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xcel
03-06-2006, 12:37 PM
Japanese manufacturers constantly refine their conventional engines. (http://www.sae.org/automag/techbriefs/03-2006/1-114-3-20.pdf)

SAE Tech Briefs - Jack Yamaguchi - March 2006

http://www.cleanmpg.com/photos/data/501/Resize_of_Honda_Civic_1_8L_ICE.jpg

Although hybrids have gotten much of the media attention recently, Japanese manufacturers have been constantly refining their conventional engines. Here are some worthy of note.

The R18A 1.8-L i-VTEC inline four cylinder engine is Honda’s global inline four, first introduced in the new Civic range. Intelligent VTEC technology is employed in the engine to vary intake charge volume. Unique to the 1.8 i-VTEC engine is that the FE (fuel economy) cam, engaged during low-load operations as steady cruise between engine speeds of 1000 and 3500 rpm, delays the intake valve closing timing by 63° (94° ABDC) vs. the HO (high output) cam (31° ABDC). In FE mode, the engine operates in the adaptive Atkinson cycle, taking full advantage of the superior fuel economy by greatly reducing pumping losses.

The R18A engine produces 103 kW (138 hp) at 6300 rpm and 174 N•m (128 lb•ft) at 4300 rpm on a 10.5:1 compression ratio, and is content with regular grade unleaded gasoline. The output is 7 kW (9 hp) and 19 N•m (14 lb•ft) higher than the previous 1.7-L VTEC unit. More significant is an increase of 22 kW (30 hp) at the frequently used 3000-rpm zone, greatly enhancing on-road performance. On fuel economy, Honda cites a 6% improvement over its predecessor.

VCM is the acronym for the variable cylinder management technology that deactivates one bank of onda’s J30A 3.0-L VCM V6 engine. The engine powers Honda’s upscale models including the North American Odyssey minivan, the Japanese Elysion minivan and Inspire sedan, and is combined with the IMA hybrid system in the U.S. Accord Hybrid.

The VCM V6 is still the only one of its kind, and its switching between full-six and partial-three cylinder operation is almost imperceptible, thanks to the active engine mount system and acoustic noise suppression.

In the North American-exclusive Accord Hybrid, the SOHC four-valves-per cylinder, 2997-cm3 engine produces 190 kW (255 hp) at 6000 rpm and 315 N•m (232 lb•ft) at 5000 rpm on a 10.5:1 compression ratio, combined with the 12-kW, 136-N•m (100-lb•ft) - at 840 rpm – electric motor, and driving the front wheels via a stepped-gear, five-speed automatic transmission. EPA mileage estimate is 29 mpg city and 37 mpg highway, vs. the gasoline-engine-only Accord EX V6’s 21/30. VCM accounts for about 15% of the improvement in fuel consumption in city mode, and as much as 57% in the highway mode.

Daihatsu’s new Topaz KF is unlikely to find its way outside of its home country, Japan. However it is significant that the mini- and small-vehicle specialist has pursued and achieved its objective of a low-mass, low-friction, fuel-efficient, mini car engine. The aluminum inline three-cylinder engine displaces all of 660-cm3, the Japanese light vehicle limit, and produces 43 kW (58 hp) and 65 N•m (48 lb•ft).

The Super Intelligent three-way catalytic converter cleanses exhaust gas from the Topaz KF engine. The catalyst is the latest development of the Intelligent Catalyst that was first adopted in Daihatsu’s light cars in October 2002, and the aggregate number of units installed now exceeds 1.5 million. The Intelligent Catalyst can regenerate one of its precious metals, Palladium, as well as greatly reduce the amount of all three precious metal contents.

The Super Intelligent Catalyst further reduces precious metal contents, by 50% vs. the Intelligent Catalyst, and 70% vs. the conventional three-way catalyst, according to Daihatsu, and it now regenerates the other two precious metals, Platinum and Rhodium. Daihatsu, Japan Atomic Energy Agency, Hokko Chemical Industry, and Cataler have jointly conducted the Super Intelligent Catalyst research.

psyshack
03-06-2006, 01:06 PM
Theres my R18A. Time will tell about this motor

philmcneal
03-06-2006, 01:33 PM
i wish they done analiysis of toyota's motors too! But i never knew teh r18a acts like an akitiston when its under low load. Impressive Honda having "the best of both worlds" under his belt.

Efficency and fun.

cleverlever
03-06-2006, 05:31 PM
i wish they done analiysis of toyota's motors too! But i never knew teh r18a acts like an akitiston when its under low load. Impressive Honda having "the best of both worlds" under his belt.

Efficency and fun.


A real Atkinson purist would be embarrassed by a 10.5 to one compression ratio. Its really late intake valve closing to reduce pumping which is only half an Atkinson engine.

psyshack
03-07-2006, 06:47 AM
Driving a car with this engine in it. Is tricky. I look at the low load cycle in terms of 1500 rpm to 3000 rpm. There is nothing useable below 1500 rpm. It becomes a lug fest below 1500 rpm. I really need to get a manuel for this car and engine. At 3500 to 7000k rpm it wants to run but is hampered by the absence of a exhaust header. Basicly dumps right into the 1st CAT. I must say Im leary of this no exhaust manny and that huge CAT. If this car gives me any CAT problems it will be gone faster than a bent penny. It is kind of a jumbleing together of two or 3 diff. engine designs and thought patterns.

Take its lateist tank. I drove it 181 miles never going over 65 mph with much of the driving at 60 mph to 45 mph. Alot of FAS, Coasting, Load driving, Stop light engine shut offs, Tires at 40+ psi,,, hypermiling over all. Net 42 mpg.

I have a trip to take in the car today into NW Arkansas. 90% HWY and Im going to HM it all the way to the best of my ablitys. This little day trip is for work so I do have to focus on getting there and getting the job done! Speed limits will vary from 25 mph to 75 mph. With 4200 miles plus on the engine it will be nice to see what it will do running below posted speed limits and useing FAS, Coast, some surfing and steady speeds with load driving. I wont P&G. Thats just a plain pain in the arse. The over all tatic will be to keep the engine in the low load range of operation. And let it sip fuel and make my trip a longer one. The best way to do this trip is on the main Hwy's and turnpike. Trust me,,, you dont want to use the two lane's and the many small towns one has to go thru.

So with that,,, im off to put some miles on my R18A with its fresh crank case of M1 5w-20 and see what it will do.

psy

cleverlever
03-07-2006, 09:02 AM
Re low speed torque loss in Honda's R 18 A engine.

Please read this link http://modifiedatkinsonatkinsoncycleengine.blogspot.com/

Makes you wonder why Honda doest just alter the compression ratio and reprogram their i-VTEC mechanism to make a winner out of a loser.

Feedback would be appreciated.

psyshack
03-07-2006, 09:08 PM
Todays driving is over,,, thank god. The yeild was 45 mpg. It appears that I ave. 52 mph. Shifted at 2k rpm. Never got above 3k rpm. stayed in the right lane and didnt pass anybody. Temps started at 53f at 7am. Went up to 75f by 7pm. Wind out of the south at 25 mph with gust to 35 mph. Wind ruined my mpg today. Saw some postering by truckers in Tulsa to cut cars off that deserved it. Drove into a crime sean where a Arkansas State Trooper shot and killed a fugitive from Michigan. And my 200hp electric motor in Arkansas still viberates. All and all a worthless waiste of time day.



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