I want switch to e85, smart people click please

FattyBoomBatty · 09-16-2009

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 · 09-17-2009

i believe that e85 is %25 more fuel

viridionplague · 09-17-2009

(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 · 09-17-2009

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

Quote:

Originally Posted by 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?

CVD · 09-17-2009

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

FattyBoomBatty · 09-17-2009

Quote:

Originally Posted by 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.

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.

Quote:

Originally Posted by 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

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 · 09-17-2009

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 · 09-17-2009

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** · 09-17-2009

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 · 09-17-2009

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?

**4seasons69** · 09-17-2009

I've never heard any problems about the paper filters falling apart. It's all the crap that the e85 loosens up that clogs stuff up

FattyBoomBatty · 09-17-2009

Ok, cool. Thanks. I will be doing this about 5 gallons of gas from now.

jrohner · 09-18-2009

I'm still running the same stock-type filter that was in the car when I bought it in about 2005. No issues. If you're filter gets clogged it's because the ethanol is cleaning all the crud out of your tank and lines.

Andrew7dg · 09-18-2009

When you talk about Fuel map are you talking about your VE table?

I think AEM is MAP...

Anyway if it is a huge map like that, leave that map alone and change another setting. You don't want to change those settings because you are tuning for VE. So those numbers you want correct. Otherwise if you take it to a tuner they will be kind of confused

When I am tuning on my Standalone (which is not an AEM so you will have to search around), there is a box in the general inputs that ask me

Engine Displacement
Number of Cylinders
Injector Flow
Air Fuel Ratio

And that gets me my Required fuel in (ms)

I just change my AirFuelRatio to what I want it which I think is 9.7

And BAM! works

Then I can tell what my actual (close to it anyway) VE is

if this is completely different because of AEM then ignore this

*I am running a WIX fuel filter
what clogged on mine is the screen on the pump. Make sure to change that!

niterydr · 09-18-2009

The -30% is a guideline, every vehicles BSFC is different and thus that generalization will be varied. Idle, cruise, part throttle, and WOT all require different amounts of fuel. The safest bet is to get a wideband and tune it as you go.

I would recommend straight tuning the fuel map to achieve the best results as well as tweaking your modifiers, especially your start fuel as you will need a substantial amount more to start it (cold injector pulse).

Best bet is to watch your fuel in RAW, then take a multiple in reduction.

FattyBoomBatty · 09-19-2009

Welp, it's done, and running fine, I used the map I made where i just dragged the whole thing up 30%, then went into starting fuel and went from 70 to 100. I bumped the boost up two clicks and now it's about 18 psi. Feels pretty good, but very similar to before. I am seeing a tiny bit of noise/knock around 5 grand at full boost, but the voltage is from .0195 (base) to .07 something, so I don't know if it's fake knock or just a tiny bit.

I will try quenching it with fuel a bit first. But then I want to bump the boost up a bit more. I figured I'd be fine with 2-4 more lbs.

**Goat Blower** · 09-19-2009

As long as your fuel system can support it, you'll find yourself turning up the boost a lot. E85 is liquid gold for boosted cars.

FattyBoomBatty · 09-19-2009

I only have 750's so I think I'm limited to about 4 more psi, but I guess the timing could be advanced more. I really need to find out if the "knock" (or noise, I don't know) will go away with more fuel in that area around 5 grand.