Incidentally same reviewer also test drove the F-Sport versions of the IS300 and IS300h on the same track.

And it gives us a better look at the new Lexus test track built at Shimoyama.

 

Historically Lexus spent the time to develop products and capture all categories in the Lexus market both in products and sales position. However nowdays I do agree certain classes of vehicles have more attention then others. Having said that however, has the enthusiast crowd stepped up in meaningful volume when Lexus produces unique vehicles? The GS was the prime example; when it was launched and it out performed anything from Germany in its class, yet the core demographic Lexus owner didnt want it without massives amount of trunk money. Conquest buyers actually drove sales of the former, but now bloated 5 series (f10 model).

Same pattern with the F brand of models, same with the new LS. We dont know see many owners actively pursuing the LS500 as an upgrade path or buying the LC like its competitors in the price class.

While Lexus could outbuild the G20, the question would be, would the market care?
Cadiliac tried multiple times, infiniti hired exAudi and launched the redsport offshoot, Acura is trying with the TLX, volvo is trying with the SPA architures/polestar editions....the list goes on.

TLDR: Still think Lexus has lost its way, but I doubt the IS200/350/500 is going to move down from its current 4th best position.

 

Traditionally, the IS has outsold the butts off the A4, by about 20k/year peak; the IS only gives way to 3 Series and C Class.
However, you are right, unless the IS is fully replaced, it will continue to play 4th fiddle...

 

If you haven't test driven the M340, you really can't comment on the handling right. BMW also uses way more aluminum and the F30 was noticeably lighter than the IS350. The downfall of the F30 was the dead steering. The G20 mitigates much of that and now is near the top again. All of the cars in the class handle pretty well now but what distinguishes them is the powertrain and this is where the Lexus needs work to compete better. To the casual enthusiast, horsepower is more important than handling dynamics and its no wonder BMW still has a reputation for performance given the output of their powertrains.

 

Yes, I won't know how G20 really handles till I test drive it.
True, BMW's new OKL Oberklasse/Upper Class RWD-based platforms do have high aluminium content for significantly lower weight than the IS, in the realm of 400+ lbs.
However, do keep in mind that the IS has more compact dimensions, especially shorter wheelbase and narrower tracks [68 mm front & 64 mm rear] - for a lower Polar Moment of Inertia which increases agility.

Have you ever test driven IS and GS back to back?
Very little difference in weight and dimensions, yet my wife's 2&3.5IS will totally ambush my 3.5/4GS's.
My parents know little about cars, so they think all four cars handle essentially the same...

 

even with a lower Polar Moment of Inertia, there are many other factors than influence handling. The only reason the IS felt better than the GS was that it was both lighter and smaller and had the same powertrain and similar suspensions. But cars from other manufacturers have very different chassis and suspension components. Also, the IS350 was a good handler but it has its weakspots like terrible understeer near the limits. At this point, all the cars are competitive in the handling department. Its not the attribute thats going to influence the sales of the car.

 

Sure there are many factors affecting handling, but weight and Polar Moment of Inertia are some of the main factors.

German weights are tricky because it is the curb weight, plus the weight of options.
Whereas the IS's equipment is mostly standard.

IS and GS share the same New N Platform, they are similar in weight, and only a small difference in exterior size.
https://www.clublexus.com/forums/car...l#post10891135

However, there is a big difference in interior size.
Notice how IS has only 90 cu ft passenger compartment to GS's 99 cu ft?
Thus, the GS is a more "hollow" object with most of its mass concentrated at the ends; refer to the diagram of the Model 3 below.
The bigger the passenger compartment, the more the average mass is concentrated towards the ends of the car.
Hence a higher Polar Moment of Inertia.
Hence less agility.

Remember that the old 2012-19 F30 3 Series had a whopping 96 cu ft passenger compartment - almost the same interior size as the discontinued 4GS and the current 2017-24 G30 5 Series both @ 99 cu ft today!
That big hollow means that more of its average mass is concentrated on the ends of the car, for a higher Polar Moment of Inertia, hence less agility.

Now, the new 2019-26 G20 3 Series has contracted to just 94 cu ft; no doubt to improve handling?
Thus, the ageing IS with only 90 cu ft, has a smaller hollow, with more of its mass nearer the Center of Gravity, and this will benefit handling.

Engineering is often a compromize.
You want space?
You pay for it with handling!
It is very difficult to have both.

I will test drive G20 as soon as I get a chance...

The Model 3 does have a very low Center of Gravity, as well as a Low Polar Moment of Inertia - with the battery pack concentrating the mass towards the center.
However, the ageing lithium ion battery pack makes the Model 3 very very heavy; forthcoming solid state and graphene battery technology will address this, but this will take some time.

 

These designs fail to impress - good proportions but nothing particularly original here. I feel the same about Acura now.

 

Hi Ezz,

I finally test drove my friend's G20 330i with M Sport.

G20 is low, with low seats; nothing like the tall upright seats of the discontinued 2012-20 4GS.
However, 2019-26 G20 3 Series front doors are tremendously wide apart!
Remember how ageing IS and current 2014-21 C Class have 90 cu ft passenger compartments, but the old 2012-19 F30 was unusual in having a whopping 96 cu ft, which is only 3 cu ft short of discontinued 2012-20 4GS and current G21 5 Series - both with 99 cu ft?
The new 2019-26 G20 3 Series is now dropped down to 94 cu ft - which is still quite capacious, and only 5 cu ft short of 4GS and current 2017-24 G21 5 Series.
Thus, the G21 3 Series' very wide cabin may compromize the G20's Polar Moment of Inertia, leading to less agility.

I started the engine.
The 2.0 turbo is okay. Reasonably smooth and quiet, but never as smooth and quiet as a V6, which in turn is not as slick as a V8, which in turn is not as slick as a BEV.

I accelerated off.
On part throttle openings, I am personally very sensitive - I can feel the momentary turbo lag or flat spot as the turbine spools up to gather speed.
My bottom line is that all engines are compromizes; presently there simply is no perfect engine - just a set of pros and cons to each design.
At wide throttle openings, the torque and power is pretty good, but never exceptional.
Comfort and luxury-wise, my 4GS 3.5 V6 atmos purrs like a cat, while this 4 cylinder turbo is artificial and unrefined - horses for courses and each to their own.

As my friend switched between Comfort, Sports and Sports Plus mode, I notice the engine considerably louder.
Does this engine have artificial sound piped through the speakers?

Any how, the steering got heavier, and the damping much firmer.
Strangely, on the top Sports Plus Mode, I thought the damping might have been a tad softer, while steering heavier, and engine noise louder?

Dynamics:
Springing
Springing minimizes weight transfer to the outside wheels, to maximize grip on all four wheels, to provide more immediate and sharper turn-in [agility], as well as maximize the terminal grip on the skid pan.
However, the firmer the springing, the greater the ride deterioration, and the greater the car rides over the bump, rather than flattening the bump.

IMO, my friend's G20 coil springs are slightly firm, but slightly softer than my wife's IS200t.
When I dump the G20 into a sharp bend, the steering feels vague and imprecise; the turn-in does not feel as sharp as my missus' IS.

Unfortunately, I don't have a Correvit etc, so I cannot test speed through a slalom, nor terminal grip on a skidpan etc.

Damping
The damping is controlled by the hydraulic shock absorbers and their valving.
After the vehicle hits a bump and compresses the coil springs, the spring and hence the car will theoretically bob up and down forever.
Oil is forced through the shock absorber valving to convert the mechanical oscillatory motion into thermal heat, which is dissipated into the air.
A softly damped vehicle floats with a low frequency of oscillation, while a firmly damped vehicle has a high frequency of oscillation resulting in a tiring ride.
Damping provides the control, otherwise the vehicle "floats" all over the place.
However, excessively firm damping with high frequency oscillations is "tiring".

Missus IS200t does not have electronic variable shock absorbers which vary the size of the valve openings.
However, friend's 330i M Sport does have electronic automatically variable shock absorber valving.

IMO, both friend's G20 and missus IS200t are firmly damped.
I thought my missus IS200t was firmly damped, but on the softest Comfort Mode, my friend's 330i was even more firmly damped.
The G20 330i M Sport's Sports and Sports Plus mode makes the damping even firmer again.
Although less firmly damped than G20, my missus' IS200t never feels floaty; in fact, it is slightly too firmly damped [for me] in itself.

Missus old IS200t has 225/45R17 Bridgestone Turanzas.
Friend's G20 330i M Sport has 225R19 front and 255R19 asymetric Pirellis rear.

On civilian roads, I have not tested these cars at ten tenths.

Overall, missus' 3.5IS200t had the better ride.
Although the G20 has fractionally softer more compliant spring rates, the G20 M Sport's damping was way too firm, way too busy, even on the softest Comfort Mode - [for me anyway].

G20 has a very low profile ride comfort, and low profile noise levels.

The infotainment is tremendously more advanced than IS, and I will detail another time. G20 has a lot of electronic gadgets!
I have to wonder if all these electronic gadgets will breakdown and give the owner a headache over time?

I dump cars very hard into corners.
The average buyer will not toss cars around the limits like me.

Overall, I'd say the G20 handling is not as pin sharp as I would expect from its lighter weight on paper, but perhaps the G20 weighs far more when options are fitted.
Furthermore, there is always a compromize between interior space and chassis dynamics.
The bigger and hollower the cabin like G20's 94 cu ft, the more the weight is concentrated at the ends, to increase the Polar Moment of Inertia, thereby compromizing agility.

However, from a sales point of view, I can see the G20 Series peaking at 142,000 units/year USA just like its previous two generations in 2012-19 F30 and 2005-12 E90 3 Series.
The 3 Series styling, its interior space, its combination of engine, brakes, handling, comfort, equipment, heaps of electronic gadgets, with decent reliability will ensure tops sales in this segment for many years.

I would expect the ageing 3.5 major facelifted IS to continue on its 4th place ahead of Genesis G70 and Jaguar XE....

.

 

You should test the M340. The engine is entirely different. Much more powerful and the torque is fantastic. The inline 6 is easily as smooth as your V6. I had an is350 for 5 years so I know the V6 quite well. The V6 is nice and smooth but the lack of torque and pedestrian horsepower made me look elsewhere. You do realize the BMW is only 1.5 inches longer than the IS350 right. They are about the same weight. As I said again, they all handle well in this segment.

 

I have test driven 535i 3.0 TT many years ago, and the magnesium alloy in-line six together with the smaller 3.0 capacity both idles and revs much more smoothly than my Lexus's 3.5 V6 atmos; however just me, but I didn't like the typical turbo characteristics of the BMW, nor Benz's E400 3.0 V6 TT turbo characteristics either.
That said, the turbos do make much more power, while using less fuel, plus the smaller capacity has lower reciprocating mass to idle and rev much more smoothly, while the in-line sixes, thanks to straighter inlet ports, have superior breathing at low rpm relative to their V6 counterparts.

Yes, the G20 is only a smidgen longer and wider outside, but I guess the G20 is a good deal more hollow and capacious inside with 94 cu ft versus IS's diminutive 90 cu ft.
All of these cars handle superbly.
As a package, sure, the G20 will still be the class leader; IS needs 4IS, even if that is on e-TNGA platform.

 

You are referring to exterior design? Or something else? This refreshed IS is the best looking car in it's class while new TLX has killed it in midsize.

 

One factor you have not taken into account is strength/torsional rigidity of the chassis. There is always a trade off between lightness/agility vs rigidity/strength in chassis engineering.

A lighter chassis might not always translate to better driver feedback and responsiveness to driver inputs. Remember how the current generation 3IS spanked the F30 3 series in the slalom handling test despite being significantly heavier than F30?

It was because Lexus made the IS chassis stiffer and stronger than the F30. The result was that the IS was more responsive to driver inputs and felt more solid and assured performing high speed/high G maneuvers that would stress the car's chassis.

There were 2 main reasons why the 3IS was so heavy/rigid. Lexus took the already strong 4GS chassis and shrank it to make the 3IS chassis. On top of that, the 3IS chief engineer made further chassis reinforcements to the 3IS in order to make it a more driver-focused car compared to its bigger brother, further adding to the weight.

I am very interested to see how the 3.5IS chassis has been further improved after the Shimoyama track refinements.

 

True, torsional rigidity and bending stiffness is a possibility.
I did not test drive it long enough to ascertain the rigidity.
I will try to do another test drive.

 

The issue with the GS and as well as the IS is that there is no powertrain upgrade path. It begins and ends with the 3.5L V6, ok it starts with the mediocre 2.0L Turbo, but no one cares. If you are going to compete with someone, then compete with them at every level. Dont show up to a race bragging you have better shoes while you are overweight and havent trained for 10yrs. THey should have given the full fat 4.6L V8 as an engine upgrade instead of a 350hp detuned version for like a year. They could have given the LS a detuned, perhaps, 450hp 5L V8 to differentiate itself from the GS. But hey we got the spindle grill and that should add exactly 0hp so we should be good right?