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Thermostat, Thy Days are Numbered

We tend to get the impression that the tectonic plates of automotive technical advance are undergoing a virtual stutter-step when, in the space of a month, we're chatted up by no fewer than three big-name suppliers and one highly experienced independent engineer all on the matter of the same subject: electronic control of engine cooling. Before long, you likely will know this technology by many names.

We tend to get the impression that the tectonic plates of automotive technical advance are undergoing a virtual stutter-step when, in the space of a month, we're chatted up by no fewer than three big-name suppliers and one highly experienced independent engineer — all on the matter of the same subject: electronic control of engine cooling.

Before long, you likely will know this technology by many names. And the fact is, rather than mention who's got electronic engine cooling systems in the works, it might be easier to list who isn't working on this concept.

Visteon Corp. is far enough along to already have a handy tradename: PrecisionCooling. Engineer, entrepreneur and President of EETC, Thomas J. Hollis, favors a more straightforward approach, dubbing his proposed system Electronic Engine Temperature Control (hence the “EETC” in his company name). Robert Bosch GmbH for now appears to also prefer a no-nonsense description, referring to its system as “electronic engine thermal management.”

The names don't really matter — for all of these competing systems, the target is the same: precise, electronic control of engine cooling (and heating) via a closed-loop system that drastically improves on the rather crude little device that governs the operating temperature of virtually all contemporary internal-combustion engines: the thermostat.

Watch that kind of slander, you might say. Gross its ministrations may be, but the simple and inexpensive thermostat's served the industry well for nigh on a century.

Yes, but stand back, ye of the Thermostat Admiration Society, and face facts. Almost every other mechanical “system” related to engine management has succumbed to the ever-watchful electronic eye — except in the critical matter of temperature regulation.

Fuel delivery? Electronically controlled and metered, either indirectly via the intake manifold or directly in the individual cylinders.

Spark? Come on, mechanical points and condensers are buggy whips. Spark has been electronically controlled for decades.

Even valving, the intake and ejection of gases, in many cases is under some form of electronic management. Although mechanical camshafts still actuate the valves, variable valve timing, usually through electronically regulated camshaft phasing, now is common. And we're but a few years away from genuine electromechanical or electromagnetic valve actuation, sending the camshaft to the museum to join the carburetor.

The only engine system still resisting the electronic schoolmarms is temperature control. According to Visteon and Bosch, the beginning of the end for “analog” engine thermal management will come around 2004, the model year both suppliers claim will be Job One for the new era of electronic temperature control.

Mr. Hollis intrigues as the wild card, though. His claims for his EETC system are backed by years of research and personal endeavor.

A graduate of General Motors Institute and the self-proclaimed “father” of the backpressure exhaust gas recirculation (EGR) valve, he also was involved in a star-crossed “vapor phase cooling” program at a New Jersey company called Vacor after he left GM in 1982. That's where some of his early EETC data was acquired. Eleven years later, in the offices of one of the world's largest thermostat makers, he had the epiphany: “analog” control of engine temperatures — regulated only by a dumb thermostat — was a thing of the past.

Today, Mr. Hollis engages in an overwhelming presentation of charts and graphs — data gathered from years of EETC research and more than $1 million invested by his original backer, Windfall Products Inc. (later purchased by MascoTech, which itself now has evolved into Metaldyne).

Despite years of tireless development work and the bigfoot suppliers lurking with their own production plans — he claims at least ten suppliers are developing similar systems — Mr. Hollis humbly admits that despite holding more than two-dozen related patents, he's still “looking for a partner” to bring his EETC system to production.

“I'm interested in having someone take 100% control and I might get some royalties,” he says of his work. “The thing is, it was fun to do — and it (EETC) really works.”

Really works at what, exactly? On these points, all the entities engaged in development of electronic engine thermal management agree. The systems will:

  • Improve fuel economy by as much as 5%, depending on a variety of operating conditions.

    Visteon's David Piccirilli, PrecisionCool system engineer, says fuel consumption is reduced because the system allows the engine to operate at consistently higher temperatures — thus reducing friction. Also, the power draw from engine ancillaries is reduced; with electronic engine thermal management, the water pump — by necessity, now also an electronically controlled, “clutched” component — often does not operate, meaning considerable reduction of engine parasitic losses.

    In a discussion of its electronic engine thermal management system, Bosch reminds that higher engine temperatures translate to lower oil viscosity and thus less friction.

    Interestingly, Ford Motor Co. says one of its “tricks” to slightly enhance fuel economy is its recent decision to begin specifying low-viscosity oil for a number of its engines. With the proposed electronic engine temperature control systems, “You don't have to do that because you run at the highest optimum temperature all the time,” says EETC's Mr. Hollis.

  • Reduce emissions by more quickly bringing engines up to optimum temperature, then precisely stabilizing engine temperature irrespective of engine speed or load.

    “Everybody will infringe on my patents.”
    — Thomas J. Hollis
    President, EETC

    Cold-start emissions — primarily hydrocarbons (HC) — thus are minimized, and the elimination of temperature “spikes” typical of a conventional thermostat-controlled cooling system helps to reduce overall emissions output.

  • Enhance passenger comfort by delivering hotter air — more quickly — in cold ambient conditions and improving air-conditioning “pull down.”

    Visteon's Mr. Piccirilli says that with PrecisionCool, his company has recorded a 5.5½ F (3½ C) reduction in air conditioning temperatures at the outlet. Similarly, delivered heat is 18½ F (10½ C) toastier — and nobody in Minnesota's gonna argue about that on a mid-February morning.

  • Mr. Hollis claims there are potentially huge savings by extending oil-change intervals. He says that if every car running in the U.S. today had an EETC-type system, the oil-change interval could be tripled and 80 million fewer oil filters would be interred in landfills over a ten-year vehicle lifespan.

As can be seen from the accompanying graphics, the move to electronically controlled cooling is going to require a few items that aren't currently considered “off the shelf.”

First, there's some sort of “smart” multi-port valve or valves that replace the thermostat to more precisely regulate and route coolant flow. Also non-negotiable is an electronically controlled water pump — either fully electronically driven (read: 42-volt vehicle electricals) or at the very least, mechanically driven but electronically controlled and clutched to run independent of the engine.

Finally, some sort of control module. At first, we'll probably get stand-alone controllers speaking to the mothership powertrain control module (PCM). Mr. Piccirilli says, however, that the control function could be integrated into the PCM — and likely will be when these systems are designed into future all-new engine programs. Judging from its diagram here, Bosch, already strong in development of PCMs, apparently plans to skip the stand-alone controller phase.

Nobody's talking price yet, largely because we won't see production systems until at least the '04 model year. That's when Visteon's first system hits the streets and, coincidentally, also is when Bosch says it will launch its system.

Meanwhile, Mr. Hollis, who happens to have derived most of his development expertise in cooperation with Jaguar, says Jag will use a system for '05 — it's just not clear whether it will be one that Mr. Hollis helps shepherd to market. He's under no illusions: the big-boy suppliers — with systems of their own already in development — appear to be well-placed to burn rubber on the man who for nearly two decades has been manipulating pieces of the electronic engine cooling development puzzle.

“Everybody will infringe on my patents,” he philosophically submits. “I can't count how many hours I've spent on it. But I'm not in it for the money. It's been fun and it's (EETC development) the last thing I'll do (as a full-time professional).” He says he hopes to next year publish a Society of Automotive Engineers (SAE) paper on what he believes remains the sole missing ingredient: how to derive the optimum engine temperature that constantly balances the myriad requirements of fuel consumption versus output of various emissions. He's working with Jaguar now to confirm initial data in this regard.

Aside from the unquestionably meaningful advance electronic engine temperature management promises, it will be as interesting to watch the process of bringing the systems to production — and whether a single, devoted engineer ultimately fits into the plan.

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