If this has been asked and discussed previously, just say so and we'll move on. Can old high performance (300 HP and higher) corvettes to use E-85 or 100% ethanol? What modifications would have to be done or is it impossible? I also know that it may not be practical. However, if the cost of gas continues to rise, a lot of people in our hobby will be impacted.
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Re: Using Ethanol
Pat-----
I've thought about this quite a lot but only as an "academic exercise" and not for any plans I have for practical application. I think it could be done without a lot of trouble. Actually, I think it would be easier in these old cars than converting a modern car. The changes that I think would be necessary would be as follows:
1) replace rubber fuel lines at tank and at pump with lines compatible with E-85. This should not be too hard to obtain;
2) replace fuel pump with pump with internal parts compatible with E-85. I don't know where one would get such a mechanical pump. However, conversion to electric ought to offer sufficient choices;
3) re-jet carburetor to accommodate the lower BTU value of E-85. Also, change gaskets and seals in the carburetor to be compatible with E-85. I don't know where such parts could be currently obtained;
The following MIGHT be necessary:
1) replace metal fuel lines. I really doubt this would be necessary as I think the existing lines would last longer than any of us are ever going to need them to even with E-85;
2) replace carburetor with a unit that's designed and optimized for E-85. I don't know where such a carburetor could be currently obtained.
That's it! However, I don't think that 100% ethanol would be practical, although it might be possible to make such a conversion.In Appreciation of John Hinckley -
Re: Using Ethanol
Edelbrock is now selling a E85 600CFM carb designed for ethanol.
Most of the carburetor info I have seen emphasizes the high octane value of E85 but fails to mention the lack of efficiency as compared to gasoline.
Google E85 or ethanol carb for more info.Comment
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Bruce-----
I wouldn't really say that E-85 lacks efficiency relative to gasoline. E-85 or pure ethanol have less BTU value per unit volume than pure gasoline. So, it takes more unit volumes to get the same amount of energy as equal volumes of pure gasoline.
Diesel fuel has MORE BTU value per unit volume than gasoline. That's ONE of the reasons that diesels get better MPG than gasoline.
A barrel of oil only has so many BTU's in it. When it is fractionated through the refining process, the sum of the BTU value of the products made from a barrel cannot equal more than BTU value of the original barrel of oil. So, someone who buys diesel fuel is actually getting "more" of that original barrel of oil than someone who buys an equal volume of gasoline.
I think the above is ONE of the reasons that diesel has risen in price relative to the price of gasoline. In effect and in rational terms, diesel was "underpriced" compared to gasoline for years.
Smokey Yunick said about 20+ years ago that diesel fuel ought to cost more than gasoline. Others finally figured that out.
Ethanol cannot, of course, be compared to gasoline or diesel in a similar relationship since it's not derived from oil.In Appreciation of John HinckleyComment
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Hey Wait A Moment. I'm confused. Here In Florida, our pumps say E90. A sticker below says "may contain up 10% ethenol. (sp). To me, that means 90% gas and 10% of the corn stuff. Where are they selling 85% ethenol? I think your #s are off. Does E85 mean it's 85% ethenol? I don't think so. Bill.Comment
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Bill-----
I've never heard of E-90; it may be some sort of local nomenclature. If it is, it's no doubt causing confusion.
E-85 is a mix of 85% ethanol and 15% gasoline. Period. The "E" represents "ethanol" and the "85" represents the percentage of ethanol in the fuel. This fuel is available in certain parts of the country, but you won't find it at every gas station in those areas. In other areas, it's rare on non-existent. In California, it's around but extremely rare.
If this "E-90" fuel you're talking about is a fuel that you can run in most vehicles, then it's obviously not 90% ethanol and 10 gasoline (I know of no such formulation, anyway). What it must be is a formulation of 90% gasoline and 10% ethanol. That blend is widely available throughout the US since the phase-out of MBTE. In California, much fuel is 15% ethanol. That is the highest percentage of ethanol that's approved for use in most of the cars manufactured by major auto makers EXCEPT those described as "E-85 capable" or "Flex Fuel".
For GM cars, many of those equipped with the 3500 V-6 are "Flex Fuel" and can operate on pure gasoline, E-85 or any blend of ethanol and gasoline between those two. Some other GM engines are Flex-Fuel, too, but the mainstay right now is the 3500 V-6.In Appreciation of John HinckleyComment
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Thanks fellows. I saw a session on Fox News about a unit that is coming out for sale that produces ethanol. It looks like an oversized gas pump. It works on a sugar/yeast mix plus water and produces 35 gallons per week. You can see more on this unit at www.efuel100.com
After I reviewed the website, it struck me that this unit is nothing more than a small version of a whiskey still. In my part of the country (South Miss) I have lots of friends/relatives who are experts at making stills and making whiskey. Soooo, making ethanol is not a big problem. Even securing a Federal license to produce ethanol is not a problem. I can make the calculations to determine whether it is economically feasible to make the ethanol. However, more importantly, is to figure out what is required to use 85-100% ethanol in old vettes and other vehicles.
With the high cost of gas and no end in sight, I think this is the kind of discussions that are needed in order to insure that we all can continue to enjoy our hobby. I'd like to hear more from everyone. Emails are okay.Comment
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Bill,
As Joe noted, E90 would be 90% ethanol, which is not a fuel currently available. E10 is a more typical formulation, and is the 10% ETOH that most of us get at the pump.
From what I understand, building a high performance car that is dedicated for E85 or greater is very similar to a drag car running methanol.
JoelComment
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Don't need to look too far on this one. The web site for the still states quite clearly that 10-14lbs of sugar are required to make one gallon of ethanol. Retail price of sugar is around 45 cents a pound so simple math makes this cost INeffective without considering the energy consumed to run the machine.
Widespread use of these machines would simply cause the price of sugar to skyrocket.
Why don't you guys just get your government to drop the import tax on ethanol?
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A number of guys in the Camaro side of my hobby have done the complete conversion to E85-capable, several of which are pretty much strip-only cars. There's a LOT more to an E85 carburetor than just jetting and ethanol-friendly gaskets and seals - it also requires major alterations to the needles and seats, air bleeds, emulsion chambers, power valve channel restrictions, etc., and these carburetors aren't cheap - around $800 for one that's done correctly, and each one still has to be tuned/calibrated to the individual application before they run right.
The other thing to remember is that on a carbureted car, once you make the conversion, there's no going back - you CANNOT ever run normal gasoline again without changing the carburetor and re-tuning, so you can't drive beyond the range of the nearest E85 station unless you carry the parts to convert back around with you all the time.Comment
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Re: Using Ethanol
Given enough knowledge, time, and money anything is possible, but even with the current subsidies on ethanol the cost per BTU is not that much different than gasoline, and without subsidies ethanol would be more expensive per BTU than gasoline.
Unless you're an experienced fuel systems engineer or can afford to hire one or buy a properly engineered and tested "conversion" (assuming such exists) continue to use gasoline.
Given the typical rate that vintage Corvettes accumulate mileage, ethanol is an economic loser, and "backyard engineering" conversions are likely to throw you into a black hole.
If you want to reduce energy costs, the first place to start is seriously looking at your daily driver vehicles and consider replacing them with something lighter and smaller.
A friend who has a large property that requires a lot of yard work drives and mid size pickup truck to work (110 mile round trip) because he needs a pickup to buy mulch, etc. His wife drives an Acura MDX, and he has a Honda S2000 for fun.
I've suggested that he buy a Honda Fit or something similar for the commute, off the pickup and buy a utility trailer for the MDX. He's seriously considering it.
Some have lauded the improvement in "efficiency" by raising the compression ratio. (Ethanol has about 105 PON.) The theory is true as the Carnot efficiency is a marginally decreasing function of compression ratio, but you are looking at a major engine rebuild, and at best you can raise the CR to something on the order of 12.5:1, which will yield a 5 percent improvement in fuel ecomony relative to 10.5:1. An increase from 8.5 to 10.5 is worth about 10 percent. That's what "marginal decreasing" means. Each increment of CR increase yields an ever decreasing increase in efficiency.
Beyond 12.5:1 the combustion chamber begins to exhibit unfavorable geometry effects (such as a high surface area to volume ratio that transfers heat away to fast), so improvements due to increased CR beyond about 12.5 requires a completely redesigned combustion chamber.
A lot can be done to improve fuel economy of vintage engines. For example, most engines get rebuilt with high overlap cams and low compression, both of which combine to reduce fuel economy and torque bandwidth. The "Special 300 HP" configuration I developed has high CR (10.25-10.5) combined with a special design low overlap cam with a late closing inlet valve along and retuning the spark advance map to the ragged edge of detonation under all operating conditions.
The result is SHP top end power with only a slight loss of end torque and equal or better fuel economy to the OE configuration and no visible change in appearance or idle quality compared to an OE 300 HP engine.
Given the typical 20 cent per gallon price differential between premium and regular unleaded at the four dollar level the increase is only five percent, but raising CR from 8.5 to 10.5 will increase average fuel economy up to 10 percent, so at worst it's breakeven, but the engine will have more torque/power across the rev range.
Given the current paranoia over energy costs, I wonder how long big blocks will maintain their lofty values. Back in late seventies - after the second "energy crisis" - you couldn't give them away! I think base engines with their relatively good inherent fuel economy and relatively tall gearing are going to see a renaissance, especially to those who understand their performence/fuel economy potential with some well thought out system engineered changes.
DukeLast edited by Duke W.; May 19, 2008, 01:03 PM.Comment
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Re: Using Ethanol
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Re: Using Ethanol
Pat emailed me about this "home ethanol station". He heard about it on Fox News, and I saw that Clark Howard mentioned it as I read his Web site, today. He mentioned an article in The New York Times... some of you can probably fill in my thoughts from here.
www.efuel100.com/
Using their own data, 13 pounds of sugar will make one gallon of ethanol, and the "station" can make 35 gallons of ethanol per week. This will fuel two 13 MPG mid to full size vehicles for about a week at 450 total miles (remember that E85 MPG is about 70 percent of E10).
You will also need some yeast and a non-trivial value of electrical power plus about 5 gallons of water per gallon of produced ethanol.
First you will have to hump 450 pounds of sugar a week from your supplier, so you will need a pickup truck.
I googled "raw crystalized sugar" and found one supplier who offers 50 pound bags for about $75. This is food quality product. Maybe there is "industrial quality" product that is cheaper - I don't know, but using a $1.50/pound the raw sugar cost is nearly $20 per gallon of ethanol exclusive of the yeast and electrical power, so I don't know how they come up with their $1/gallon unless you can buy raw sugar for about a nickel a pound. I don't know of any commodity you can buy for a nickel a pound.
The numbers just don't add up, and the mass media is too lazy or too stupid to do a simple analysis using some basic chemistry and economics.
DukeLast edited by Duke W.; May 19, 2008, 05:20 PM.Comment
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Duke,
What you say makes complete sense for daily driving. We all need to reevaluate what where and how we drive. My job (outside sales) puts 25,000+ miles on my car each year to see accounts / close and support sales. And what I drive has always been a consideration as to safety and costs.
But for our pleasure machines, would the course we should consider be to look at what you describe, the next time one needs an engine overhaul?
Another point, in addition to making the engine more efficient, what about the transmission? Most of my Corvette driving are pleasure rides, and I have wondered about possibly swapping out the THM400 for a trans with an overdrive to keep the revs down.
Now I know that doing something like that now becomes an issue of changing the original factory configuration, but at some point we may have to decide what's the reason we even own these cars, to have fun driving them or to have an original piece of production sitting in our own "museum".
Do you know of anyone doing a trans swap and if so, what mileage increases they may have gained?
Save the Wave,
Bob RicchioComment
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Re: Using Ethanol
An overdrive transmission will increase highway fuel mileage 5-10 percent, but how many road trips do you take? There would be little effect in around town driving.
Typical vintage Corvettes run few hundred to a few thousand miles per year, and in the overall scheme of things, fuel is not that big a cost. A thousand miles a year at 15 miles/gal and four bucks a gallon is less than $275.
However, if an engine rebuild is on the horizon, taking steps to maximize engine efficiency adds little or no cost to the job.
Think about guys with airplanes and boats. Even if rarely used the fuel costs add up a lot faster than a vintage Corvette.
DukeComment
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