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Stumbled across this on a US site.

As everyone knows the Infiniti G series cars are the Nissan Skylines for the US Market.

The article says that as an entry level car, the next G series sedan will get a 2.5 turbo.

http://blogs.insideline.com/straightline/2...-auto-show.html

Could this be a comeback?

Whats interesting is that lately Nissan has been releasing cars in the US even before Japan so maybe its possible.

It'd make sense. A lot of companies, even those traditionally supportive of NA (Mercedes Benz, BMW, Ferrari) are considering going to a smaller displacement FI engine in the future.

With a VQ25DET already in production in the M35 Stagea (which shares the FM platform the V series uses), the R&D costs to get it to meet drivability/reliability/packaging/emissions requirements has already been paid for.

the VQ25det is an awesome engine, really it is only common sense that it.. or a larger :) displacement turbo find there way into the next generation skyline. It seems that Nissan likes to make 2-3 generations of boring skylines before each ripper one. Who knows.. maybe we're due in their eyes?

It'd make sense. A lot of companies, even those traditionally supportive of NA (Mercedes Benz, BMW, Ferrari) are considering going to a smaller displacement FI engine in the future.

With a VQ25DET already in production in the M35 Stagea (which shares the FM platform the V series uses), the R&D costs to get it to meet drivability/reliability/packaging/emissions requirements has already been paid for.

they stopped making the stagea 5 years ago......

they stopped making the stagea 5 years ago......

Damn.

Does anyone know if a turbo VQ25 is still being used by Nissan? Still, the VQ block itself is still meeting modern emissions requirements. I can't imagine it would be impossible to get a FI one to pass.

Damn.

Does anyone know if a turbo VQ25 is still being used by Nissan? Still, the VQ block itself is still meeting modern emissions requirements. I can't imagine it would be impossible to get a FI one to pass.

VQ25det was only used in the M35 Stagea.

Nowhere else.

It was discontinued at the end of 2004 due to not meeting the new emissions rules in Japan

Edited by iamhe77
*facepalm* reading american punters' comments makes my brain hurt.

bring on the VQ25HR Turbo!

Could not agree more. Amercans can't read and even when several people corrected their errors, others kept getting it wrong!!

Boy it's a real worry that they are considered the most powerful nation in the world.

More focus on Nissan VVEL technology, and less on idiotic Americans IMO!

stolen from thread stolen from my350z.com :D.

Nissan's new VVEL system is a completely different beast from their legacy VVL system. The two are not even in the same zipcode. BMW's Valvtronic is the only other system in the market that operates with the same concept in mind.

It's probably good I quickly summarize the different types of existing variable valve systems.

Type 1

- Nissan VTC/CVTC/EVTC

- BMW VANOS

- Toyota VVT-i

- Porsche Variocam

These systems work like adjustable cam sprockets, which allow advancement or retardation of camshaft timing/phasing and subsquently the valve timing/phasing. The re's the ability to alter settings in real-time and via infinite steps over a set range. Valve lift cannot be altered with these systems.

Type 2

- Honda VTEC

- Toyota VVTL-i

- Nissan VVL

- Mitsubishi MIVEC

These systems have the ability to switch between two (three in the case of MIVEC) cam profiles that are optimzed for different conditions. It is therefore possible to alter between discrete sets of valve lift and timing/phasing that are built into each of the available cams profiles. Discrete means the settings are not infinitely variable.

Type 3

- Honda i-VTEC

- Porsche Variocam Plus

This system is litterally the combination of Type 1 and Type 2 systems. Valve timing/phasing is infinitely variable, while valve lift remains one of the two fixed settings (a confine of Type 2 system).

Type 4

- Nissan VVEL

- BMW Valvetronic

These systems have continuous variable control over valve lift (from a mere crack to full stroke open), making standard butterfly throttlebody a virtual obsolescence. When coupled with their respective Type 1 systems they also gain continuous variable valve timing/phasing capability. These are the next generation control systems with FULL ABSOLUTE control over valve activities. Aftermarket camshafts will be all but unecessary because virtually any cam profile can be replicated via simple alteration of two ECU tables.

sounds like something else to stuff up and cost a buttload to fix. and i wonder how much lag they will have, since as it is the electronic throttles have some lag issues with lag, both when you put your foot down and when you lift off.

no i read it. ecu has full control over lift and duration of cams. and currently on some cars the ecu has control over the butterfly in the throttle body. and if you have ever driven a car with an electronic throttle you will know that sometimes you put your foot down and it takes half a second or a second before the car reacts to this, and sometimes you can lift off and it is half a second or a second before the engine reacts. yes i know that the new valve technology can do away with the throttle body, but my point remains the same. they currently can't make a simple electronic throttle assembly that works without lag, so what makes you think they can make a much more hi tech valve adjustment assembly that doesn't also have lag in the system?

and we all know that nothing electronic ever stuffs up.... i mean you never hear of problems with afm's causing a car to run like crap, or faulty o2 sensors causing poor fuel economy. or water temp sensors, or fuel gauge sensors or crank angle sensors. the list goes on of all the things that commonly start to play up on cars, however up until now they have only been controlling auxillaries which you can manage without (except the afm and CAS). if you happen to get a fault in an electronic cam system you may end up with it getting out of sync (maybe from a faulty CAS), and you could end up with the valves making friends with the pistons. sure that can already happen if the timing belt/chain breaks or jumps a tooth, but that happens much less than electrical problems.

and currently on some cars the ecu has control over the butterfly in the throttle body. and if you have ever driven a car with an electronic throttle you will know that sometimes you put your foot down and it takes half a second or a second before the car reacts to this, and sometimes you can lift off and it is half a second or a second before the engine reacts.

Those are primarily Version 1.0 problems with electronic butterflies.

I know a lot of people complain about drive-by-wire systems, but I've never had a problem with it on the VQ powering my Z33, nor with the MZR engine in the NC MX-5. I comfortably swap out of my cable operated Swift GTI into either car without feeling like its laggier.

I think, these days, pretty much all new cars are drive-by-wire since it somehow helps with emissions. I know the VQ's ECU likes to keep the throttle open for a split second after you lift for a gearchange, to keep the revs up, but from what I've read that's by design (it's some emissions thing) rather than a technical deficiency. Lightening my flywheel mitigated a lot of the effect.

What I don't like is the fact that the VQ's throttle butterfly starts closing itself at high RPM regardless of pedal position, to preserve the engine, but once again that's a design fault (that some ECU reflashes can remove) rather than an inherent shortcoming of the system.

Complaining that drive-by-wire is like complaining that turbocharged cars are really laggy. It might have been true when they were first productionised, but these days its pretty much been fixed and any current issues are a failure by the manufacturer, not the technology.

having full camshaft control opens countless doors for performance tuning, its a full f1 inspired step and very exciting, as for the fly by wire im not a big fan, but you can see why it is done in a production car.

i remember when i was an apprentice at Toyota, the first fly by wire cars were landcruisers. Toyota had one get away in a carpark, drove off a 12 foot ledge and squashed a couple of cars on landing. that was early days but still funny.

Also given the improvements in torque that direct valve control has could only be seen as an improvement in response.
It'd make sense. A lot of companies, even those traditionally supportive of NA (Mercedes Benz, BMW, Ferrari) are considering going to a smaller displacement FI engine in the future.

With a VQ25DET already in production in the M35 Stagea (which shares the FM platform the V series uses), the R&D costs to get it to meet drivability/reliability/packaging/emissions requirements has already been paid for.

Ferrari isn't going smaller displacement with a turbo, they are adding a turbo to their standard engines once they get rid of every single bit of turbo lag, It should be out in the "new Enzo" comming out in 2 years (i cant remember the name of the actual car that is being developed), they said something like electric motors may be used to keep the turbos spooled up at all times for instant acceleration that ferrari is known for

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