Press Release no 2: The new V10 engine in the BMW M5: A masterpiece in engine cons...

[beckhammania23]

for the Dutch people

www.automanias.nl and search to: Wereldpremière van de mechaniek voor de nieuwe BMW M5

[Apples]

Looking at the graph readout l'm not seeing near the normal usuable torque/ power curve like on the current M5.
It's well down on torque in everyday driving conditions of 2,000rpm - 4,000rpm
The V10 will only be stronger then the V8 past 6,000rpm.
My monies on the E39 being quicker at rpms below 6,000rpm...massive torque advantage over the V10.
As most of us know you spend very little time at RPM's past 7,000, so BMW is pushing peak power not what the E39 M5 was good at...torque down low.

Why a peak at 6,100rpm
The Gallardo has it's peak at 4,500rpm (510-520nm) it has a longer stroke then the bore diameter to help in touque production, and still manages to peak at around 7,600rpm.
The M5 has the shorter stroke this would help greatly in high end HP production.
Looking at the graph it seems the M5 motor would be better in the Gallardo and the Gallardo motor in the M5....

Another question is what do BMW do now that they've caught up to the 55 motors?
How do you find another 25+ hp from a 5 liter NA V10 thats at pretty hp limits as it is.

How can crappy CA 91 octane fuel (+ other states max octane rating) be getting anything near 500hp with a 12.0:1 compression ratio.
91 would crap it's pants at 12.0:1
A compression ratio like that is for 93-100+ octane...93 being the mimimum number here for strong power.
Sounds like a imprssive motor, but it's potental is very limited
What are your thoughts
APPLES

[Jessem]

Apples: some contrarian(and optimistic?) thoughts:

Octane: we have 94 here in PA, other than CA, where are you stuck with 91? Also, all engines suffer from poor octane. A forced induction engine cuts back on ignition/power when it preignites on crap gas just like the bmwV10 will.

I don't think that the E60 will have "caught up" to the e55 motors, I think they will have surpassed them. And the key from my perspective is the whole package, not just the engine. Such as lower weight, higher numeric ratio gearing, 7 speeds, etc. All of these will work to perform much better than the other sedans and even some of the supercars. What appears to be low torque numbers aren't going to translate to lower acceleration. I suspect it will drive like a cross between an M3 and an E39M5 until you reach 6500, when all hell will break loose! An remember, that 6500 will occur at lower road speeds than it does in the e39, so the effect will be to make the "apparent" or effective torque feel greater than it is.

Regarding the potential, as in, I assume, the potential to increase it's output, I'd agree it's limited. BMW took an approach that didn't leave much, if anything, on the table. Had they left much on the table, they couldn't charge what they will and also claim the laurels, which I'm sure they seek. Let's just hope I'm right and they have a real winner by a large margin. It'll be a requirement for many of us that don't yet lust after the exterior.

[Enigma]

Originally Posted by Apples

Looking at the graph readout l'm not seeing near the normal usuable torque/ power curve like on the current M5.

Just because the engine has a lot more power up top doesn't mean its much weaker lower in the RPM band. The engine has at least 80% of its peak torque available from 2750rpm to 8250rpm. Thats more than usable in my book. Even its its "weak" range its still making more than 75% of its peak.

Originally Posted by Apples

It's well down on torque in everyday driving conditions of 2,000rpm - 4,000rpm
The V10 will only be stronger then the V8 past 6,000rpm.
My monies on the E39 being quicker at rpms below 6,000rpm...massive torque advantage over the V10.
As most of us know you spend very little time at RPM's past 7,000, so BMW is pushing peak power not what the E39 M5 was good at...torque down low.

Wrong, see my first comment. The engine is within a few percent of the old engine in TQ pretty much from idle to the peak of the old block. Then it simply runs away and hides.

The old M5 was the exception rather than the rule among M cars in that it had a heavy and innefficient engine that made lots of TQ for its HP rating. The new block corrects that and returns to the M tradition not by making less TQ but by making more HP.

Originally Posted by Apples

Why a peak at 6,100rpm
The Gallardo has it's peak at 4,500rpm (510-520nm) it has a longer stroke then the bore diameter to help in touque production, and still manages to peak at around 7,600rpm.
The M5 has the shorter stroke this would help greatly in high end HP production.
Looking at the graph it seems the M5 motor would be better in the Gallardo and the Gallardo motor in the M5....

I suspect based on the graph and bore/stroke the engine is either underrated or detuned. BMW looks to have build a basic design that should be good to ~120bph/L. This will be one engine that will really respond well to a cam change.

Originally Posted by Apples

How can crappy CA 91 octane fuel (+ other states max octane rating) be getting anything near 500hp with a 12.0:1 compression ratio.
91 would crap it's pants at 12.0:1
A compression ratio like that is for 93-100+ octane...93 being the mimimum number here for strong power.
Sounds like a imprssive motor, but it's potental is very limited
What are your thoughts
APPLES

The limit on compression is based on detonation. With very smart engine controls you can run the engine conservativly under detonation risk condition such as low RPM and high load. Then when the RPMs rise and the intake starts to become a restriction the managment system can start to be much more agressive with its controls. This might explain the flat two step low RPM torque curve if BMW is running the engine conservativly until it can reach its ideal operating speed. With better fuel the system may be more agressive. Someone with a dyno will have to give it a try.

I know there are people on this forum that think they need enough torque to get in a tractor pull contest but it won't make the car any faster and will make it handle worse with the weight it adds.

If you are too lazy to shift the wonderfull new 7spd gearbox then perhaps an M car is not for you... Less wait for the rest of us that really understand what the cars are really about.

[MEnthusiast]

Apples,
I suspect the concern your comments point to are one of the reasons for that 7 speed gear box. Alter the gearing and the torque appears. I think the engine will be pleanty strong at any rev point.

[rvacha]

Originally Posted by Apples

How can crappy CA 91 octane fuel (+ other states max octane rating) be getting anything near 500hp with a 12.0:1 compression ratio. 91 would crap it's pants at 12.0:1 A compression ratio like that is for 93-100+ octane...93 being the mimimum number here for strong power. Sounds like a imprssive motor, but it's potental is very limited. What are your thoughts
APPLES

Apples-
I think the key here is that this engine has state-of-the-art pre-detonation sensors. Most engines use hall effect sensors that watch for small rotational perturbations in the rotational velocity of either the camshaft of crankshaft as an indication of pre-detonation. Its not a very exacting method, so some guardband has to be designed into the engine management. The M5's ionic pre-detonation sensors are placed in each cylinder. This coupled with individual butterflies and the ability to control injection and spark timing for each individual cylinder means the engine can literally "run on the edge" on every cylinder, every cycle. Certainly there is no escaping the fact that crappy gas will yield lower power, but the penalty will be much less severe in the M5 than in any other comparable engine.

Ray

[digger]

I think this question has been asked but does anyone have the torque curve (as published by BMW) of the e39 or know where it can be found. Do BMW have it shown in the owners manual like they did 20yrs ago.

cheers

[Apples]

I know the engine will adjust for the fuel, and thats my point, how much power do we loose with the cars we get from Europe.
I know there aren't too many 91 octane states out there, but l bet we could do a poll.

I agree, I do think the 7 speed will hide the lower RPM torque disadvantage.

The graph shows it's over 100nm 75lbft down on the V8 @ 2,000rpm and they never really meets till after 4,500rpm....again the 7 speed will help there.
The V8 made it's peak at around 2,000rpm and stayed flat till around 4,000rpm.

My guess is the top speed, unrestricted would be around 200mph, so shuffling through the gears will keep the E60 V10 on the boil and one very quick car.
I'm not sure the engine could have 120hp per liter in street trim from an engine that size...thats 500cc per cylinder, way above other cars that claim 115+ per liter now.
A short stroke is the only way to go if you want just big hp numbers.
S2000,360.
But saying that, it really depends on how much F1 has had imput into the engines life and potential HP figures in the future.
Maybe 550hp could be a chance, but my bet, is it wont be from this particular set up.
BMW is going to have to spend BIG $$$ if they want to get into a HP chase against Mercedes and that 55 motor...this isn't always a good thing.
BMW build complete well rounded cars that can have less HP then their competitors, and still be very competitive.
If the likes of Mercedes and Audi learn from what BMW do well, and take some of those qualities on then we could be in for some serious competition in the next 5 years.
BMW will have to focus on what they do the best, build awesome handling cars.
APPLES

[digger]

Heres a graphical comparison between e39 and e60 for torque.It is in the ***.doc attachment.

[Hollis]

I think one of the first things you could do for some added power would be to increase those valve-sizes; 35mm? That just seems a little small to me for a serious engine like this one. Then again, they may wind up doing something like this in a mid-production "spruce-up" ala E34 M5 and E30/36 M3's? I think if they did a bit more work on it, they could get five hundred fifty useable and street reliable horsepower out of this lump. Afterall, look at the S14. We can get 290+bhp (streetable, everday, power of course) out of a 2.5L engine that was pre-vanos and pre-motronic and pre-etc. So have a little faith!