Rhambler

Well of course. If one can get to 60 faster than the other, I sure hope it would feel different. Power bands, gearing, the end results are the same on feel except one jumps to 60 faster.

Are you implying that two cars accelerating to 60 at the same times would feel drastically different if they had different power bands and gearing?

SW17LS

That's absolutely what I'm saying. You use the engines available torque at different points in the power band when you are driving normally. When you pull off from a light, when you pull out to pass a car. You're not always or even typically at WOT.

The LS460 has peak torque available at 4,000 RPM. This TTV6 will have it available at a much lower RPM and more of it. If you look at the TTV6 in the CT6 it's available about 2,400 RPM which is about what I would expect out of the 5LS, that makes the engine feel much more powerful in those lower RPM power bands where you typically drive the vehicle even if at a WOT 0-60 run there isn't much difference.

For instance I don't feel my LS460 is any more powerful feeling than my 430 or 400 even though the 0-60 time would indicate it is, and it has more power. But, it also has a lot more gears, its heavier, it's AWD. quite frankly, it doesn't feel a lot more powerful than even my NA V6 GS, although it's a lot smoother and more refined.

mmarshall

That, though, is where some people forget that when you are actually using that power while accelerating at lower RPMS, a TT V6 will probably use more gas than a N/A V8...the V6 fuel-savings don't really come into play until one is cruising on a level surface with a relatively light foot. But even that is sometimes questionable, since some modern V8s, such as the Chrysler 5.7L Hemi, shut off the fuel-injectors to one bank of cylinders at light-cruise and essentially run as an in-line four. Added to that is the need for turbo engines to use expensive, heat-resistant, full-synthetic oil and more frequent oil-changes (plus the possibility of turbo failure), and I'm just not sold on forced-induction.

SW17LS

Yeah fuel savings won't be huge. Look at the V6 G90 vs the V8, not much difference in FE.

The reviews I've read say that they don't see a reason to get the V8 G90...

TangoRed

Most engines nowadays are using synthetic and there is typically no difference in oil change intervals between forced induction and N/A vehicles.

SW17LS

Correct, the LS460 requires full synthetic oil already.

greg3852

But can you get the fully loaded Ultimate in V6 in the G90? I thought it was only on the V8 version.

peteharvey

I'm starting to get more experience driving my wife's new IS200t.
Engine mounts is very good, while sound insulation better again.
Pump the throttle & she goes.
The brand new early mileage drone is beginning to turn into a smoother four cylinder hum.

Driving gently around town at small throttle openings, there is that hum.
What I notice is at light throttle openings around town & 40 mph, the turbo is NOT on song, hence that hum.
If I then mildly accelerate while the turbo is NOT on song, then there is a four cylinder hum, and the vehicle feels like it's in naturally aspirated mode.

However if I use a much wider throttle opening (but not full throttle), then somehow the turbo kicks in, the car belts ahead, and the engine feel much smoother, with the four cylinder hum gone.

In other words, at very narrow throttle openings, gently driving around town, the engine is literally in atmospheric mode, with the turbo not on song, and the engine feeling lethargic with a four cylinder drone/hum.

It will be interesting to see how these new V6 TT's behave.

I don't think it's ideal, but I can now appreciate why Formula 1 racing cars & Benz' new in-line sixes said to be using "electric" turbos.
.

Rhambler

That's where most of the noticeable lag occurs in turbos: slow-speed rolling acceleration. I don't think anyone has been able to completely address it, although I remember reading about twin scrolls being slightly better in this department.

SW17LS

No, I believe you need the V8 to get the full package

coolsaber

As they say, if you need low end torque without much lag you go Supercharging, while on top end you need a turbo
Hence why twincharged Drive E engines are so good in terms of power (noise is another story).

I`m pretty sure the TT probs was designed to achieve the needs of the many focus groups Lexus employs during development. Plus with smart adaptive transmission programming they can also reduce the lag that might be experienced with typical handover between turbos

Bogglo

"Within the five years to the end of 2021, Toyota plans to introduce 17 versions of nine engines, including the 2.5-liter engine announced today, 10 versions of four transmissions, including multi-geared automatic transmissions and a new kind of continuously variable transmission, and 10 versions of six hybrid systems. In this way, through TNGA-based modular development, Toyota will roll out numerous types of new powertrain units within a short timeframe, successively introducing them in various vehicle models, starting with the launch of a new-model vehicle in 2017"

Just maybe a V8 is in there somewhere. We still in Jan with 11 months to go.
https://lexusenthusiast.com/2016/12/06/toyota-announces-new-engines-new-transmissions-new-hybrid-system/

Toys4RJill

Gonna be pretty cool that this new LS is going to have rear wheel steering. Car & Driver is also pretty sure a new V8 is en route.

mmarshall

Twin scrolls are superior because one of them can be kept spinning at low RPM to provide at least an limited amount of boost available almost instantaneously, without lag, while the other one is spooling up. Then, of course, when both of them are spooled up, you get your max torque. That's an old trick going back to the 1990s......but it still works.

LOWFAST

FYI.

http://www.superstreetonline.com/how-to/engine/modp-0906-twin-scroll-turbo-system-design/

You are a bit off in your understanding. You can have compounding dual turbos aka Supra and rx7, one smaller and one larger. Twin scroll refers to the design of a single turbo and the internal routing to give quick spool and good top end. Another type is variable vane turbos.

Today's BB turbos spoil so fast, and in this case will be so small that lag is really a non issue, at worst it is more of a slight hesitation at throttle tip in. Nothing like the old 930 turbos of the 70's and 80's of all or nothing.