Mijae007

Im curious to see what folks here on e85 with turbo setups are tuned to. This might be difficult to answer since most of you are probably running a flex fuel setup with varying levels of ethanol. Anyway, before getting real technical, just wanted to gather an average target afr -if you will- of current owners.

What type and size of injectors?
What rpm is your idle?
What is your target afr for idle?
What is your target afr for part throttle?
What is your target afr for wot?

I only ask because i couldnt find any info on this and everything that does exist is based on pump gas with average target of 11.8afr for wot. My understanding is you can run a lot leaner on e85 (as much as 12.5afr according to my tuner) on boosted applications where normally on pump people would garget 11.8afr.

MorngWoodStewie

E85 does run cooler, and the engine will naturally want to lean out at the top end wot anyways, so for the sake of making more power and E85 allowing this, it is leaned out.
this just goes to show, more doesn't equal powa.

Pump is enriched to keep the charge cooler, to resist pre-ignition. This shows that the compromise for safety and longevity outweigh the minimal loss in peak power.

Even on pump tho. I saw my AFR plot lean to 12 during the last couple hundred Fred rpms. It's really not that drastic, but is deftly different between the two. Tuning
AFRs only make up about 5% of the power u can add to a setup. The rest is parts/setup/heat soak/weather variables/timing (which will yield the most) stuff like that. Staying on topic, and just fyi I'm not E85 but for idle I would suggest what ever stoichiometric is for E85 for idle, and then tune from there. A tuner should know how the car is gonna be used and TGT to accomplish those goals.

Enrichening in the mid range will usually yield some trq but as the engine starts transitioning to the top end it will want to start leaning for max peak yields. Now how much that is also has to be balanced due to how it's gonna be driven to make it "safe"

I don't know alot about E85 but last I read it is oxygenated I believe so, finding someone that is familiar with E85 will be ur best bet.

The common pump TGT thrown around is usually around 11.8 not 10.8.

Mijae007

Ah thanks, just edited that in the original post. Still wondering what people are running. My tuner said we can target 12.5afr at wot on e85.
on another note how much does weather factor in to changing afrs. Its currently 60deg here in socal. If i tune to 12.5 now, will i need a retune in the summer when its closer to 100deg or should i be fine?

MorngWoodStewie

If your on a standalone, I would bring that up with your tuner. I'm on Flashpro and I would assume the stft and ltft would be able to dial in the differences with ever changing weather conditions, as long as the parameters are set to be able to cope with them.
Good question! I'm curious to hear from some of the more knowledgeable engine management peeps on here about that in particular.

I just got orders for ft Riley KS. So wx conditions will be a lil more varied then say the tropical 60*-100* throughout the yr.

Spoolin

Same AFR typically applies with e85 as it does with gas. That's the way my tuner sets mine up. 13.5 idle due to 2200cc injectors not liking to run much leaner smoothly on e85, 14.7 cruising and around 11.8 WOT. Your power will come moreso from timing rather than AFR if you keep within gas parameters.

MorngWoodStewie

Ya, I didn't think there was much of a difference. Of course if something doesn't look right, have it checked up. But for the most part if your confident in the tuner. Don't stress; have fun

yamahaSHO

E85 can be run safely, with good power between 11.4-12:1 on a gas scaled WB gauge. I generally run my (and customers) at 11.6ish so that there is some wiggle room in both directions. EGT's will go up as you lean it out. You can lean it out to a point where you feel a significant power loss, but you won't knock, but you will raise EGT's.

Easy thing to dial in with a dyno as the fear of knocking is pretty much non-existent.