**UPDATE**

I didn't realize that the unit actually had some adjustment before making this post, so further updates are to come once I get another tank of e85 and richen the mix back up

***********


So this has been a pretty hot topic from time to time, with recently another member obtaining a kit from change2e85.com and reporting excellent results. Testimonials on the website show another s2000 owner who reported pretty decent hp/torque gains with just the conversion and no tuning.

With rising gas prices and E85 staying "low' comparatively, and people reporting comparable gas mileage, I decided to take the plunge. The one e85 station around here is right next to my work, so it would be really easy to just fill up near work every week.

DO NOT run this kit. It simply cannot keep up with the demands of the F20/F22. It may work for less powerful motors or for people who only commute, but I don't see how other s2000 owners are reporting success with this unit.

The unit does indeed do SOMETHING at least. It does increase the injector pulse it seems. After I had 100% e85 in the car and unplugged the unit the car had trouble starting up and idling. Plugging the unit back in returned it to a stockish idle, so at least the kit keeps up for idle.

The kit also works acceptably when cruising. I was able to make the drive to Greensboro and back to Raleigh to see my sister without issue. The car actually ran amazingly smooth and the engine was super quiet. I was actually really impressed at this point.

HOWEVER, it's hard to ignore a 30% decrease in MPG. I don't know how people can claim "I haven't noticed any difference". When I had only gone 90 miles on a half a tank cruising on the highway I knew this wasn't going to fly economically.

THE WORST PART comes when you try to go above 50% throttle.

Using my handy dandy obd2 datalogger I was monitoring short term and long term fuel trims like a hawk. STFT was constantly around 20-30%. What's interesting is at idle and cruise on the highway the LTFT was actually able to remain on 0, which meant that the e85 conversion kit was pretty much working. The problem is the car would then go extremely lean if you tried to give it over 50% throttle, and forget about full throttle!

I spent an entire tank of e85 driving around town aggressively. I was able to get the LTFT up to 20% in addition to the corrections being made by the STFT. Only then did the car start to run almost acceptably at increase throttle angles. I could still tell that the car was much weaker than when running on 93 octane however. The next problem was that 1 12 mile trip down the interstate to work was enough for the ECU to lower the LTFT back down to 0, which now meant that I can't go full throttle again, and would need to spend a whole tank of e85 again getting the ECU to relearn.

It was because of this fuel trim problem that the kit has come out and is being returned for a refund. It does not work with an s2000 correctly. I don't understand how you can not notice a huge performance decrease and GIANT decrease in fuel economy.

My belief is that these kits are a scam. They half work, and maybe if you don't have the tools to monitor what your car is doing and don't drive a performance vehicle you might not notice that the car isn't running at peak performance. Those of us who DO notice it doesn't work right have the option of returning the kit for a refund, but are charged a $10 restocking fee or something.

No matter if the customer is 'satisfied' by the product or if they hated it and returned it, the seller still makes at least $10

Hopefully I can spare this from happening to anyone again

The car still runs great though, so there don't appear to have been any damages, I'm just glad to be back on gas.

 

yet another scam. thankyou for sharing deathsled

 

Great writeup....thanks for the info!!!

 

did you adjust the potentiometer inside the box? if you had the unit set on the leanest setting that would explain why you were experiencing problems. I just returned from a long trip and i was averaging around 23 mpg on the e85 and 25 when i was running 93 octane. I even unhooked the unit for two tankfulls of 93 octane and the mileage was still 25 mph. Again the conversion works awesome on my car, not sure why you had trouble with yours.

 

oh so there IS an adjustment inside the box? Well damn now that has me wondering. The instructions that came with it were pretty shitty, and I was afraid if I opened the box it wouldn't be returnable.

That actually makes me feel kinda silly now.....

I guess I still have 3 weeks of testing I can do? It's a shame cuz I've got a full tank of 93, lol. It was 4.19 a gallon!!!! E85 is still 3.29 here, so now the savings are almost a dollar!

That would explain why with the box the car runs so well on 93 still, I thought it would be rich as hell.....

That raises another question though, if I was that lean, why was I getting such terrible gas mileage? lol

Oh well, maybe I'll give it another shot, time to go look inside the box....

**edit**

do you mean INSIDE the box? I just noticed that there are some dip switches on one side of it that I had failed to notice before.

This looks bad on my part - chalk one up for poor observation skills!

See, I WANT this technology to work, lol

Did you have to change your settings? What are you set on now? Sharing that info would be helpful. The manual for the full flex gold doesn't even detail what they do very well. Right now both the switches are up to "on". It looks like I can switch the first one to off, and that is the one setting that I have that richens it up?

So basically there is no fine tune adjustment I get to flip one switch and that may or may not solve my problem, lol

 

my kit is one of the older ones with the switches inside. Sounds like you have the newer kit with the switches on the side. there should be a diagram that shows the rich to lean adjustments that are available. there are 4 settings on mine. i currently have mine on one setting above lean. I have also tried it on one setting below rich. seems to run good on both, however uses more fuel on the setting just below rich. when mine first came it was on the richest setting and it ran kinda rough and used alot of fuel, also didn't want to rev. once i figured that out and made the adjustments it has ran like a champ ever since. call Dave at change to e85 and see what setting he recommends for your particular conversion. I wish i had the same kit so i could walk you through it. Let me know if you have any questions, i would be glad to help.

 

Well I think there's no difference aside from the fact that my switches are apparently outside the box and that I am blind, lol

so there are 4 settings total from leaner to richer:

off off, on off, on on, and off on.

Mine was "on on" already, so the only place I have to go is to "off on", because I'm pretty sure I'm lean.

I'm gonna go record some more logs on pump gas just so I have something to compare to. I admit I didn't hook up my logger until after I was on 100% e85.

 

WTF?! You need an OBDII monitor and you get a single trim point? Welcome to 1985.

 

well you don't need one I just happen to have one.

And yes, you get a single trim point It's crude but effective.

This is actually the cheapest way to accomplish the basic correction needed for e85. You could do the same thing with an AFC and have more adjustment true, but an SAFC or VAFC will be modifying the MAP signal and tricking the ECU. This unit intercepts the injector signal after the ECU and alters it without changing another engine parameter.

The only other way to accomplish that would be to have a unit like the AEM FIC or Emanage Ultimate but now you're getting more expensive and you probably need to have it professionally tuned, unless you just wanted to throw an overall injector size correction in there, but now you're spent like double the money to accomplish the same thing this unit does.

*****

I also think part of my problem may be that I run an AP1 ecu in my AP2. I didnt check the fuel trims before, but I bet the ECU already had a positive correction in the LTFT due to the increase in displacement. This may explain why I've only got 1 setting left to richen up the unit vs Wirelessguy who I think has at least one more setting he can use to go richer.

Hopefully the unit on its richest setting gets me to the same level he is currently at. If not, I may try the AP2 ecu for giggles, but I don't want that lower redline

 

did you get a chance to talk to dave at change2e85?