The new QX50 engine techonolgy

Post by **oragex** » 19 Feb 2019, 07:19

The new QX50 Infinity has Nissan's Variable Compression Ratio Engine (a little bit long to write down). An interesting technology owned by Nissan

https://jalopnik.com/worlds-first-varia ... 1785295848

Post by **jimmy57** » 19 Feb 2019, 08:14

There seems to not be a payoff for all those extra pieces. The power output and MPG are meh.

Post by **June** » 19 Feb 2019, 10:08

Looks like a mechanical nightmare to me if it ever gave trouble! 1981 Cadillac 4,6,8 comes to mind... Ahead of it's time. Really only time will tell if this technology is sound. On paper it sounds good though. June

thebull · Post by **thebull** » 19 Feb 2019, 11:11

I`ve seen this perhaps more than 8 months ago. It is good to see these kind of engineering marvels once in a while. Practical - absolutely no. Will I buy car with this engine - NO. IMO internal combustion engine got the highest efficiency possible balancing reliability, performance, efficiency. There is no way to move 5000 - 6000lbs without burning that much fuel anymore. Solution - more high efficient drive trains aka electric, hybrid, turbine stop and go(complete BS). When I see those kind of innovations always thinking about the perfect machine and the perfect machine contains no moving parts. This - lots of moving parts - far from perfect.

Post by **oragex** » 19 Feb 2019, 11:15

Agree it's more exciting from an innovative point of view, than from a practical one. It's both a very possible extra headache and almost surely not something really needed. I wonder why Nissan simply didn't go the straight froward and very popular way of the turbo charged (or even supercharged like Volvo) 4 cylinder engines. Are they afraid of using a turbo ? They don't really have turbo engines in their line-up for some reason (at least I'm not aware). Nissan says this technology will save 30% in gas compared with their 3.5 V6 - only, basically anything compared with that thirsty V6 is going to be more economical.

I drove in the past the last Audi Q5 with that amazing 4 cyl 2.0T and not only that engine was so sweet at high regimes, but it was also pulling a lot and gave shocking mpg numbers even in city driving (also thanks to the 7 speeds transmission). So a 4cyl turbo is the way to go and it's simple to build, no reason to invest years and surely hefty amounts of money to develop some new tech. But, like said, it's not the practical side, rather the innovative side that's cool to see. Perhaps it will get forgotten in the history just like the Miller cycle did on the Mazda Millenia (another cool idea that didn't catch).