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Petrol/Gas BMW B58TU2 petrol engine revision for 2022 will we get this version?

bemax

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My intention was not to compare diesel and petrol, but rather torque v power. Engine torque is great for a manual, but makes no difference in an auto. An auto trans produces your wheel torque from power alone. That power is produced by a proportional combination of torque and rpm. Power is what accelerates your vehicle, whether it be towing, hill climbing or even towing. A more powerful engine will do it quicker.
Sorry, but I do not get your point. Power is always the product of speed (rpm) and torque. Why should there be a difference between a manual and a automatic transmission?

I found some good explanations here but it is unfortunately available only in German

(https://www.bmw.com/de/performance/drehmoment-bei-autos-erklaert.html)
 
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TD5-90

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I have the same setup in my Mercedes.
Goes like stink with hardly any turbo lag.
It is only a 2.1 L 4 cylinder with 204 HP and 500NM
Offer 2.0l 4 cyl 240HP 500Nm. Same setup also.
Passat Alltrack BiTDI.
Time behind the wheel on an Autobahn part with not too much traffic is one of the few situations to enjoy Deutschland nowadays....
 

Eric

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TD5-90

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G-Man

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Most modern autobox torque converters incorporate a lockup clutch which makes a solid connection between the two halves of the torque converter once they match speeds (which is why modern autos are far more fuel efficient than their predecessors). Before the lock-up clutch is engaged, the amount of torque produced by the torque converter varies and it can actually be designed to magnify torque from the engine, but once the lockup clutch is engaged and you're cruising in the same gear then engine torque in = torque out of the converter.

For engines with older auto boxes, the maximum engine torque produced did not directly relate to the amount of torque coming out of the converter, so engine power was more important as it was able to produce a certain amount of torque quicker, if that makes sense. For modern auto boxes where the transmission spends a lot of the time with the torque converter locked directly to the engine output, the torque characteristics of the engine become much more relevant to how the vehicle drives.
 

bemax

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so the torque multiplication only is from interest when starting to drive. Afterwards the lockup clutch is engaged and everything is as I wrote.
I stay with my diesel :cool:
 

TD5-90

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so the torque multiplication only is from interest when starting to drive. Afterwards the lockup clutch is engaged and everything is as I wrote.
Not quite.
The clutch opens e.g. if you're cruising and then are accelerating quickly or using kickdown: Engine rpm "jumps" to the max POWER(!) rpm, with the respective torque. Obviously, gearbox IN rpm/torque now doesn't match OUT rpm/torque, and the torque converter matches this mismatch by making the product
rpm_IN x torque_IN = rpm_OUT x torque_OUT (neglecting losses). Since rpm_OUT (equivalent to vehicle, or more precisely, tire speed ;-) ) cannot "jump", torque_OUT will jump and give you a kick in the back.

So, IMHO, @Disco_Dave is 100% right.

That's more or less the (only/main) reason why my colleagues Audi A4 with 270hp and ZF HP8 has _so_much_ better overtaking performance than my 240hp Passat with DSG: He's overtaking always with full 270hp, whilst I am stuck with the current rpm x torque my engine is willing to put out....

I stay with my diesel :cool:

Staying with diesel is always right, independend of the gearbox type ;-)
 
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Disco Dave

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Sorry, but I do not get your point. Power is always the product of speed (rpm) and torque. Why should there be a difference between a manual and a automatic transmission?

I found some good explanations here but it is unfortunately available only in German

(https://www.bmw.com/de/performance/drehmoment-bei-autos-erklaert.html)
In a manual you select your gear, if are in too high a gear, a high enough torque will still accelerate you. Too low a torque and you won’t. Having higher torque at low engine rpm, means you have higher power at low rpm.
This makes high torque very advantageous in manuals.
However, an auto will shift down until the engine has enough rpm to provide enough power.

In a manual, it is not always convenient or possible to change down. An auto trans will ensure you have enough engine rpm to get you out of the low power zone.
 
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A high torque engine just produces its power at a lower rpm. It is all about power in the end. The IG petrol engine requires about 20% more rpm than the diesel, to produce the same power. Behind an auto transmission (this is important), the torque to the wheels becomes the same. So the argument of power and torque become mute. The amount of torque you can provide to your wheels is directly proportional to the engine power, not the engine torque.

Now the rpm of the B58 in the IG, has had the max rpm reduced. We are told this is in the interest of longevity. Also, generally a Diesel engine of the same capacity as a petrol needs more turbo boost to gain the same power. So probably the diesel will have more turbo lag than the petrol. Turbo lag can be a real pain on rough tracks.
Well said Disco Dave, it is all about power at the end of the day, if you can keep it on song you will always win, but I am getting the B57 for economy, and the ZF HP76.
Old petrol motors "carbureted usually had a narrow torque band, modern common rail fuel injected petrol motors have a much wider torque band, and combined with a high stall torque converter, and 8 gears the B58 will always be on song.
 
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Norb-TX

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Hopefully Ineos gets the new engine soon. Carbon buildup on direct inject BMW's was/is a big problem. The dual injected solution is best. In fact, Toyota didn't start using direct inject until it came up with the dual inject system.
 

emax

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Upon my last visit at my agent (some weeks ago) I was told that the "demonstator" car already had the latest version of the Diesel engine.
 
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