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Introducing The 2007 Lexus ES 350 The Car From The 'King of Kaizen'

When you’ve worked on a car in its variations over 19 years, you get a pretty good idea of what’s there—and what can be improved. And if you become the chief engineer, as Hiroyuki Hirata did for the fifth-generation Lexus ES, you’re bound to exceed all previous expectations.

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According to Bob Carter, the Lexus franchise is really built on three models: the flagship LS, the first luxury crossover RX, and the entry-lux ES sedan. The first will undergo a transformation later in ’06 that, in Carter’s estimation, is as thoroughgoing and as significant as the first LS 400 introduced in 1989, a car that quite literally rewrote the rules on what a Japanese high-end car could be. The LS 460 is said to be a car that will have the same sort of transformative potential (and it is one of the few cars that, when unveiled at the North American International Auto Show in Detroit, provoked an audible gasp from the crowd of otherwise indifferent journalists and hangers-on in attendance). The RX was not only the first luxury crossover (it went on sale in the U.S. in March 1998), but in the RX 400h configuration, it is the first luxury crossover hybrid. All of which is to say that when it came to the third of the franchise players, chief engineer Hiroyuki Hirata had a considerable cohort of vehicles into which he was to put a new product.

And the 2007 ES 350 is that product. The fifth generation of the car.

Yes, the platform of this mid-size sedan is used by the Camry, Hirata says. But he goes on to note that it is also used by several other Toyota and Lexus vehicles, including the Avalon and the RX. He explains that what they do is start with a building block that is then modified to suit the specific requirements of the vehicle. Consequently, engineering costs are amortized across a wider number of vehicles, which is beneficial to what the various chief engineers for these products can do.

 

REDUCE COST. INCREASE CONTENT.

Hirata says that one of the efforts that his team concentrated on during the development of the ES 350 was to reduce the costs of various components. But what’s interesting about this approach—and somewhat counter to what is sometimes performed by other vehicle manufacturers—is that the cost reductions aren’t being done so as to be able to increase the margins for the manufacturer. Rather, Hirata explains, the work was done so that there was the opportunity to put in additional technology. Simply: reduce costs on components wherever possible (i.e., they don’t have a negative effect on the product) and then put those savings right back into the product so that the net result is a better car.

(Masaki Sanayama, assistant chief engineer for both the Lexus RX 400h and the Toyota Highlander Hybrid, once explained that there is a different model followed by Toyota engineers when it comes to arriving at the price of a vehicle. While the typical approach is to have an equation that says “cost + profit = price,” what they do is to determine what the market will accept, then subtract the cost of production from that number. The remainder is then the profit. “Cost reduction is key to profit,” he said, and noted that it is up to the engineers to figure out how to reduce those costs. Evidently, this approach was used by Hirata and his colleagues.)

 

KAIZEN KING

Hirata has been working on the ES model for 19 years. This provides him with an up-close understanding of the vehicle and what can and should be done for the vehicle. Hirata says that for the four previous generations he was the assistant chief engineer. He describes his duties in that role: “to nit-pick, to find flaws, to second guess.” He admits that a consequence of that: “My colleagues gave me the sarcastic nickname “king of kaizen.” One can only imagine that someone who is given that moniker within Toyota certainly must be someone who is committed to improvement. As has been the case of late within the Toyota organization (e.g., the development of the new Camry), the chief engineers have been less methodical than one might expect: “Instead of beginning the project rationally, with a long list of engineering improvements, I focused on what the new ES should represent emotionally,” Hirata declares, adding, “Rather than improve the ES, our job would be to redefine it. My plan was to move the vehicle out of its entry-luxury ‘comfort zone’ and take it up class, to a new level of authentic luxury. And we would do this without significant cost-up and without sacrificing value.”

What’s important to consider here is the fact that whereas there has long been a criticism of products coming from companies like Toyota as being “emotionless appliances,” it is evident that while they’re giving nothing up vis-à-vis methodical improvement—after all, kaizen is far from being a random exercise—that they’re paying careful attention to the level of engagement that their vehicles can create with customers. They’re increasing their competitive capability 

 

THE LOOK OF LEXUS

The first thing one notices about the ES 350 is that it now has a familiar resemblance to the IS and GS models that have been introduced recently (see: Lexus GS: Talking Performance And Technology and Introducing The '06 IS); all of them share what is known in the Lexus design nomenclature as “L-finesse.” Which is to say that from the front of the vehicle, where the headlamps are pulled back and there are creases in the hood indicating that there is something of a serious nature back there, to an arc that projects back from the headlamps across the body of the vehicle to be resolved in the tail lamps and which forms a higher beltline than has been typical of the brand’s vehicles, to the back of the car, where there is a slight spoiler-like kick-up on the edge of the deck lid, there is a consistency in design that now indicates that the vehicle in question is a Lexus.

Dimensionally, the fifth-generation car has the same overall length of the fourth generation, 191.1 in. Inside, however, there is a feeling of greater spaciousness because the couple distance (measure of front to rear seating positions) is increased by 2.2 in. The wheels are literally pushed further to the ends of the car, as the front overhang is reduced by 1 in. and the rear is reduced by 1.2 in.

Under the hood there is a new V6, a 3.5-liter engine that provides 272 hp @ 6,200 rpm, which is 54 hp more than the previous engine, and 254 lb-ft of torque @ 4,700 rpm, which is an increase of 18 lb-ft. The engine features dual variable valve timing with intelligence (VVT-i), which controls both intake and exhaust cam timing, with the benefits being that there is better power, emissions, and fuel economy depending on adjustments to the valve timing (i.e., increasing or eliminating the valve overlap; advancing or retarding the closing of the intake valve). Although Toyotas have been long known for engines that run so smoothly that they’re almost imperceptible at idle, Lexus is further improving this characteristic by having a computer controlled engine mounting system. It features a fluid-filled chamber and high-power electric solenoid that imparts a direct force to counter primary engine vibration. There is also a new six-speed transmission for the ES, which replaces a five speed. This transmission is smaller than the five speed and has 20% fewer parts: another example of kaizen. Previously the transmission ECU was part of the engine control module; now the two are separate so that there can be more precise tuning of the processors. Communications between the two are via a Control Area Network (CAN) bus.

Hirata’s goals included having comfort and responsiveness, so the suspension was greatly modified. The subframe, for example, is made of high-strength sheet steel rather than the mild steel that is characteristic of the part. Although the base material is more expensive and the costs to stamp and weld it are higher, as well, it is said to provide improved strength and reduced vibrations. MacPherson struts are used in the front and there’s a multi-link setup in the rear. The anti-roll bar in the rear is interesting in that it is 5/8-in. diameter but instead of being a bar, it is actually a tube with a 0.11-in. wall thickness.

 

ELECTRONICS GALORE.

The ES 350 is in some ways an electronic array on wheels. There are over 100 sensors deployed on the vehicle to provide inputs on everything from the braking system (ABS, electronic brake force distribution, brake assist, vehicle stability control, traction control) to a “neural net”-based climate control system with automatic air recirculation control (e.g., the sensor can detect hydrocarbons and closes the recirculating door quicker than is likely to be done manually) to an optional dynamic radar cruise control system (that uses a milliwave radar phased antenna in the grille behind the Lexus logo).

Here’s an example of how nit-picking Hirata was for the vehicle. The wood trim for the ES, like all Lexus models, is prepared by Yamaha (think pianos, not motorcycles). Each piece is a matched set; because more than one supplier handles the trim before assembly, the pieces are digitally coded so that they’ll come together in a car. In the previous model, the wood was laminated to a fiber-reinforced plastic backing. For the new ES, there is an aluminum backing. Apparently, it helps improve the durability and appearance of the wood over the life of the vehicle.

This Could Be The Start Of Lexus’ Performance Division

One of the questions that gets posed to Lexus vp and general manager Bob Carter is “What about a performance division like Mercedes AMG or BMW M?” And the answer that he tends to respond with is along the lines of “We’re thinking about it.”

What Lexus ought to do, however, is to simply create the “h” high-performance marque, picking up on the unique nomenclature that they’re using for the Lexus hybrid vehicles. Case in point: the GS 450h. This is a 3.5-liter V6 hybrid that provides 0 to 60 mph in 5.2 seconds—besting the 4.5-liter V8 engine-powered GS 430. The GS 450, which was introduced in the fall of ’05 had been the fastest Lexus rolling. It didn’t take long for the Lexus engineers to supersede it. No other luxury manufacturer can offer hybrid technology in its ready-for-sale products, so creating the “h” marque would provide Lexus a distinct leg up on the competition. And let’s face it: the GS 450h is a niche vehicle, as Deborah Meyer, Lexus vp of marketing, says, “Our sales target for the GS hybrid will be limited to less than 2,000 per year.” They could probably sell that many in Hollywood alone. (“We expected nearly all of those sales to be incremental, attracting new buyers to the GS lineup, especially move-over buyers from BMW and Mercedes.”) Realize that there is also the RX 400h, the hybrid crossover that is positioned as a vehicle that provides the performance of a V8 and the fuel efficiency of something, well, smaller (the current EPA rating is 31/27 mpg for the all-wheel-drive version of the 400h; the RX 330, the non-hybrid version, is rated at 18/24 mpg).

The point of the 450h is power, not fuel economy. Now, there will be some commercial rhetoric about how “hybrid technology is good for the earth” and that, comparatively speaking, there are environmental efficiencies of the hybrid luxury performance sedan. But let’s face it: luxury and performance aren’t two words ordinarily associated with environmental issues. People who are interested in mashing that accelerator to the floor (the top speed for the U.S. version is 131 mph; the European model has a top of 149 mph) for a 0 to 60 shot in 5.2 seconds, or who are going 30 mph and want to get to 50 mph in a big hurry (2.7 seconds—that’s the advantage of electric torque) probably aren’t too concerned with the health of the planet: after all, the estimated rating for the 450h is 27/28 mpg and if they were really concerned, the Prius numbers are 60/51 mpg, and even if you knock a considerable percentage off of them, it’s still a whole lot better.

The GS 450h is the world’s first rear-wheel-drive hybrid vehicle. Like many performance rear-wheel-drive vehicles, when you mash the accelerator, the car takes off. But this one really throws you back in your seat because of the high-output, permanent electric motor that works along with the 3.5-liter V6 that has a dual-injection fuel system (port and direct injection) and provides 292 hp (or 218 kW) at 6,400 rpm. The two are combined with what is said to be the world’s first longitudinal hybrid transmission. The transmission packages both the 134 kW @ 13,000 rpm generator that’s used as the starter motor and the 147 kW @ 5,615-13,000 rpm drive motor that is used to drive the wheels in addition to the engine (although as a full hybrid system, the 450h can run on the electric motor only, although that is probably not too likely given its performance characteristics). It should be noted that because the design of this transmission, it wasn’t necessary for them to tear up the underbody for the existing GS platform in order to get it to fit (it is slightly longer than the 6-speed automatic transmission but heavier: 291 lb. vs. 187 lb.) The transmission has what’s called an “Electronic Continuously Variable Transmission” (ECVT) motor which has the effect of seamless acceleration. Which has an effect of making it seem as though there isn’t an available 339 hp when the accelerator is mashed: unlike conventional step-gear transmissions there isn’t that momentary pause that reduces inertial forces as the vehicle accelerates. Claims Shigetoshi Miyoshi, chief engineer for the GS, “It will accelerate from zero to 60 as quick as a 911 with Tiptronic. In fact, it is as fast or quicker than every V8-powered competitor in its class while delivering more than 30% better fuel efficiency.”

Yes, there is that fuel efficiency. But the GS 450h is PERFORMANCE writ large.

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