There will probably be several new threads (one for the injector swap and retune, one for the change in fuel curve vs. torque, one for e85 retune suggestions / results, then possibly one for the motor rebuild).

 

I have been running E85 for over a week, and have driven probably 500 miles (more than normal). As I knew I would, I have totally geeked out on the retune.

I have a lot of info to share about the injector swap and tuning, but I'm going to wait for most of that until I take my car to Jotech for a dyno test.

Until then, I figured I'd share that my car seems to run better on E85, especially at idle, and it seems impossible to make it knock. It didn't seem to matter how much ignition timing I ran, it just wouldn't register any knock counts, and it ran very strong.

My fuel economy went down, as expected. I typically get about 21 MPG with regular commuting, but that went down to about 15 MPG with lots of WOT tuning time. On extended highway driving at about 70 MPH, I got about 22 MPG. So it seems that I get about 50% better MPG with E10, but since E10 costs more, I seem to be getting about the same miles per dollar.

It is also clear that it makes more power. I've never had a single modification that made as much of a difference. Using my FlashPro datalogs to generate HP and TQ curves, I believe E85 is giving about 13 ft-lbs of peak gain and about 25 rwhp peak gain. However, I should add that some of the gains seem to be due to the larger injectors alone, since I did notice some gains in the higher RPMs just from swapping them in BEFORE switching to E85.

BTW, the light dashed lines represent my fuel curve, but is unitless. I just like to compare the fuel curve to my torque curve as a measure of how good the tune is.

 

How much of the fuel system did you have to modify?

 

^ good info.

Jotech as in Kenny Jotech?
Tell me that you're just there for the dyno.

other than that, carry on

 

The only modification I've made so far was to swap out the OEM injectors for larger ones (630cc Siemens Deka). However, if I decide to run E85 all the time, I'll research what else needs to be upgraded.

I've never been to Jotech, but I assume they have a nice dyno with lots of previous S2000 data files for comparison.

 

They have lot's of lanes Dyno's probably. Not sure how much a Turbo'd S2000 dyno would help you.

I thought E85 would damage fuel lines and any hose or tube would have to be switched to silicone or a hardline.

 

I figured they would have at least as many S2000 dyno files as anyone in Dallas.

I won't pretend to know how much of a problem I would have with the fuel lines. However, the fuel system was totally redesigned for the '06 models, and E10 was everywhere by then. I would have to believe that Honda would have made some effort to make the system somewhat tolerant of Ethanol.

 

I don't think so, Honda never said the cars were E85 compatible.

 

Don't go to Jotech. T1 (Tony) knows so much more about S2K tuning than Kenny... Ask me how I know. LOL. Tony also has tuned several E85 swaps and even has a conversion kit for it. Give him a call. He is very good to work with.

If you have followed any of my threads in the FI section, Jotech tuned my KPro turbo'd car first, and didn't really seem to know KPro. Tony fixed my car and re-tuned it. Night and day difference in the tunes.

PM if want more info, but from experience, Tony is the better tuner.

 

I was doing some more reading, greg, and both tony and jeff from evans tuning have said that nothing in the fuel lines need to be swapped to make it "safe" to run e85 in an S. Hopefully that means for awhile, not just for dragging purposes.

When you switch fuels, how are you going to resolve the issue of having a little e85 left in the tank/lines, and using that up before going back to e10?

I'm hoping that maybe you can just start it and drive on it carefully for a short while then switch to the map for the other fuel?