E85 vs E10(gas+10%ehtanol)

[roosterk0031]

Unless a preformance car where recommened 91, all other are 87 that I"ve ever seen, continue up the E level, been to over 50% in the Cobalt just fine, at 60+ got a CEL. Never went that far with my other experiments. Which car are we talking about doesn't the 3.5 come in a FFV version.

[ksa8907]

Higher intake temps will reduce power and increase knock.

Both our engines are non ffv.

My car is a bit of a special case, it is a sohc 3.2 but the computer thinks its a dohc 2.7. I've always had light knock around 3200-4600 rpm. But now with a grill block I get knock all the time if I push it past 3k and 30% load. I'm hoping e20 will solve my problems. Will have a fill up soon.

[ksa8907]

Update:

So I have ran two tanks of ethanol blends and both are spot on 29mpg, still need to update my fuel log. The results are a bit of a wash, the first tank I got big eyes at the extra torque and had a bit too much fun, but even 29 is higher than it should be with that much racing around. First tank was at e14.5

The 2nd tank I spent half of driving at 70-75 as I was running late for a business meeting in chicago. Second tank was at about e25.

On my third tank now, e20, I'm trying to take it easy, I should be able to pretty easily beat my all-time high of 30.75mpg.

[Frank Lee]

Knock knock. Any knock?

[ksa8907]

Yes still some knock, though only when the engine is heat soaked and intake temps up around 140 with WOT, explains why I didn't get higher mileage. Even with some knock still MUCH less than with 87 octane e10. I think ill try an e40 blend and if that can't cure the knocking ill probably just get rid of the wai.

Just remembered something, my last set of plugs I put in I ground away at the ground strap to reduce shadowing? or whatever its called. The shape is about like a standard screwdriver viewed from the side. but I had a thought, what if at higher temps the skinny ground strap starts getting hotter than normal and that is what is causing pre-ignition.

Fuel log is up to date.

[Cobb]

Shouldnt the mpg be higher? I mean mpge. If you are filling up winter blend e85 which is e70, 10 gallons from empty. Thats 7 gallons ethanol and 3 gasoline. So lets say my insight gives 40mpg on the mid or 400 miles after burning this tank. Shouldnt my fuel economy really be expressed as 133 MPGe?

BTW, I added 4.5 gallons of e85 to my insight, bumped the mpg 5mpg on my leg home. This was in sport mode cycling through the ratios as a switches lanes, passed yellow lights and kept pace with traffic.

[Frank Lee]

Didn't you get the memo? Ethanol is horrible, horrible stuff. It destroys your vehicle, steals money right outta your wallet, consumes more energy than it gives, it destroys the water table, and it TAKES THE FOOD RIGHT OFF OF LITTLE CHILDREN'S PLATES! Won't you think of the children?!?

[Allch Chcar]

Originally Posted by Cobb

Shouldnt the mpg be higher? I mean mpge. If you are filling up winter blend e85 which is e70, 10 gallons from empty. Thats 7 gallons ethanol and 3 gasoline. So lets say my insight gives 40mpg on the mid or 400 miles after burning this tank. Shouldnt my fuel economy really be expressed as 133 MPGe?

BTW, I added 4.5 gallons of e85 to my insight, bumped the mpg 5mpg on my leg home. This was in sport mode cycling through the ratios as a switches lanes, passed yellow lights and kept pace with traffic.

No, do not calculate MPGe for Ethanol blends by ignoring the Ethanol content. Ethanol contains 66% of the energy content of Gasoline per gallon. So to get the MPGe you divide the Ethanol % by 66%(multiply by 1.5) then add in the Gasoline %. That will give you a correction factor to multiply your MPG to get MPGe. Check the wiki for MPGe if you're confused about this.

[roosterk0031]

My Cobalt seems to like a E30, last 4-5 tanks have been E30 with average of 33-34 mpg, but temps were in single digits to -20. Current tank about half gone with normal driving temps 20-40 I'm over 37 mpg indicated, last year same time with E10 was 38-39, but have winter tires this year vs LLR last winter.

[Cobb]

Ive been watching the show moonshiners. Ive considered the idea of making my own ethanol to mix to my fuel thus recycling my garbage. Otherwise I supplement my gas use with coal and the tears of children.

Originally Posted by Frank Lee

Didn't you get the memo? Ethanol is horrible, horrible stuff. It destroys your vehicle, steals money right outta your wallet, consumes more energy than it gives, it destroys the water table, and it TAKES THE FOOD RIGHT OFF OF LITTLE CHILDREN'S PLATES! Won't you think of the children?!?