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19 hours ago, LittleBlue! said:

I'm learning as I go but if you increase compression you can benefit from the octane in the ethanol. I'm going to try and add a turbo from a sonic to increase the compression.  There is an interesting test with a Cadillac and Ford fiesta. They tinkered with turbos and saw great results with mid level blends. I'll post the link here.  

2018-03-03 02.06.56.png

 

 

Stil didn't answer my question.  How is mpg going to increase?

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Posted (edited)

 Search octane and high compression ethanol has higher octane you can run on higher compression and more efficiently. Read the source and research more. The above text highlighted is dirctly on point to your question.  Look up E85 turbos and high compression. 

 

https://www.carthrottle.com/post/engineering-explained-high-vs-low-octane-petrol/

 

By using a high octane fuel, engine designers are able to implement various techniques to improve reliability, efficiency, and power output. First, it helps prevent knock. Engine knock, or pinging, occurs when a separate pocket of air-fuel mixture ignites after the spark has ignited the air-fuel mixture within the combustion chamber. This is obviously undesirable as it can cause serious engine damage, and it can be prevented by using the proper octane rated fuel.

Second, higher octane allows for the use of higher compression ratios. Compression ratio is directly linked with thermal efficiency, so the higher the compression ratio, the more efficient the engine will be (law of diminishing returns certainly applies).

These are my thoughts:

E30 has "less energy"  but the 101 octane allows for  higher compression without knock and more fuel efficiency, if tuned properly. The spark is at 10.5:1 (or close) and a turbo with low psi could increase that a bit and you can take advantage of the 101 octane in E30, which is actually cheaper than 87, by quite a bit.

Edited by LittleBlue!

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Anything is possible for the right price. In the case of a turbo, might be cheaper and simpler to just do a trade-in for a faster car. Compression at 10.5 for the Spark means the valves are already very close to the piston at TDC..a costly head shave and a change to VVT and sensors, reprogram the ECM would maybe give you an xtra 0.5 compression..still too high for all but a very low end turbo and a huge cost thus offsetting any fuel savings...but like I said in a previous post...anything is possible for a price. Just not practical and I would not like to drive with such a small valve clearance...specially at higher RPM's...

LittleBlue! likes this

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Thank you for the feedback. Like I said, I'm learning as I go. I got this car cheap and I'm passionate about ethanol. I'm hoping the high octane may allow for compression that would not be possible otherwise. Here is an interesting article on E85 and effective compression ratios if you are curious why I think I can get away with this 

http://www.onallcylinders.com/2015/11/20/ask-away-with-jeff-smith-what-is-safe-effective-compression-ratio-for-e85/

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Interesting article Blue...Just want to say, and have said in previous posts, that I always have a lot of respect for people who are willing to do the research and work themselves. You learn something and get some hands on experience..learn as you go..just don't make the car blow...'Nuff said....

LittleBlue! likes this

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Posted (edited)

Giving credit to blue.  I used to be one of those guys that wanted to get most power out of everthing.  Dumping money into a pointless cause. Now i enjoy it as it comes and dont mess with it.  But i will not discourage anyone from trying.  

Edited by Splash Spark

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