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Fuel Choice

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If you optimize an engine to run ethanol in the most efficient manner,...

 

 

Ethanol engines will never reach optimal efficiency if they are hampered by the limitations imposed by running gasoline. If you want an apples to apples comparison of the differences in power, drivability, and efficiency between a high compression ethanol engine that would rattle itself to death on 87 octane, and the same size engine with 87 octane capable compression, but with the same cam timing, same intake, same everything else, well you only need to wait until June or July to see the difference. I should have the ethanol engine built by then, the gas one is done already.

 

So tell me-

 

How do I find high compression pistons for something like an HHR 2.4 liter?

 

Or high compression pistons for an even smaller engine?

 

I think I would be happy with an E85 only engine- IF it is small enough to really get decent MPG.    I have the Dodge 2.7 liter now- plenty of power in that- but I would be happier with a smaller displacement and higher compressions, for higher MPG with equal power.

 

That's the dream I'll chase. 

 

So, what is the suggestion 4 cylinder smaller engine (smaller than my 2.7 liter Dodge) that there are high compression pistons out there on the aftermarket?

 

 

 

http://www.rosspistons.com/

http://www.venolia.com/

http://www.jepistons.com/

 

Just a few. They will make anything you want, some engines might cost a bit more but these companies make bulletproof parts. I run Ross pistons in two of my engines, and yes a set will cost around $500 for most V8s. These are not cast or hypereutectics that will break with high compression, and they are not cheap offshore parts either.

 

Another thing you can do to raise the compression with some engines (DOHC is tricky to say the least) is milling the head and decking the block. I have the luxury of having only to swap heads to get 13:1 with a basic flat top piston. Alternatively a larger engine will have higher compression with the same sized chamber in the head, so stroking it with a larger crank can be an option. Dont run dished pistons and the compression goes up, but it depends on how much a stroker kit would cost, and if one is available for your engine.

 

Its nice being able to do most of the work myself too, the only thing I have to farm out is machine work. I do computer tuning, and everything else, I just cant afford the machine tools otherwise I would have them.

 

Remember that if you run only E85 or only ethanol in your engine, the car will likely rust away from around it before the engine wears out. The oil changes will be much farther apart unless you like changing clean oil for the fun of it. So how long do you have to own a car before the cost of the pistons is amortized? It depends on how far you drive and how much you like that engine and how much it costs to change things inside it. I like my engines to last a long time when I build them.

 

I am considering tearing down the 3800 in the Gran Prix we use as a winter beater and replacing the pistons and rods in it, just so I can run ethanol and keep the mileage, of course I want to demonstrate what is possible too so it would be sorta like a demo mule. If there isnt much taper in the bores from the carbon rubbing around on them, you could get by without boring it. Then its relatively simple to press on new pistons, add new rings and bearings, gaskets, and have the crank balanced for the new pistons that will probably be lighter.

 

If cost is the only consideration for anything, then why are you bothering to run E85 if the price spreads arent very big and its a wash in your FFV?

 

I agree the larger problem is availability HF, but it isnt as big a problem in some places such as where you live. It is very annoying to have only one station up here with E85 and it isnt exactly close by either.

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In the 70's, some engines used dished pistons, some bigger heads. If you had the bigger heads (like Pontiac), you could swap in a set of Ram Air heads and get an instant hi-compression engine.

 

I haven't seen the inside of an engine newer than '74 so not sure what they do these days...

 

That is what I am doing, 68cc heads from a RAIII 400 on a 467, or if I go for the extra $500 crank kit that would give me a 496 and around 14:1.

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Ram Air III's are the best bet in my book. RA IV's (better flow, bigger valves) need domed pistons since they have a larger chamber (if I remember correctly).

 

I gave a set (III) away years ago b/c I had no room for them while in school.

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RA IV were still small chamber but had round exhaust ports, HO and SD heads had round ports but were large chamber. RA III were D ports, that means cheap headers.

 

It would be nice if the OE's would give us the option of having ethanol capable compression instead of camel whiz compromised engines. The alternative is to buy an older vehicle and rebuild the engine with the money you save on depreciation. :)

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The E85 ethanol engine option possibility for production autos? Maybe as an after market supplier. Custom vans, some engines, and convertibles were supplied by non automotive manufactures to convert production autos for dealerships. Can you image a Penske E85 engines supply for dealerships? 

 

Actually, I bet engine remanufactures will be first to offer the option. It appears the performance market already their.

 

Another thought for the day.------Do you remember the Detroit Diesel 2 cycles? Well, they had a substantial built in efficiency advantage, but lost the gain to complexity of engine parts. You see the engine had to have a longer stroke as a result a heavier and more complex engine block casting. Also, the engine relied on intake boost pressure obtained by combined super charger and turbo charger. They needed a super charger as under low flow exhaust the turbo didn’t produce enough intake boost. Also, the head parts were under more heat as less cooling effect. This is an interesting read

 

http://www.yachtsurvey.com/comparing_diesel_types.htm

 

What am I thinking…..yes ethanol.  First, ethanol packs more oxygen, so the low speed, low power and ensuing low intake boost not as big a problem. Second, the head cooling easier with hydrous ethanol as compared to diesel fuel. Third, Detroit Diesel had spent $1.5 billion to re-engineer their diesel to conform to EPA regs recently. Ethanol has no such problem with air quality and conformance to air quality standards a low R&D cost. So, the complexity problems of old 2 cycle Detroit Diesel design can be minimized with ethanol fuel? To my thinking this design perfect IC engine for hydrous ethanol. Also, Detroit Diesel sells a DD15 engine with turbo cogen. A hot exhaust turbine capturing free energy and mechanically linked to engines output shaft. A 50hp gain. The 2 cycle hydrous ethanol engine would be a DI spark plug ignition and 4 exhaust vales per cylinder engine and as much turbo boost as possible. 

 

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I see no reason why the below described engine couldn’t easily surpass Ford’s Eccoboost 20% better mileage per horsepower. The 2 cycle should be in the 30% range improvement within the E85 fuel camp. Not near to diesel fuel, but past normal unleaded only engines mileage, especially if you change drive train to match low end torque. Of course that would be an improvement based on optimal E85 engine efficiencies. Meaning when Ford achieved a 20% improvement, that was a comparison made to current highly efficient unleaded engines. Our current crop of E85 flex fueled engines not operating optimal under E85 as you all know (refer to 455).  So, everything else being equal, a very big relative jump for E85 mileage possibility?

 

Also, the 2 cycle engine would be small, sure very strong and heavy for the size as compared to typical unleaded engine, but half the size….much smaller than Fords Eccoboost amazing engines. Ford 3L Eccoboost has more hp than 5L V8….so a back of the napkin calc….a 1.5L 2 cycle equivalent power? So, a high mpg engine in lighter frame auto would only require fractional liter displacement? 

 

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NOW THIS IS WHAT I'M TALKING ABOUT!  (that is me being very LOUD)  ;D

 

Now if the big (well, formerly big) 3 in Detroit will not make these engines, would they ever sell a NEW factory car with NO engine?  Leave it up to the consumer to have a "custom" engine installed.

 

My dad in 1979 bought a stock GMC truck with an underpowered I6 engine brand new, yanked the engine out, and put in a high torque I4 Isuzu diesel... it could out pull most 350s...  but that brand new I6 is STILL sitting in the back of his shop on a block... don't think there is more then 100 miles on it!  With the cost of new vehicles, it doesn't make sense to buy an engine you don't ever plan on using.

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Now if the big (well, formerly big) 3 in Detroit will not make these engines, would they ever sell a NEW factory car with NO engine?  Leave it up to the consumer to have a "custom" engine installed.

This is a little off but there is an outfit called Pittsburgs Power that soups up truck engines. Right now they are pushing a new glider(new truck minus the engine and tranny) kit from Peterbilt and Western Star with a rebuilt engine that bypass's the new emission stuff. The guy says Peterbilt is slow to produce these gliders and Kenworth won't even respond since they only want to sell a complete new truck. Here's a link. Click on "performance zone" when it opens.

http://www.tenfourmagazine.com/

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