[richiemail]

I received my MY2013 520d couple of days ago, and (with the exception of not getting the old, not the all new Pro Nav system) I've been thrilled. So thrilled in fact that it's 2 days later before I opened on the bonnet to take a look at the engine bay. There I found something that puzzled me...

The Engine cover has "Twin Power Turbo" written across it. The 525d I know is now a 2L plant with twin turbos, and the 520d is 2L with single turbo. Is this just some marketing term for the single turbo or did the wrong engine cover (or god forbid wrong engine) get installed in the factory?

Can anyone else with a recent 520d tell me what's written on theirs?

Thanks.

[arnsbrae]

Interesting - I thought it said Twinscroll turbo on the F10 520d engine cover...

[Biogeny]

It's the new marketing name, it was one of the changes for the model year

[SomeRandomer123]

Neither the 20d or 25d is twin turbocharged. Both use a single TwinScroll turbocharger, acting as a twin turbo, hence twin turbo power. 16i/d to 35i/d - all single, TwinScroll turbocharged.

My 328i says the same on the engine cover

[HighlandPete]

Originally Posted by SomeRandomer123

Neither the 20d or 25d is twin turbocharged. Both use a single TwinScroll turbocharger, acting as a twin turbo, hence twin turbo power. 16i/d to 35i/d - all single, TwinScroll turbocharged.

My 328i says the same on the engine cover

F10 525d uses the N47S1 engine with sequential turbos. (Same as the F20 1-series 125d). The 520d uses the N47N engine with VGT single turbo.

Neither use a Twin Scroll turbo, that is primarily used in the petrol engine domain, like the N20 engine in the 328i.

HighlandPete

[Boss330]

Originally Posted by SomeRandomer123

Neither the 20d or 25d is twin turbocharged. Both use a single TwinScroll turbocharger, acting as a twin turbo, hence twin turbo power. 16i/d to 35i/d - all single, TwinScroll turbocharged.

My 328i says the same on the engine cover

Both the 525d and the 535d are in fact twin turbo'd. On the other, single turbo'd engines, the term TwinPower Turbo is a marketing term or relates to the twin scroll turbos on some engines.

Parts diagram for the 535d turbos:

http://www.realoem.com/bmw/showparts...88&hg=11&fg=50

and for the 525d:

http://www.realoem.com/bmw/showparts...78&hg=11&fg=50

And finally for the 520d:

http://www.realoem.com/bmw/showparts...91&hg=11&fg=50

As can be seen, the 25/35d have two turbos, the 20d only has one...

[richiemail]

Biogeny, I did go back and look at MPH's post on UK 2013 changes/additions this morning. And sure enough it states that 520d and 530d models now get "TwinPower Turbo" engine covers.

It says a lot that in a 520d, I even had a moments thought that it could be a larger engine. I came from a 2005 525d Auto (2.5L single turbo) which had been remapped to 211bhp (based on the mappers expectations, Simon from Emaps, who has a very good reputation). Once I get past the 1,200 mile run in period I can start giving it some beans. I suspect the old car will perform better in the higher rev range (>3,500rpm) that the owners manual tells me to stay out of for now. But in the low rev range, and combined with the 8 speed box that seems to use 5th gear for 30-40mph cruising it feels like a much more powerful car.

[arnsbrae]

Originally Posted by HighlandPete

F10 525d uses the N47S1 engine with sequential turbos. (Same as the F20 1-series 125d). The 520d uses the N47N engine with VGT single turbo.

Neither use a Twin Scroll turbo, that is primarily used in the petrol engine domain, like the N20 engine in the 328i.

HighlandPete

As Pete says, the term twin scroll only applies to petrol engines. Diesels get a variable twin turbo.

Per the Technology Guide...

Variable Twin Turbo Diesel.

Variable Twin Turbo technology takes the BMW four and straight six-cylinder diesel engines to unmatched levels of performance. It dual-stage design enables the engines to achieve performance figures that previously only larger eight-cylinder engines could reach. Emissions and fuel consumption, however, are impressively low.

Innovations such as common rail direct injection and exhaust gas turbo charging with variable turbine geometry have driven dramatic improvements in the performance of diesel engines.
The introduction of BMW's dual-stage turbocharging system, Variable Twin Turbo, represents another quantum leap in diesel engineering. This technology delivers a performance boost of 25 per cent, and enables instant responsiveness even at low engine speeds - as well as enormous reserves of power at higher revs.
The heart of the Variable Twin Turbo system comprises two turbochargers of different sizes. In contrast to the bi-turbo system, the two turbochargers do not operate parallel, but are activated at different points. Precisely coordinated, they run individually or together, increasing the pressure of the intake air to the optimum level. The greater pressure of the intake air enables a more effective combustion of the diesel fuel in the cylinder.
At lower engine speeds, the intake air passes through the inactive larger turbocharger into the active smaller turbocharger, which increases the air pressure. At medium engine speeds, the larger turbocharger becomes active, forcing air under pressure into the smaller unit, which increases the pressure still further. At higher engines speeds, the larger turbocharger alone forces air into the cylinders.
Despite these impressive dynamics, the fuel consumption of the Variable Twin Turbo diesel engine is exemplary low, according to EU standards. The standard diesel particle filter ensures that strict EU4 emissions standards are met.

[SomeRandomer123]

^^ Ahh, I can see where I've got lost with it all then!
Righty, so can we make a definite list? Amend if I get it wrong!

20d - Variable Turbo
25d - Variable Twin Turbo
30d - Variable Turbo
35d - Variable Twin Turbo

All petrol up to and including 35i, Single TwinScroll Turbo.

[arnsbrae]

Originally Posted by SomeRandomer123

^^ Ahh, I can see where I've got lost with it all then!
Righty, so can we make a definite list? Amend if I get it wrong!

20d - Variable Twin Power Turbo
25d - Variable Twin Turbo
30d - Variable Twin Power Turbo
35d - Variable Twin Turbo

All petrol up to and including 35i, Single TwinScroll Turbo.

See above, 520d is corrected! Dunno about the others...

Good idea to make a definitive list because on this one, Google is not your friend!

[SomeRandomer123]

Originally Posted by arnsbrae

See above, 520d is corrected! Dunno about the others...

Good idea to make a definitive list because on this one, Google is not your friend!

Ahh cheers!

Haha, no it certainly isn't!

[HighlandPete]

Originally Posted by arnsbrae

See above, 520d is corrected! Dunno about the others...

Good idea to make a definitive list because on this one, Google is not your friend!

20d - Variable Twin Power Turbo Now what is that???? Marketing speak????

2.0d has a single variable geometry turbo, known as a VGT or VNT turbo.

Hence with the BMW "Twin Power" nonsense, why everyone seems confused.

HighlandPete

[arnsbrae]

Originally Posted by HighlandPete

20d - Variable Twin Power Turbo Now what is that???? Marketing speak????

2.0d has a single variable geometry turbo, known as a VGT or VNT turbo.

Hence with the BMW "Twin Power" nonsense, why everyone seems confused.

HighlandPete

I think it's a wee bit more than marketing speak...

"The introduction of BMW's dual-stage turbocharging system, Variable Twin Turbo, represents another quantum leap in diesel engineering. This technology delivers a performance boost of 25 per cent, and enables instant responsiveness even at low engine speeds - as well as enormous reserves of power at higher revs.
The heart of the Variable Twin Turbo system comprises two turbochargers of different sizes. In contrast to the bi-turbo system, the two turbochargers do not operate parallel, but are activated at different points. Precisely coordinated, they run individually or together, increasing the pressure of the intake air to the optimum level. The greater pressure of the intake air enables a more effective combustion of the diesel fuel in the cylinder."

[HighlandPete]

Originally Posted by arnsbrae

I think it's a wee bit more than marketing speak...

"The introduction of BMW's dual-stage turbocharging system, Variable Twin Turbo, represents another quantum leap in diesel engineering. This technology delivers a performance boost of 25 per cent, and enables instant responsiveness even at low engine speeds - as well as enormous reserves of power at higher revs.
The heart of the Variable Twin Turbo system comprises two turbochargers of different sizes. In contrast to the bi-turbo system, the two turbochargers do not operate parallel, but are activated at different points. Precisely coordinated, they run individually or together, increasing the pressure of the intake air to the optimum level. The greater pressure of the intake air enables a more effective combustion of the diesel fuel in the cylinder."

520d doesn't have two turbos, just the same design of single turbo as they have had for years in the 520d. BMW are describing the 525d and 535d turbo set up.

Just look at the RealOEM details.

HighlandPete

[arnsbrae]

Originally Posted by HighlandPete

520d doesn't have two turbos, just the same design of single turbo as they have had for years in the 520d. BMW are describing the 525d and 535d turbo set up.

Just look at the RealOEM details.

HighlandPete

Check out the link below. First read what is written on the engine cover. Second read the description, which includes 4 cylinder engines...

http://www.bmw.com/com/en/insights/t...n_turbo_diesel

[HighlandPete]

Variable twin turbos don't come in the 520d, the engine pictured does not have the same turbo set up as the humble 520d. The description is not for the 520d engine.

Sure it includes 4-pot engines, but the higher output N47S1 engine, (525d) not the standard N47N as in the 520d.

The Twin Power thing is very misleading, IMO.

HighlandPete

[Dandle]

Twin power doesn't mean a twin turbo engine its a marketing phrase.

You can see clearly in this BMW video its a single turbo engine.

[HighlandPete]

Originally Posted by Dandle

Twin power doesn't mean a twin turbo engine its a marketing phrase.

This is a quote from Richard Aucock at Motoring Research.

Ignore confusing names for now: BMW muddles things with its TwinPower Turbo naming system. The assumption this means ‘twin turbos’ is incorrect, but it’s not entirely obvious what it does actually mean. Nor is the fact it means different things for different fuels.

I tend to agree, very muddled, as it appears BMW is applying the TwinPower label retro-actively to earlier turbocharged engines still in production.

HighlandPete

[arnsbrae]

Originally Posted by HighlandPete

Variable twin turbos don't come in the 520d, the engine pictured does not have the same turbo set up as the humble 520d. The description is not for the 520d engine.

Sure it includes 4-pot engines, but the higher output N47S1 engine, (525d) not the standard N47N as in the 520d.

The Twin Power thing is very misleading, IMO.

HighlandPete

I'm certainly confused...

Where does the twin come from in the engine cover wording. Is it a tribute to engines in other BMW cars!?

(That's a rhetorical question Pete...)

[HighlandPete]

^^^^

See my post above and the quote. Full post here.

http://www.richardaucock.com/bmw-tur...el-and-petrol/

HighlandPete

[SomeRandomer123]

I tell you what, it's a bugger when you don't know how many turbos your car has!

Confusing or what!

[arnsbrae]

Originally Posted by SomeRandomer123

I tell you what, it's a bugger when you don't know how many turbo's your car has!

Confusing or what!

Lol...

As long as we know how many cup holders we have we're sorted.