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Old 10-03-2013, 12:54 AM   #171 (permalink)
Allch Chcar
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Join Date: Jan 2008
Location: North Coast, California
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Cordelia - '15 Mazda Mazda3 i Sport
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Originally Posted by Old Tele man View Post
Sorry, but my data indicates that "Flex" engines not incorporating turbochargers (to yield variable-compression ratio operation) have been LESS efficient...only those engines capable of operating at higher CR can effectively "use" the higher octane value of E85 and so advance timing to produce more HP...but NOT better fuel economy, ie more distance per gallon.
False, flexfuel engines have been advertised as making more power on Ethanol since they were introduced. 99% of them are Naturally Aspirated and have exactly the same compression ratio as their non-FFV versions to allow for efficient operation on Gasoline.

Originally Posted by Old Tele man View Post
True in "short-duration" operation for diesels (CI), but not under continued long-duration operation because gasoline/alcohol 'solvent' is damaging to injectors, because the injectors rely on diesel for lubrication...which E85 lacks. The new gasoline direct-injection (GDI, SIDI, etc.) engines will 'test' the quality & durability of new piezo-injectors with gasoline AND E85.
False, long term reliability studies show little to no degradation with Ethanol. I have only heard anecdotes of fuel injectors clogging due to Ethanol picking up crap from the fuel tank. But never outright failure of fuel injectors. Piezo injectors aren't used in everything. Ford is using cheaper units for their DI FFVs.

Originally Posted by Old Tele man View Post
Current EPA regulations effectively dictate SI "closed-loop" engine operation at stoichiometric (~14.7:1 A/F) because of the catalytic convertors; hence, the days--and discussions--of "lean-burn" operation is meaningless.
I was referring to Diesel Engine operation a.k.a Compression Ignited Engines. I apologize for the confusion.

Originally Posted by Old Tele man View Post
At one time the industry 'standard' was 8-hours driving at 50 mph, or 400 mile range, per tank...with tank "capacity" being 'sized' to achieve that range (roughly). Today, the 'standard' is more like 8-hours at 65 mph, or 520 miles expected range. And, since "fuel" is sold by volume, it isn't surprising that some people WANT as much range from each gallon they pay for as possible. It's called being 'conservative/frugile' rather than being 'extravagant/wasteful.'
It's called being penny smart and pound foolish. You give up something of minor benefit now to lose out on a greater gain in the future.

-Allch Chcar

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