8500 rpm) 78 ft-lbs/liter
Lamborghini Gallardo 5.0 Liter V10 376 ft-lbs @ 4400 rpm (redline: 8500 rpm) 74 ft-lbs/liter
Aston Martin V8 Vantage 4.3 Liter V8 300 ft-lbs @ 5000 rpm (redline: 8000 rpm) 69 ft-lbs/liter
M5/M6 V19 : 4.0 Liter V10 383ft-lbs @ 6100 rpm (redline: 8250 rpm) 76 ft-lbs/liter

From these examples above, M3 produces a healthy foot-lbs of torque per liter comparable to most other high-revving engines, yet is able to attain the peak at a much lower rpm than any of these exotic examples here. The difference is that M3 sacrificed some top end torque to attain a much flatter torque curve with a much more usable midrange.

Like I mentioned, I would actually like to see some proof of a high-revving car that produce gobbs of torque down low yet have an immense high-revving capacity and top end torque (say, just like you said 84 ft-lbs/liter).

Our E46 didn't have that same sort of transitional softness that the new one has.

Originally Posted by 330CIZHP

Now in the low-revving S5 model, the Audi FSI 4.2 Liter V8 makes 355 HP, but makes more torque than the R8 or the RS4 at 325 ft-lbs at guess what?? 6800 rpm! Does that make the S5 make more drivable in the city? Maybe? Does it have equal or more top end than the Audi R8 and RS4 variant of the 4.2 Liter V8??? HELL NO!!! Those two cars slaughter the S5 in an all-out race.

All in all, if M3 had produced more torque down low, it would have sacrificed a lot of high-rpm torque, which would have resulted in a much lower redline around 7800 - 7900 rpm.

BMW was shooting for a more aggressively tuned high-revving M car with a high redline, but without compromising on the low-end torque too much. Too bring the peak torque down low, it ended up producing a lower number for the peak torque, yet it produced it across an incredibly wide rev range.

As mentioned, I have written glowing prose about this engine - but the fact is that quite a number of folks that I know personally and "know" through the Internet wish the M3 was a bit more responsive around town than it is. That's partly because it's gained weight (again), and partly because of engine tuning.

If you were back on your meds, even you might agree - but of course as a fanboy you feel that any intimation the E90 has a bit of a soft spot around town must be crushed.

Pretty much every owner I've talked to or conversed with says that the M3 doesn't come alive until you get to the right-hand side of the tach, and of course that's also been my experience. Feel free to continue your disagreement.

[bruce.augenstein@comcast.]

Originally Posted by adc

I actually meant total capacity and I'm at a loss understanding why you don't think it matters. There is no way a single-cylinder 500cc engine would make 295 lbs of torque, is it?

Not trying to start a flame war, just trying to understand.

Thought you meant individual cylinder capacity, as I mentioned directly in my note. Total capacity of course matters a bunch.

Originally Posted by adc

Not sure I understand what increased surface has to do with torque. Would you mind elaborating?

Take any given cylinder pressure - say 2000 psi. A piston with, say, 12 square inches of surface area will be subject to a downward force of 24,000 pounds. A piston with ten square inches will have 20,000 pounds. You get the idea. Of course, in order to maintain the same engine capacity, the stroke would be reduced in the engine with the larger pistons, so there is less of that total pressure converted to rotational force because you have less leverage due to the shorter moment arm.

The net is that long stroke vs short stroke engines don't have intrinsically differing torque peaks. It's just that if you design a long-stroke engine, you're doing that because you intend it to have a torque curve that peaks earlier and runs out earlier than the short stroke variant.

Think street engine vs race engine. The only race engines that are undersquare are those that are constrained to be that way by the class rules. Given free reign, a designer will go with big bore and short stroke since he or she needs to do that to turn up the big numbers - which is critical for horsepower, since torque numbers (per cc) are quite constrained. F1 engines, which turn up to 19000 rpm and make, what, 700 or 800 horsepower out of 2.5 liters? still don't make much over 100 foot pounds per liter. Street engines are trapped in the eighties or below per liter, unless they specifically tune intake and exhaust for a given rpm, which raises the peak but diminishes torque elsewhere.

[bruce.augenstein@comcast.]

Originally Posted by adc

My impression of the current vs. previous M3 torque curves is not necessarily the same as yours. I don't remember what the old one did between 1000-2000 RPM, which is the only range where I've truly found the new one wanting (especially in the higher gears).

But everywhere else, my impression is that, quite contrary to yours, the new one has a flatter torque curve and the engine feels more athletic. I would very much like to see in-gear acceleration times for the 2 generations, which I feel would support my impression.

If you also look at the max-torque-to-weight ratios for the 2 cars with a driver on board, the new car's is about 10% better. But what about the torque per liter number? I think BMW has sacrificed some peak torque in an attempt to spread it more evenly - and succeeded. Again, IMO.

The new one is better in every way than the E46, except of course for its size and weight which makes the car less fun to toss around. As I've previously documented, the low-end softness doesn't bother me personally, and in fact I didn't notice anything lacking until I specifically tested for it. The short gears and amazingly zingy powerplant let you drive through that with ease. I've also documented my admiration for that amazingly flat torque curve. Absolutely flatter than the E46.

[adc]

Originally Posted by bruce.augenstein@comcast.

Take any given cylinder pressure - say 2000 psi. A piston with, say, 12 square inches of surface area will be subject to a downward force of 24,000 pounds. A piston with ten square inches will have 20,000 pounds. You get the idea. Of course, in order to maintain the same engine capacity, the stroke would be reduced in the engine with the larger pistons, so there is less of that total pressure converted to rotational force because you have less leverage due to the shorter moment arm.

The net is that long stroke vs short stroke engines don't have intrinsically differing torque peaks. It's just that if you design a long-stroke engine, you're doing that because you intend it to have a torque curve that peaks earlier and runs out earlier than the short stroke variant.

Think street engine vs race engine. The only race engines that are undersquare are those that are constrained to be that way by the class rules. Given free reign, a designer will go with big bore and short stroke since he or she needs to do that to turn up the big numbers - which is critical for horsepower, since torque numbers (per cc) are quite constrained. F1 engines, which turn up to 19000 rpm and make, what, 700 or 800 horsepower out of 2.5 liters? still don't make much over 100 foot pounds per liter. Street engines are trapped in the eighties or below per liter, unless they specifically tune intake and exhaust for a given rpm, which raises the peak but diminishes torque elsewhere.

That makes sense, thank you for the clarification.

[330CIZHP]

Originally Posted by bruce.augenstein@comcast.

Uh - my last M3, as we've been discussing. You stand corrected. Oh, and the new Ferrari 4.5 V8 makes 88 pound feet per liter and revs to at least 9000 rpm.

The new Ferrari 458 is almost a race car tuned for completely top end power. In terms of being high-strung, I would compare it to the F360 rather than much less high-strung F430 since F360 modena made more ft-lbs/liter than the F430 closer to the claimed F458. If you remember anything about the Ferrari F360 Modena (or know anyone who owns a Ferrari F360), go and ask him/her. Just do a search on the dynos of a stock F360. The car produced 280 ft-lbs of torque from only a 3.6 Liter V8. That is an impressive 78 ft-lbs/liter. Yet, ask any F360 owner and they would tell you the car was an absolute dog below 5000 rpm. All of the torque was concentrated above 6000 rpm uptill 8500 rpm thanks to a huge surge in torque. It was a top end monster, but a complete nightmare to drive in everyday life. Clutch modulation is extremely difficult due to a light flywheel, heavy clutch and lack of low-end torque. You have to slip the clutch like crazy to get it going. If the F458 engine is anything like the F360 where the engine was far more high strung than the Ferrari F430, it would be a complete dog below 5000 rpm with a huge kick with all the torque hitting at around 6000 rpm uptill the 9000 rpm.

Never mind. I dug up a dyno for you to look at the Ferrari F360 torque curve. With 78 ft-lbs/liter, all of the torque is concentrated at the top end. It makes a measly 164 ft-lbs of wheel torque at 3000 rpm. That is in an exotic car derived from Ferrari racing heritage that cost $200K back a few years ago. 164 ft-lbs@ 3000 rpm in a $200K car?? If you did not get what I meant by peaky, this is exactly the dictionary definition of a peaky engine. The powerband is all above 6000 rpm. Am I seeing "things" or according to you my "meds" are making me see a huge surge in torque curve above 5500 rpm??? Ofcourse, being a true race engine, the pure focus is high rpm torque and performance. The last thing Ferrari cares about is how a Ferrari should never need to be downshifted while lofting around 3000 rpm at 70 mph. If the new F458 is anything like this, all the torque will be concentrated at the top end, which it will be since Ferrari is all about pure high-rpm performance. The last thing it cares about is midrange and low end torque.

http://www.fabspeed.com/dyno27.html

What I get out of this is that, as per quoted specs, the E46 makes more torque per liter than the new one. Right? I don't give a damn where it peaks. I feel the current model has a more noticeable transition when the tach moves past high noon.

Pretty much every owner I've talked to or conversed with says that the M3 doesn't come alive until you get to the right-hand side of the tach, and of course that's also been my experience. Feel free to continue your disagreement.

Really??? Seems like you have a lot of faith in "butt dynos". Am I not correct to say that if there is a "dip" in torque curve or a "surge" anywhere like you said when the needle swings to the right side of the tachometer, it would clearly be seen on dynos???? No??? Is it not true that dynos never lie about the powerband and torque curve of a car???

If you believe that is true then please show me where exactly that "dip" or the "surge" is on this bone stock dyno since you claim there is a huge "surge". It should be on here somewhere so please point it out to me:

Here is a stock E46 dyno (notice it makes only around 205 - 210 ft-lbs of wheel torque uptil somewhere around 4500 rpm where it suddenly climbs upto 236 ft-lbs and then starts dropping as well).

By that account, using your 335 ft-lbs analogy on the basis of E46 ft-lbs/liter of 260 ft-lbs from a 3.2 liter, the E90/E92 M3 will be making only 228 ft-lbs at 3000 - 3900 rpm and NOT 260 ft-lbs of wheel torque :

Do you get my point?? You are harping about how E46 M3 produced more ft-lbs of torque/liter, but continute to demonstrate your ignorance by not even considering the fact that E46 M3 was far more peaky than E90/E92 M3 mostly because E90/E92 M3 was tuned by BMW with a far bigger priority for broad powerband while the E46 was not, which resulted in it becoming peaky and lacking midrange and low end. M5 V10 was similar to E46 M3 in the sense it had a surge at the top rpm for torque, but lacked torque down low. BMW learned their lesson during the development of E90/E92 M3 and decided to sacrifice some top end tuning to gain some midrange and low end torque.

http://www.dragtimes.com/2004-BMW-M3...phs-10186.html

E90/E92 dyno (staying at 251 - 260 ft-lbs of wheel torque all across the rev range until the last 200 - 300 rpm) so where is the "dip" you are talking about?

http://www.m5board.com/vbulletin/e90...st-result.html

And bashing? He said if I like low-end torque, get a turbo, etc., etc., and I said that's crap - because of course it is. The fact is that the only soft spot (other than abysmal fuel mileage) in an otherwise outstanding powerplant is that it's a little soft at low rpm, and a little shy on total torque. The other fact is that I have personally thrown more (and more eloquent) roses at this powerplant in this venue than you have.

Obviously, you never really understood the big picture of my post. My post was far bigger than the E90/E92 M3. You can call me M3 fanboi all you want, but go ready my post again, it was about high-revving engines in general and M3 was only one of the many examples I gave. Case in point, you must lose something to gain something. High-revving engines trade high-rpm performance while sacrificing low end torque. BMW targetted a flat torque curve and tuned it exactly that way to get the most broad torque curve they could possible attain so they actually "de-tuned" it to not produce the best top end torque it could possibly make, but ended up gaining a whole lot in the midrange and low end. If they had targetted tune for a higher peak such as, 310 - 315 ft-lbs of torque at a much higher 5500 - 6100 rpm, E90 M3 would be making 240 - 250 ft-lbs of torque@3000 - 3900 rpm and not 295 ft-lbs @3000 - 3900 rpm in the midrange since tuning for top end torque would have made it compromise the low end and midrange torque with a huge surge happening after 5500 rpm typical of most high-revving engines.

Have no idea what this means in relation to our discussion. We're talking about an engine that has a peak torque figure arriving at 3900 rpm and revs to 8400. What the hell is your point?

I tried my best before to explain it in simple words. If you cannot understand the concept of "area under the curve" in graph theory then you would never understand what my point is. Let me try again, Using peak torque arriving at 3900 rpm and having the powerband uptil 8400 rpm was just an example to prove how wide the powerband is contrary to what your "butt dyno" is telling you. There are no soft spots in there. It has a straight line going between 3900 rpm until 8300 rpm with very little variation.

So, if I get your drift right (you're a little tricky to understand when you're off your meds), if the M3 made its 295 pound feet at 3900, but peaked at 335 pound feet at 5200, wouldn't it be a better overall engine? Look, the fact is the new one feels a little lazy around town, partly because of its weight.

Obviously, you never considered the possibility that if M3 had been tuned for 335 ft-lbs @ 5200 rpm, most likely the tuning and part designed for more high-rpm torque and other things such as cams etc. would have caused it to lose torque down low. I used M5 engine as an example since this engine has been derived from it where there is a huge surge in torque above 5500 rpm. So instead of 295 -lbs@ 3900 rpm, it would have been making far less around 240 - 250 ft-lbs again because total tuning for high-rpm performance causes loss of low end and midrange. FACT!!!

Quite obviously, BMW managed to do it in the race version of the S65 4.0 Liter V8 in the ALMS M3 GT-R producing 500 HP@7800 rpm and 377 ft-lbs@6500 rpm yet decided to take a much different route in the road going production version for whatever reason.

The E90 is far ahead of the E46 in every performance measurement, so what's your point? It makes more torque and more power, and revs a little higher. As to your question: 268 pound feet out of 3.2 liters equals 335 pound feet out of four liters at the same torque per liter number.

See above for a direct dyno comparison. Look at their entire rev range.

Again, your comparison about peak torque is completely useless without considering the entire rev range. I am sure if it was possible to do in a dialy drivable car, it would have still be far more peaky than the E46 ever was. Simply put, there is NO mass produced 4.0 - 4.3 Liter high-revving production engine out there that makes a peak of 335 ft-lbs of torque. Period.

Our E46 didn't have that same sort of transitional softness that the new one has.

Really?? Look at the dyno above and show me where the soft spot, "surge" or "dip" in other words is.

If you were back on your meds, even you might agree - but of course as a fanboy you feel that any intimation the E90 has a bit of a soft spot around town must be crushed.

Meds??? Fanboi??? Insult me all you want. My point still stands that a high-revving engine give up low end torque and midrange torque to achieve high rpm performance and torque. Most daily driving oriented high-performance, high-revving engine end up getting de-tuned to sacrifice some top end power to get more midrange and low-end torque. That is the price you pay to get that unbeatable high-revving, high-strung melodic symphony and thrills of revving the heck out of the car uptil 8400 - 8500 rpm.

[M_Time]

I took delivery at the day of launch of a beautiful titanium silver / Black Manual Sport Package with allmost everything except Nav. What can I say, going from a 330i to the 135i was a big jump, the turbos spool very quick through the powerband at low RPM, loved it, small an nimble. The fun honeymoon lasted a short period of time, until was relocated to a sister branch at work and had to take lots of traffic on my daily comute, besides the car runs super hot 240 degrees was paranoid with the temp, specially here in Florida. Waited for the launch of the M3 allways dreamed of owning one, waited for the economy slide and traded in the 135i for an Alpine / Black with DCT payment went up slightly, but amazingly gas was not as bad as what I expected, the 135i was not doing better than 17MPG the M3 gives me about the same MPG. Couldn't be any happier !!!

[Zuzu]

Originally Posted by M_Time

I took delivery at the day of launch of a beautiful titanium silver / Black Manual Sport Package with allmost everything except Nav. What can I say, going from a 330i to the 135i was a big jump, the turbos spool very quick through the powerband at low RPM, loved it, small an nimble. The fun honeymoon lasted a short period of time, until was relocated to a sister branch at work and had to take lots of traffic on my daily comute, besides the car runs super hot 240 degrees was paranoid with the temp, specially here in Florida. Waited for the launch of the M3 allways dreamed of owning one, waited for the economy slide and traded in the 135i for an Alpine / Black with DCT payment went up slightly, but amazingly gas was not as bad as what I expected, the 135i was not doing better than 17MPG the M3 gives me about the same MPG. Couldn't be any happier !!!

Now that we are back on topic again, As I am considering the same trade up to a E92 M3..
You are happy with milage aswel as the DCT in city traffic?

[bruce.augenstein@comcast.]

Originally Posted by 330CIZHP

The new Ferrari 458 is almost a race car tuned for completely top end power. In terms of being high-strung, I would compare it to the F360 rather than much less high-strung F430 since F360 modena made more ft-lbs/liter than the F430 closer to the claimed F458. If you remember anything about the Ferrari F360 Modena (or know anyone who owns a Ferrari F360), go and ask him/her. Just do a search on the dynos of a stock F360. The car produced 280 ft-lbs of torque from only a 3.6 Liter V8. That is an impressive 78 ft-lbs/liter. Yet, ask any F360 owner and they would tell you the car was an absolute dog below 5000 rpm. All of the torque was concentrated above 6000 rpm uptill 8500 rpm thanks to a huge surge in torque. It was a top end monster, but a complete nightmare to drive in everyday life. Clutch modulation is extremely difficult due to a light flywheel, heavy clutch and lack of low-end torque. You have to slip the clutch like crazy to get it going. If the F458 engine is anything like the F360 where the engine was far more high strung than the Ferrari F430, it would be a complete dog below 5000 rpm with a huge kick with all the torque hitting at around 6000 rpm uptill the 9000 rpm...

So you say "Give me ONE example of a high-revving car that produces 84 ft-lbs/liter at ANY rpm, let alone at a low 2000 - 3000 rpm. ONE! and I will stand corrected."

...and I give you two examples, one of which you ignore (the E46), and you say the other doesn't count (before the jury is in) - rather than man up and say you stand corrected.

Hmm. I guess I can ignore any other challenges from you. Are you posting from a dorm room, by any chance?

OK, then you give me yet another sea of dyno runs, not knowing how meaningless they are, I guess.

Let's just cut to the chase here. What very large numbers of drivers report is that the current M3 is a little soft around town, and the car doesn't really seem to get happy until the tach needle is swinging past 4000 rpm.

Do you see how absolutely meaningless a dyno run is in this context?

At full throttle, nobody is bitching because you generally don't do that from 1000 or 1500 rpm, and the car is already starting to feel fairly lively before 3000 rpm, where you get to right quick because of the short gearing.

We're not talking full throttle, tough guy. We're just knocking around town.

I have no idea what BMW is doing with throttle plates and spark advance when you're just lazing around, but it's a fact that bunches of people, including me, think the car's a little soft down low. Doesn't make it a bad car, and some people just LOVE that it has that characteristic, but it's still a fact.

Do you think your dyno charts will show them they're wrong? Or will at least the knowledgeable ones think you have no clue when you quote dyno runs to "refute" a part-throttle situation.

Bruce

PS - Do NOT tell me a part throttle torque curve mirrors a full throttle torque curve, lest you reveal just how deep your ignorance is.

[MJC///M3]

Originally Posted by bruce.augenstein@comcast.

So you say "Give me ONE example of a high-revving car that produces 84 ft-lbs/liter at ANY rpm, let alone at a low 2000 - 3000 rpm. ONE! and I will stand corrected."

...and I give you two examples, one of which you ignore (the E46), and you say the other doesn't count (before the jury is in) - rather than man up and say you stand corrected.

Hmm. I guess I can ignore any other challenges from you. Are you posting from a dorm room, by any chance?

OK, then you give me yet another sea of dyno runs, not knowing how meaningless they are, I guess.

Let's just cut to the chase here. What very large numbers of drivers report is that the current M3 is a little soft around town, and the car doesn't really seem to get happy until the tach needle is swinging past 4000 rpm.

Do you see how absolutely meaningless a dyno run is in this context?

At full throttle, nobody is bitching because you generally don't do that from 1000 or 1500 rpm, and the car is already starting to feel fairly lively before 3000 rpm, where you get to right quick because of the short gearing.

We're not talking full throttle, tough guy. We're just knocking around town.

I have no idea what BMW is doing with throttle plates and spark advance when you're just lazing around, but it's a fact that bunches of people, including me, think the car's a little soft down low. Doesn't make it a bad car, and some people just LOVE that it has that characteristic, but it's still a fact.

Do you think your dyno charts will show them they're wrong? Or will at least the knowledgeable ones think you have no clue when you quote dyno runs to "refute" a part-throttle situation.

Bruce

PS - Do NOT tell me a part throttle torque curve mirrors a full throttle torque curve, lest you reveal just how deep your ignorance is.

Bruce,
I always enjoy reading your posts! I have learned an incredible amount of knowledge and thank you for the value you bring to the forum. My only question is how do you know so much about the inner-workings and engineering of these machines??...hahah...its very impressive!

As an owner of the M3, I def agree with you about the slight feeling of "softness" down low, most attributable IMO to the M3's weight. Not being picky, the car is a total gem but wouldn't mind to have a bit more down low ala the 335, 135; your aforementioned example of the E9X producing torque relative to what the E46 made would be extremely impressive.

[bruce.augenstein@comcast.]

Originally Posted by MJC///M3

Bruce,
I always enjoy reading your posts! I have learned an incredible amount of knowledge and thank you for the value you bring to the forum. My only question is how do you know so much about the inner-workings and engineering of these machines??...hahah...its very impressive!

As an owner of the M3, I def agree with you about the slight feeling of "softness" down low, most attributable IMO to the M3's weight. Not being picky, the car is a total gem but wouldn't mind to have a bit more down low ala the 335, 135; your aforementioned example of the E9X producing torque relative to what the E46 made would be extremely impressive.

Thank you for the plaudits, but some would call it an affliction.

Most of us retain information about things we're interested in, plus we tend to noodle about, ask "interesting" questions from people who actually know stuff, read everything we can, and make inferences to fill in the blanks. Those inferences can then be checked because we've accumulated enough knowledge to be able to correctly frame the correct questions.

One of my brothers in law was a plumber by trade. Made good money and retired at 55. Then he got interested in the stock market, and has played it like a Stradivarius ever since. By contrast, I advise people to listen to my opinions about finances and the stock market, and they'll get rich if they do the opposite.

We're all good at something.

Bruce