Variable Compression Engine

Not the power output I was quoting, no. A variant of, yes.

spaz said:
I "hope" you're (best engined) car doesn't. Blow up. Again as I can't afford to give you another 'tenner' for it
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Useful (illegible?) addition to the thread. Do you want it back with interest and inflation?

My days of running my only road car on a track are over.
 
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paradigm said:
What? How is it "huge"? If it was a 27% improvement over a comparable "traditional" 2.0 4-pot, then yes, I'd agree. Comparing it to a different layout, with a different cylinder count, a different breathing method, and a massively different displacement is hardly ground-breaking.

Simply by buying in a Gen 3 EA888 VAG 2.0 petrol TFSI engine they could have had 48% fuel efficiency over the same 3.5l V6.
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Maybe they were talking real world? No turbo is quite an improvement and means it drives like an NA aswell as the improvements for emissions, this engine may well get away with EU6c without GPF, unlike maybe that EA888 unit.

Nice to see port and direct injection to avoid carbon build up aswell.

27% is huge.
 
paradigm said:
Wow, a whole 27% more efficient than a large displacement N/A V6. That's well worth the investment, production and maintenance costs.

Now compare it to a cylinder on demand turbo 4-pot.
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Cast iron manifold to deal with the exhuast heat? Loads of hoses, and intercooler, high specification turbo charger and shorter oil changes.

Yes you make a good point, oh wait you were talking about this new engine. :o
 
[TW]Fox;29906010 said:
27% is incredibly good in terms of efficiency gains surely?
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Again, if you were talking apples with apples, yes.

How much of the efficiency gains above the old N/A 3.5l V6 come from the smaller displacement and use of forced induction? How much of it actually comes from the variable displacement/compression ratio?

I'd wager most of the "efficiency" gains over the far larger (75% more displacement) N/A V6 don't come from the complex new tech.
 
Nissan/ Renault dont really need to go down this complicated route as Ghosn has committed to EVs, will be interesting if it sees light of day although i suspect its height will limit applications.
 
paradigm said:
Again, if you were talking apples with apples, yes.

How much of the efficiency gains above the old N/A 3.5l V6 come from the smaller displacement and use of forced induction? How much of it actually comes from the variable displacement/compression ratio?

I'd wager most of the "efficiency" gains over the far larger (75% more displacement) N/A V6 don't come from the complex new tech.
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They quote that is new VCT engine has similar HP/torque to the 3.5L V6, but is 27% more efficient. What sort of efficiency do current 4 cyl turbo engines with similar power get compared with the V6? That's the real test of how much of an improvement it is.
 
I quite agree, however back to the (yes I know, I sound like a fanboy, but in reality it's just because I've done reading up on this particular engine so know it's comparable) Gen3 EA888.

The Gen 3 EA888 with 300PS has book figures of 295BHP, 380NM Torque, 160G/KM emissions, and a quoted economy figure of 40MPG.

The 3.5L V6 in a similar state of tune (in the 350z) has book figures of 295BHP, 353NM Torque, 280G/KM emissions, and a quoted economy figure of 24MPG.

As you can see, the VAG unit smashes the 27% increase in economy.
 
paradigm said:
The Gen 3 EA888 with 300PS has book figures of 295BHP, 380NM Torque, 160G/KM emissions, and a quoted economy figure of 40MPG.
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Wow, that seems poor. The 340i has lower CO2, similar economy, more power and torque and the correct cylinder configuration.

Is the VAG engine really old now or something?
 
In which case the engine in the 340i sounds incredible :cool:

And certainly makes a mockery of the new Nissan VC-T.

And yes, the EA888 is getting quite old now, sure Gen 3's aren't particularly old, but the engine as a whole has been around since 2008.
 
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Actually the EPA tests are excellent and represent real world figures. But they are also US figures, do you mean the NEDC figures?

Either way I'm not sure what your point is as both numbers are from the same testing source. I don't dispute the accuracy issues but it will apply to both.
 
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