I find it safer to tune and add 10% extra fuel to a map thats 1 point lean vs a tune thats 3-4 points lean.

 

So today i filled 7.5 gals of 93 and 2.8 of E85. Added 10% across the entire map. I'm running half a point rich in vac and about a full point in boost...down to 11afr. So i'd assume 5% should be good for a 75-25 mix. It seems to be running smoother and with less hickups.

 

Alrighty just an update, today was my 2nd partial fill up with more E85.

So my 1st tank i started with 5%, ended up adding it to 7% and it ran good. Today almost at empty i filled it with 2 gals 93 and 3 gals E85. I added 7% across the entire map ran rich so i removed 7% to get it to stock then added 5% and its good now.

Keep in mind 7% and then 5% is not just 13% as you'd expect.
1ms x 1.07 = 1.07ms
1.07 x 1.05 = 1.1235 not 1.13 as you'd get by just adding the total from above.

I've had to change boost also as it was running in the 13s so in boost its more like a 15% while in vac its only 12 so its not flat % across the entire map in other words you'll need to rework your map.

Now how the hell are u guys tunning the spark with that juice?

Personally i feel like its running smoother and quieter.

 

I wish Canada would get with the times and bring E85 in.

On a side note, our gas is now E10. If I get it tuned on 91 oct E10, and then run a track day in states with 92 Oct (no E) is it safe to assume I'll be just fine?

 

Gas in the states all has 10% Ethanol content.

 

Oh does it now? I guess they pumps I use in Blaine don't feel like posting a sticker.


Follow up question.. if tuned on 91 E10, running 94 pure should be fine, yes? 94 up here does not have E in it YET.

 

Yeah i was looking at that today, the octane pump does not say 10% ethanol on it however the ethanol pump does say minimum 70% alcohol in it so i dont know.

 

Yeah here in Canada it says on a sticker on the 87, 89 and 91 pumps "May Contain Up to %10 Ethanol". No sticker on the 94Oct.

 

It isnt that simple. Remember that although the timing may be ok (your argueing octane rating vs detonation right?), the stoichiometric ratio is different.

So although you may not detonate due to too much timing for the octane rating, the car will run uber rich on the gas compared to the ethanol blend.

Dann

 

Yeah I geuss that. So if I tune on 91 to keep it close to the US 92, then up here don't even bother with the 94..

 

uber rich? Actually .2 points that the stock ecu compensates for.. thats nothing.

Tuning on 100% E85 and then running octane.. that will be uber rich.

 

Not talking stock ECU's though. Don't know a stock Miata ECU that you can tune...

I found out today that Shell stations up here don't have any ethanol in their 91 yet. So if given the option for what gas to tune on (and run both once it's tuned) would you choose E10 gas or gas with no E? I'm thinking tune with 91 E10, and it should be fine to run 91 with no E?

 

0.2 points? Its 30%. I ran mine dry a few weeks ago driving laps around a block a sevo was on, just to see what it did with just gasoline and a spanner to drop 15 odd degrees of timing out of it. It was uber rich.

Dann

 

I could be wrong but i'm pretty sure hes talking about tuning O94 vs 91 with 10% blend.

Cheers

 

Alrighty today was the day i went full E85. I added 5% across the map but i decided to scrap it as its clearly lean as rpm/pressure increases. In other words a flat % increase wont do it, cells in boost have to be increased more.

 

Got some more tunning done. I have not done anything with the timing yet still working on the fuel. My car no longer dies when the fans turn on and its the smoothest it has ever ran.... I'll update my standalone over the weekend to V9 and hope for some luck.

 

Still haven't properly tuned for power.

I am very interested in power vs mixture temp. E85 doesn't light off as easily if things are too cold. I think that temp is <50°-55°F. I'm wondering if water injection is detrimental to performance at a certain point. If/when I tune I'm planning on testing with and without WI.

I have to admit that I started to add MMO a few tanks ago. Might not be necessary but it probably doesn't hurt anything. Just hedging my bets. Any good two stroke oil is probably better but I use MMO because it's dirt cheap.

Gas mileage is around 22.5-23 mpg with a/c usage.

 

WI is absolutely unnecessary with E85. If I can find MBT at 17psi and 350whp through the torque peak on E85, water injection is doing absolutely nothing for you.

E85 is magical ****.

 

Yeah I was wondering if you really needed the WI as well.

I want to convert my supercharged E36 M3 to E85 sooooooo bad.

 

So you guys ever figure out a way to tune the timing?