A shameless image thread for the enginephiles

[roon]

VC-Turbo - the world's first production-ready variable compression ratio engine

The VC-Turbo engine is the world's first production-ready variable compression ratio engine, transforming on demand. A breakthrough in combustion engine design, the 2.0-liter VC-Turbo engine adjusts its compression ratio to optimize power and efficiency. It combines the power of a 2.0-liter turbocharged gasoline engine with the torque and efficiency of a four-cylinder diesel engine. A compelling alternative to diesel, it challenges the notion that only hybrid and diesel powertrains can deliver high torque and efficiency.

The VC-Turbo offers any compression ratio between 8:1 (for performance) and 14:1 (for efficiency). The engine delivers 268 hp (200 kW) and 280 lb ft (380 Nm), an expected best-in-class combination of four-cylinder power and torque. Front-wheel-drive models offer a 35% improvement in fuel efficiency over the previous V6 gasoline QX50; all-wheel-drive models offer a 30% improvement.

Cool to see this going into production. They say they've been working on it since '96. The mechanism was invented in '98.



















*Note oil jet in image above.

[e36jon]

I seem to remember Saab also having had a variable compression ratio engine. A quick Google verified my memory for once. Looks like Saab moved the head / combustion chamber:





Apparently it never went to production (Circa ~2000) due to costs. Images are from Saab.

[roon]

I remember it as well. Someone or some legal entity might be sitting on the patent for it, or it truly wasn't a cost effective approach, as you say. The advantage of the Infiniti design is that it keeps the block and head as a rigid unit, unchanged from a traditional engine assembly. The key developments were to the crankshaft assembly. The SAAB passes compression and combustion loads through the mechanism, and requires a big rubber gasket to seal the crankcase.

[Manoah2u]

performance figures are imho worthless if not also shown with real-life efficiency applications (and then performance, too).

Let's say a current SUV does on 1 litres of gasoline about 15 kilometers. 30% more efficiency then ups it to about 1:20.
offcourse that's a lot better, BUT is that the actual daily use figure? and what's the cost for having this engine in your desired infinity car?

don't get me wrong, i like these technological 'advances' - even if i wonder whether you can call a 20 year old design anything like technological advancement.

wouldn't a hybrid be far more efficient anyway?

[J.A.W.]

Yeah, I note that mention of RPM is absent..

With all that extra mass to whirl about, its not gonna be a sporty unit..
So, maybe as analog/replacement for diesel, facing a pending ban for particulate emissions?

[Tommy Cookers]

can't find a picture of the 1980 Yamaha 001A 500cc GP V4

28 valves 70 bore x 32.4 stroke and 123 bhp at 18000 rpm

[roon]

can't find a picture of the 1980 Yamaha 001A 500cc GP V4

28 valves 70 bore x 32.4 stroke and 123 bhp at 18000 rpm

[roon]

[roon]

[roon]

Yeah, I note that mention of RPM is absent..

With all that extra mass to whirl about, its not gonna be a sporty unit..
So, maybe as analog/replacement for diesel, facing a pending ban for particulate emissions?

Yeah, they themselves compare it to a diesel engine. Interestingly, it's being paired to a CVT exclusively for this its first MY. So the CVT has no prob with the extra low RPM torque apparently. Diesel torque + CVT seems to be a rare combination in the auto world. I don't know of any other examples.

Maybe the CVT is gentler on the engine, and they'll pair it with autos or manuals in time, as the technology is validated in the real world.

[rkn]

It just won't ever be the same.

[roon]

Mecachrome LMP1 hot-vee-6 turbo in development.

[bill shoe]

can't find a picture of the 1980 Yamaha 001A 500cc GP V4

28 valves 70 bore x 32.4 stroke and 123 bhp at 18000 rpm

Since we're pondering engines with more than 4 valves/cyl, here's the 8 valve/cyl Honda oval-piston engine. Yes, it's kind of a cheater for purposes of this discussion because each combustion chamber is a pair of 4 valve/cyl combustion chambers siamesed together. But these devious methods are precisely why this engine is so epic.

[r101]

Since we're pondering engines with more than 4 valves/cyl, here's the 8 valve/cyl Honda oval-piston engine. Yes, it's kind of a cheater for purposes of this discussion because each combustion chamber is a pair of 4 valve/cyl combustion chambers siamesed together. But these devious methods are precisely why this engine is so epic.

I remember this! It was on NR750 and 125 HP from that displacement was kinda big deal in 1992.

[roon]

can't find a picture of the 1980 Yamaha 001A 500cc GP V4

28 valves 70 bore x 32.4 stroke and 123 bhp at 18000 rpm

Since we're pondering engines with more than 4 valves/cyl, here's the 8 valve/cyl Honda oval-piston engine. Yes, it's kind of a cheater for purposes of this discussion because each combustion chamber is a pair of 4 valve/cyl combustion chambers siamesed together. But these devious methods are precisely why this engine is so epic.

https://motovue.files.wordpress.com/201 ... 21zyo1.jpg

Why stop at two? Get a straight six, do this... world's longest twenty-four valve single cylinder.