Now that winter is pretty much over and I've had a chance to drive around in warmer conditions again, I can comment on how E85 performs in winter. First of all, I pretty much stayed off boost for most of winter because I thought that I had a clogged fuel filter that was lowering fuel rail pressure.

However, I did plenty of daily driving during the winter. With the right "cranking enrichment" and ignition timing values, the car starts fine in the coldest temps that I experienced (20 deg F). As far as actually driving the car, what I didn't realized until the temps warmed up is how much less responsive E85 makes the engine in cold weather. I could tell during the winter that the car was ******* a bit, and I figured it was due to E85 not atomizing well in cold weather, but it wasn't until the air temps warmed up that I realized how much it was *******. In warmer weather, the car could accelerate reasonably well while keeping the car off boost, and I could lug the motor around at 1800-2000 rpm no problem. However, in cold weather, I had to get a bit into boost (maybe 3 psi) to get reasonable acceleration and the motor wasn't happy being lugged around below 2000 rpm.

The same sort of thing happens with gasoline, but not nearly as much. I'd say gasoline would be more responsive during daily driving down to about 35 F, and then after that, it would start getting less responsive. It feels like E85 starts getting less responsive below about 50F.

 

My Eclipse on E85 always starts and idles just fine without ever touching the throttle, even when it's below zero. I hope that doesn't change with the Evo 8 ECU I just installed. When I put it in, all I did was disable the immobilizer and it started right up, and it was still pretty chilly outside. After a couple minutes of running it wanted to die though and I noticed it being lean, especially lean for still not being warmed up at all. It turns out that the injector size was set at like 780 or something. I set the injector size(I need it @ less than 500 for my 750's on E85), and changed the MAS scaling to a 2g DSM, and it now idles better than it ever did on the 95 DSM ecu. I'm very much looking forward to retuning it after I fix my broken Fidanza 4.3 6-puck. Hopefully I can beat my 414hp/459 torque with the much better logging capabilities and the ebay tubular o2 housing I'm going to install.

 

I've started a small retuning session after having an O2 housing installed and having the exhaust manifold and hotside ported. I've been slowly pushing up the boost about 1 psi and leaning out to around 12.2:1. There is one occasion in my two most recent logs where the ECU registers a few knock counts and the AFR goes momentarily lean. Since E85 knocks less at leaner AFRs, I'm wondering if this is a classic sign of spark blowout or misfire.

 

Misfire should show up in your logs as a brief spike in the O2 signal or wideband. If it's prolonged enough, it will feel like a mini fuel cut.

 

Its not so much of a spike as it is a hump over about a 400 rpm range.

 

After fixing several boost leaks and installing a cone filter, I picked up 1 mpg. I'm now up to 17.3 mpg during daily driving that includes a bit of spool time. If highway mileage has gone up 1 mpg too, I might actually be able to make it to Portland (230 miles) on one tank of gas.

 

what would be a good starting point to tune with rc750cc? i'm doing all the reading i can right now and i was told before i start i should obviously drain the tank and lower the latency values for the injectors? what's a good starting value?

 

Start with draining the tank, put in E85 and change your injector 'scaling' not latencies unless your fuel trims go way off. Search through https://www.evolutionm.net/forums/ec...injectors.html for the right scaling/latencies on E85 for your brand and type of injectors. Before you start tuning the car, run the first tank of E85 down just to make sure no pump gas is left. Start with 24psi first, lean it out to 12:1 AFR and check your IDC%. If you still have some more room, bump up the boost and fix your AFR again. Once you find that you're close to 100% IDC then stop and adjust timing etc..And please read this thread https://www.evolutionm.net/forums/ec...on-timing.html before you start making some crazy @$$ timing maps because how E85 is capable of running timing.. Good luck! You'll love E85!

 

sounds good. thanks for the info

 

good info

 

And how would you go about doing that? Running all the pump fuel out? I'm guessing let the car idle until it just dies? Is it safe for the motor?

 

MRFRED, I'm assuming that you only adjusted the 4 coolest settings: -25, 0, 18, & 44F. Is this correct? Do you recall the original settings? I'm just curious about how much you increased the enrichment.

Thanks,
Jim

 

Yes, I would probably change values in that temperature range. However, that table is now a bit outdated, please read this thread:

https://www.evolutionm.net/forums/ec...l-options.html

The catch is that if you are running a 9417XXXX ROM, the new tables have not yet been defined for your ROM.

 

Anyway to have those tables for v7 alt maps? I just don't know the correct address for the tables.

 

Saw your other post on this. I can help you with this later today. PM me to remind me.