OpenFlash Tablet v1.42b maps now available

[wparsons]

Higher octane burns slower (and less efficiently) if the tune doesn't have timing set for it, plus Petro 94 has 10% ethanol while Shell 91 is 0% ethanol.

[FrsDuke]

The ethanol would certainly account for the mpg. I think you've contradicted yourself about slow burn being inefficient. The slow burn allows for higher compression and more advance which increases efficiency. This is assuming it is gasoline and not an ethanol blend. The reason ethanol blends have a higher stated octane yet are less efficient is because of the energy density of ethanol being lower than gasoline. Higher octane pure gasoline is more efficient than lower octane pure gasoline. But pure 91 vs e10 94 is not apples to apples.

[wparsons]

^^ Re-read what I said... if you're running a tune that isn't optimized for higher octane, you lose efficiency because you get less complete combustion.

Now if the tune is set to take advantage of the higher octane then you'll definitely make more power at a higher efficiency, but just throwing higher octane in on a lower octane tune will definitely be less efficient.

[FrsDuke]

I see what you meant. Wouldn't a 91 tune be able to add a little advance over time?

[wparsons]

Depends how much advance was tuned in. If it was already maxing out the advance (ie no knock at all) on 91 octane, putting in 94 octane wouldn't net any gains without adjusting the tune. If it was getting some knock on 91 and not running the full desired advance then 94 would net some gains.

[FrsDuke]

Fair point it's unlikely that an off the shelf tune would go knock hunting. Far more likely it would max at a relatively conservative level. Thanks for having a civil conversation on the Internet with me! Refreshing stuff.

[Terrapin77]

With it being in the 20's in Atlanta in the morning the past few days, it has been a PITA starting my car. Using the photo below, I edited the cranking parameters in RR. I'm happy to say I had no difficulty starting the car this morning.

Originally Posted by Malt

This will largely be fixed once more than two maps can be loaded onto the OFT at the same time. I have the E85 map I'm using plus a normal Stage 2 map loaded just incase I have to take a trip somewhere and there is no E85 available. I knew I wasn't going anywhere yesterday or this morning other than work and then home so I guess I could of put my previously known working E85 map on there instead of the normal stage 2. With the ability to load 5 maps I could of loaded the new beta map and tested it when it was cold without fear of being stranded. Regardless I got it cranked finally after 45 minutes of trying.

Here's a data log of a couple attempts to get cranked for those that are curious. Not sure how helpful they will be. http://www.datazap.me/u/malt/cold-st...-12-16-13?1-11

Disclosure, I make no claims as my abilities of tuning a car or even adjusting tables in these maps. These changes were the result of discussions with much more knowledgeable people than me. They were not my idea so don't give me credit.

For those of you that are potentially having cold start issues like me, here is a copy of the tables I've used with success. It starts on the first try 80% of the time and on the 2nd attempt 99% of the time. These changes have worked for me for temps down to 21 degrees. Below that I have no clue and make no claims to its ability to work.



Essentially its the tables used on the 1.40 E85 maps but with the 68 degree columns multiplied by 1.2, the 50 degree columns multiplied by 1.25 and everything below that multiplied by 1.3

The Fuel IPW Compensation A tables are zero'd out.

[Shiv@Openflash]

Good work Malt! If i get some more positive feedback from those changes (from people still having cold start issues), I'll incorporate your updates to the OTS mapping

[enwave]

I had my first cold start issues today, without the revisions. Stumbling after an initially successful seeming start. Wasn't a big deal though, second attempt worked great.


Sent from my iPhone using Tapatalk

[nlowell]

I'm in San Diego and it's been 65 degrees at 8am when I try to start my car and I've had multiple failed starts every morning. Today I had 6 failed starts with a couple of spits and sputters each before it finally started on the 7th turn. My neighbors must think I drive a clunker...

It wasn't this bad from my first few tanks of e85 but then I switched to a brand new station that opened up closer to my house. I'm thinking the newer one has higher levels of ethanol and that is causing the rough start but I haven't tested it yet. I would love a fix because I can feel the power and don't want to give that up

[garfull]

i had identical experience. even at 65F in my garage the car would burp and fart horribly before finally starting. finally gave up and went back to 91oct. when the cold starts gets addressed i'll go back to e85. i miss the power already.

Originally Posted by nlowell

I'm in San Diego and it's been 65 degrees at 8am when I try to start my car and I've had multiple failed starts every morning. Today I had 6 failed starts with a couple of spits and sputters each before it finally started on the 7th turn. My neighbors must think I drive a clunker...

It wasn't this bad from my first few tanks of e85 but then I switched to a brand new station that opened up closer to my house. I'm thinking the newer one has higher levels of ethanol and that is causing the rough start but I haven't tested it yet. I would love a fix because I can feel the power and don't want to give that up

[Terrapin77]

It was 7 degrees in Atlanta this morning. It took 25 cranks to finally get my car started. Once it did start, a massive amount of blue smoke came out of the exhaust. Hopefully that was due to the number of times I had to crank it before it started. After the engine was running for 10 seconds, the blue smoke went away. I think I will be going back to 93 octane until this Arctic blast covering the country dissipates.

[Terrapin77]

So instead of admitting defeat & going back to 93, I increased the cranking tables in my map by 10 to 20 percent. I did this to the all coolant levels 32 & below. It's 20 degrees in Atlanta right now and the car started on the 1st try. It did gurgle a little bit but at least it started right up. Here is a screenshot of my cranking tables

[Indestruct]

I'm on my second tank of e85 and i'm starting to get the failed starts. I had to press the starter 3 times one time, kind of embarrassing cuz i had a female in the car lol.... The sputter/slow start is normal now. I'm hoping SHIV will incorporate the changes other users are doing for cold starts or else this will be my last tank of e85...