E85 compression

[thebig450es]

How high can i go on the compression if i switch to e85? will i see much difference keeping the stock bore?

[honda400ex2003]

I would say about 13:1 at least maybe 14:1 since it is 105 or 110 octane i think, steve

[Donjuan400ex]

would it be bad to run E85 on a stock motor with the few mods i have done to mine in my thread?? how would it act on my quad??

[brian76708]

im guessing since e85 isnt as efficient you will need bigger jets to run it.

[thebig450es]

I hear that you need to increase the fuel by about 30%. I've heard people using 230mj.

[Snipe]

My thoughts on E85. Our city came to our international dealership and wanted all there trucks swapped over to E85. After a month everything was rusting out, motors and all. E85 is still pretty new and I personally stear clear of it.

That is only because I know what it can cause and seen what it has done.

[honda400ex2003]

It has a very high alcohol content in it so yes it does need much bigger jets and is corrosive. I also stay away from it even with only 10%. steve

[Snipe]

That is why I wont run Casey's fuel in my truck or ATV as that is why there cheaper they run 10% in there gas. Not for me plus I loose fuel miliage.

Stick with super in the 400ex and reg in the truck you wont regret it.

[Wheelie]

Ethanol is not nearly as corrosive as most people think, Methanol, however is.

I've been running it in my quad for almost 4 months now, not a lick of trouble.

Swapping from gasoline to straight E85 will gain roughly 8-10% horsepower by the fuel swap alone. Jetting does have to be increased by 25-30%.

[Snipe]

But since your running such a massivly larger jet wouldnt you be burning through a tank alot faster?

So in theory here as you have not replied back, since your jet is bigger and your burning more gas wouldnt you just be burning through more "green" fuel instead of less standard fuel?

[honda400ex2003]

Yup. unfortunately. I would not do this mod anyway unless i wanted the extra compression that can be had with the ethanol. steve

[Wheelie]

A tank of fuel doesn't last as long as it used too, but the trade off is worth it.

E85 is 105 octane and 1.60/gal in my area. I used to run mixed premium with race gas 50/50. Race gas was $6/gal for 110. Assuming $3/gal for premium (for easy math)--race gas blend would be $10.80/tank for 2.4 gallons.

With my current E85 blend, it would be about $4.80 tank. Not only do I save about $6 per tank (based on $3/gal gas), but I make more power doing it. Also, the engine runs cooler, the fuel burns A LOT cleaner, and it's a renewable fuel. The exhaust smell actually smells good, really good.

Now I just need to put a corn sticker on my quad.

[Wheelie]

To answer the original question, I wouldn't want to go past 14:1 on E85. I've read people running as high as 15:1 in cars on E85. It has a very high MON rating (fuels resistance to detonation), about 100 IIRC, 110 race gas has a MON rating of about 101.

[thebig450es]

i was thinking of going with a Wesco 12.5:1 . Or what other piston would work?