I want switch to e85, smart people click please

[FattyBoomBatty]

Ok, I've got an AEM, and when I go to the fuel map, I can highlight the whole thing and increase it by 30%.


If I go to a gas station, fill it up with e85 and do that, will it run well enough to drive around for a bit till I get enough gumption (monies) to get it re tuned? My injectors were at 53% duty cycle, last time I checked, so they should be fine with 30-31% more DC.

Or are there any tricks to switching that I should know? Should I turn off O2 feedback at first, or leave it on, and I've heard 30 percent more and 31% more fuel, I know it's close, but I have the option to do either one, so which is better?

[jhaan_dude]

i believe that e85 is %25 more fuel

[viridionplague]

(stock injectors/(Injector Flow * .65))-1.0 = E85 Global

you can substitute .70 if you wanna run on the leaner side.

when i switched all i did was run the tank down, fill up with e85, changed my global according to the calculation, and drove off.

[blackrosenova400]

It would be 30% more of what you were using, not 30% more duty cycle. So add 30% more of 53%.

Around 68-69%

Do you have a wideband? You should get one, great investment :)

Ok, I've got an AEM, and when I go to the fuel map, I can highlight the whole thing and increase it by 30%.


If I go to a gas station, fill it up with e85 and do that, will it run well enough to drive around for a bit till I get enough gumption (monies) to get it re tuned? My injectors were at 53% duty cycle, last time I checked, so they should be fine with 30-31% more DC.

Or are there any tricks to switching that I should know? Should I turn off O2 feedback at first, or leave it on, and I've heard 30 percent more and 31% more fuel, I know it's close, but I have the option to do either one, so which is better?

[CVD]

*edit - gonna make my own thread so I don't completely hijack this one.

[FattyBoomBatty]

(stock injectors/(Injector Flow * .65))-1.0 = E85 Global

you can substitute .70 if you wanna run on the leaner side.

when i switched all i did was run the tank down, fill up with e85, changed my global according to the calculation, and drove off.

What do you mean by stock injectors? I have 750's, and stock was two injectors that totaled around 440cc. It will never be stock again, so does that have an impact on the calculation? When I used 750 for both variables, I got .53 so I'm good and lost on that one.

It would be 30% more of what you were using, not 30% more duty cycle. So add 30% more of 53%.

Around 68-69%

Do you have a wideband? You should get one, great investment :)

I do have a wideband. You are the first person to bring that idea to my attention, thanks. I just want to be sure since I've blown up more than enough engines in this car, and I really don't want to add the current and most expensive one to the list.

So, with what you are saying, I should have more room to go than I thought and I'd be well within the safe operating limits of the injectors. This could be awesome.

[jrohner]

I scale my injectors by taking the real injector size and divide it by 1.4 and then round the number down to the nearest possible number on the scaling. My 750's were scaled at 526 I believe.

Your injectors being enough depends a lot on what AFR you're tuned for currently and what you'll tune for on E85.

I'm running 750's with 414 awhp / 459 torque (dynojet) and they have always been great. Now that I've gotten my car to hold a few more PSI on top end, I put in the PTE-1000's that I've had for a while and haven't been using.

[FattyBoomBatty]

With the AEM I don't think you scale the injectors like you're talking about. You just set the size in an option box and then work with the map and modifiers. I had to check on how to perform a function to the fuel map, and it's really easy, all I do is highlight the map and enter the function (x*1.30) and it magically raises the entire map 30% (of the existing values). So, now I also heard that paper fuel filters disintegrate and clog up other filters. I have one wix type clear inline filter before the pump, need to check if it's paper or not.

[Tachyon]

It really depends on how much gas (non e85) you have left in your tank.

When I switched over a few years back, I set my global fuel up an additional 30% and it ran like crap because I still had 4 gallons of 91 in the tank. After a few minutes of leaning the fuel map out, it ran awesome. Next time I filled the tank I had to do a little more adjusting (richen it up a tad) since it was then nearly 100% E-Whatever-is-sold-in-MN. I know on my car, I also had to add a good deal more timing in to get power back to where it was.

GL with your switchover.

[FattyBoomBatty]

I will let my tank run down until the light is constantly on, then attempt the switch. I'll just put 5 gallons of e85 in there, that should be enough to overcome the 1/2 gallon or whatever is left in there at that time.

And as far as the paper filter thing goes, yes, I do have a paper filter, but is it the paper falling apart that causes the problem or junk in the tank that the e85 loosens up and clogs up the filters with?