Engine Technology

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1,904
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Bay Area, CA
There have been so many changes to engines over the past 20 years. It seemed like there was not much else to develope. We have had: -Computor controlled fuel mixture and timing -distributorless ignition -variable intake -variable valve timing -Direct Injection All amazing stuff. What is next?
 
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2,698
Location
Silicon Valley
SAAB was working on variable compression ratio (a hinged cyl head) and a sparkplug-less, variable spark gap engine (had a protruding electrode as an extension of the piston). I suppose these will enable real fuel flexibility. I won't be satisfied until engines use the same used vegetable oil as lubricant, coolant, AND fuel. No more oil and coolant changes. We'll see this before we see electric cars.
 
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3,094
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Metro Detroit
Also add cylinder deactivation to the list too. I agree with 55 that electrically operated valves are probably coming in the not-too-distant future. I would venture to guess that various types of waste heat recovery devices will start coming to market.
 

Kestas

Staff member
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13,946
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The Motor City
I agree that some type of infinitely-variable valve timing would be the next leap to optimize the engine. I've also read about variable compression technology being developed. This doesn't sit well with me. I think engines are complicated enough. Variable compression would be a nightmare to fix if something went wrong, and would put engine rebuilding as a thing of the past because of the expense.
 
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22,188
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Colorado Springs
Definetally infinitely-variable valvetiming. BMW just about has it now and the motors that have it don't even have a throttle anymore; the valves and associated variability in lift, timing, and duration act as the throttle.
 
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9,448
Location
USA
F1 has been playing with pnuematic and electronic servo's/solinoids that actuate the valves for a long time. If you get rid of cam shafts with fixed profiles the opertunity open up a lot! You also get to reduce valve spring pressure to next to nothing. The spring is their mostly as a fail safe. Plasma injection is also on the drawing board to replace spark plugs.You would have a pre-ignition chamber that holds and generates a plasma charge that is then injected at the right time into the cylinder.
 
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43,658
Location
'Stralia
In the 1920s, Sir Harry Ricardo was building engines with carburettors, low compression, intakae charge preheating, and achieving Brake Specific Fuel Consumption figures below 0.45lb/hphr. With materials and fuel improvements, we've increased the power density of engines...and are still struggling to achieve 0.45lb/hphr (in general).
 
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3,070
Location
Cincinnati
I think once they figure out how to cheaply make fuel cells split the hydrogen in water into power rather than pure hydrogen gas/liquid, that will eliminate regular gas we use today. But so far, it's still too expensive.
 
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267
Location
Idaho
quote:
Originally posted by Shannow: In the 1920s, Sir Harry Ricardo was building engines with carburettors, low compression, intakae charge preheating, and achieving Brake Specific Fuel Consumption figures below 0.45lb/hphr. With materials and fuel improvements, we've increased the power density of engines...and are still struggling to achieve 0.45lb/hphr (in general).
Yup. Allis-Chalmers (and others) built FARM TRACTORS in the 1950's that equaled present-day fuel economy per hp/hr. Someone mentioned the CVT. Not so new either, since Henry used it on the T-Model almost 100 years ago. We've come a long way, baby [Big Grin] Joe
 
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2,387
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Chicago area
It seems that the latest step has been to increase the weight and complexity of compact cars, and to try and maximise the total number of SUVs on our roads.
 
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936
Location
Pittsburgh,PA
One thing negative to all this is it has nearly made shade tree mechanics a thing of the past. I am only 22 but I have talked to guys that I knew since I was a tiny little man and they were always working with their cars. Now most of these guys are nearly seniors now and for the most part have newer cars. I asked a couple I know why they dont work on their cars anymore and they tell me, "cuz I cant, the thing is nearly impossible". Computer control although great for efficiency and performance(generally) has killed alot of the ability to self disgnose a problem and fix it. I envy them cause they got slick new cars, and they told me they wish they had an early 90s like mine since most of the stuff was able to be easily worked on without computers. Even the thing I am currently doing, rebuilding a 3 speed auto tranny is simply since its all hydraulic. The more modern replacement for this transmission was the electronic 4 speed A604. That is near impossible to rebuild without professional diagnostic gear. Mine can be rebuild with simple shop tools. Since this trend toward more electronic controls and computer commanded systems isnt going to stop I just hope the diagnostic tools needed become simpler and most of all cheaper to buy. Or hey, maybe the computer science degree I am working on will serve me well when I am 35 and need to do an oil change [LOL!] Heck I will still have bottles of SLOB on hand at that time I bet!
 

NJC

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3,007
Location
Vancouver BC
quote:
Originally posted by Chris Meutsch: I think once they figure out how to cheaply make fuel cells split the hydrogen in water into power rather than pure hydrogen gas/liquid, that will eliminate regular gas we use today. But so far, it's still too expensive.
You're thinking of onboard electrolyzing although I doubt it exists (too much of a parasitic). There's onboard reformers for fuel cells but the industry seems to favour using compressed hydrogen. For auto FC's, I think this is to reduce complexity of the system. Until they can find an alternative to platinum as a catalyst (~$1200USD/oz..?) and produce a pure grade of hydrogen cheaply and cleanly, it's going to be awhile before we see auto FC's. Fuel cells work, and progress is being made but as per above (among many other variables), some key pieces of the puzzle need to be addressed. My opinion..
 
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4,478
Location
Southern California
quote:
Originally posted by Lazy JW: Someone mentioned the CVT. Not so new either, since Henry used it on the T-Model almost 100 years ago.
Thanks for the interesting history lesson. Hmmm... I seem to recall reading that the Model T used a planetary transmission that only required the use of the clutch when starting from standstill. Thereafter, the finite forward gear ranges were engaged by releasing and engaging brake bands. When automatic transmissions were under development, the initial expectation was some means to automatically shift gears in a modified traditional sliding-gear box with either an automatically applied clutch or a fluid coupling to mate engine power to the tranny. GM got the bright idea to resurrect Henry's planetary gear box idea, attach it to a fluid coupling, and use hydraulics moderated by a valve body to control shift points under load and speed. Hydra-something-or-other - too bad the idea never caught on... [Wink]
 

Winston

Thread starter
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1,904
Location
Bay Area, CA
quote:
Now most of these guys are nearly seniors now and for the most part have newer cars. I asked a couple I know why they dont work on their cars anymore and they tell me, "cuz I cant, the thing is nearly impossible".
It is not impossible. Things are just different. Also, 100k tune-ups are now common. So, there just is not much to tinker with in between. Other than coolant and oils. [Smile]
 
Messages
12,385
Location
Northern CA
quote:
Originally posted by Lazy JW: Yup. Allis-Chalmers (and others) built FARM TRACTORS in the 1950's that equaled present-day fuel economy per hp/hr. Someone mentioned the CVT. Not so new either, since Henry used it on the T-Model almost 100 years ago. We've come a long way, baby [Big Grin] Joe
Model T had a two speed planetary transmission, about as far from a CVT as you can get. The 1909 Cartercar did have a CVT. http://www.histomobile.com/histomob/tech/2/83.htm So did the Sears car (yes, that Sears) and several others in 1909. There is a 1909 Sears with CVT in amuseum near where I live, as well as alight duty farm tractor from about the same time. CVT (aka friction drive) trnamissions of that era typically got about 2000 miles before they needed new friction material in the transmission. CVT tranjsmission using variable diameter pullys and metal belts were tried in the 1920s. AFAIK, none got to production. The materials and lubricants weren't there yet. Your old tractors wouldn't have come close to a modern engine in lb/hp hr under normal driving conditions. If they were gasoline engines, they wouldn't have been as good under any condition. care to post some numbers from a reliable source?
 
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