Stage IIe

[merchgod]

This table appears to be only available for the 16bit roms.

there are new warm-up enrichment tables for the 32-bit ECu as well.

[GTkansan]

Im confused about the desire to use e85... the energy density (Kj/Gal) is about 30% less than gasoline. So even if it is 30 percent cheaper than 93, you arent going to get a financial break...

[Infamous1]

Im confused about the desire to use e85... the energy density (Kj/Gal) is about 30% less than gasoline. So even if it is 30 percent cheaper than 93, you arent going to get a financial break...

Obviously you haven't seen the power it is capable of putting out, research!!!

[biz77]

Im confused about the desire to use e85... the energy density (Kj/Gal) is about 30% less than gasoline. So even if it is 30 percent cheaper than 93, you arent going to get a financial break...

 

On a stage 1 tune with ZERO changes to boost, fueling and timing, I picked up another 20 peak whp and 35 peak ft. lbs of torque. I will gladly pay a reasonable amount MORE for E-85 over premium. My only problem is that the one station we have is very much out of the way.

[GTkansan]

I was talking in terms of economy.... A potential price increase for life (net dollars per mile) vs. just swapping turbos or somethign like that. It seems an odd choice to me, but to each his own .

[Infamous1]

I was talking in terms of economy.... A potential price increase for life (net dollars per mile) vs. just swapping turbos or somethign like that. It seems an odd choice to me, but to each his own .

Yeah upgrade the turbo then there is even more to gain....

[mickeyd2005]

E85 is the best price/performance you will get. And E85 is the only mod that will not increase lag.

[Legend]

E85 is the best price/performance you will get. And E85 is the only mod that will not increase lag.

 

Wholly agreed. I gained 0.55s in my best quartermile run in Sept (E85) versus my best quartmile run in May (91oct). That's HUGE. In addition, all 4 of my E85 runs were at least 0.2s faster than my fastest 91oct run. I run nearly a full second quicker quartermile than the other Stage II LGT's at the track and trapped around 6mph higher. (Other factors such as tune involved here also).

 

And I'd argue that the quartermile isn't the best way to show off the power gains. The greatest share of power improvement is below 3500rpms, where you are NEVER driving in the quartermile.

 

I'd also argue that Stage IIe is the BEST setup for around-town stop n' go driving under 60mph. No turbo for our cars spools quicker than the VF40, and with E85 it (or any turbo) even spools a little quicker. Couple that with a huge torque increase that is especially evident around 2500-3500rpm and there probably isn't a quicker LGT from 2000-3500rpm. Since converting, even when driving spirited I find myself shifting at the highest around 4000-4500rpm so that I can catch the next gear in those meaty rpms and a bang of spool.

 

As for the cost of the fuel, I don't care. I'd probably pay MORE for E85 even though fuel economy goes down. I paid $2.59/gal yesterday versus $3.79/gal for premium. I calculated a couple months ago that E85 does save me money, but only around $30 per 1000 miles.

 

I haven't checked out the new cold start tables and just updated my defs yesterday. I'll need to do that soon!

[Infamous1]

there are new warm-up enrichment tables for the 32-bit ECu as well.

I gather it is define quite abit different then?

[merchgod]

I gather it is define quite abit different then?

Quite a bit different than what? The 16-bit ECU? The general logic and tables are very similar. They are under the "Fueling - Warm-up Enrichment" category.

[Infamous1]

Quite a bit different than what? The 16-bit ECU? The general logic and tables are very similar. They are under the "Fueling - Warm-up Enrichment" category.

I will check them out again, thanks.

[biz77]

I was talking in terms of economy.... A potential price increase for life (net dollars per mile) vs. just swapping turbos or somethign like that. It seems an odd choice to me, but to each his own .

 

 

Depends on the price of E-85 where you are at. In my town the spread is actually minimal because the demand is minimal. Last time I checked E-85 was about $3.40 per gallon compared to about $3.80 per gallon for premium here. I average about 16.5mpg running E-85 on my standard loop and about 20mpg with premium. In this scenario I pay 2 cents more per mile to run E-85.

 

The only other upgrade I can think of that will yield similar gains would be the installation of methanol injection. So if we figure a purchase price of $400 for a decent kit and IGNORE the cost to fill it every so often, it would take 20,000 miles to recover our investment. That is two years of driving for me, let alone the potential for failure of the injection system and it's added complexity/installation requirements.

 

So, yes in an absolute dollars and cents standpoint E-85 does not stack up to gasoline for me. For others paying $1 less per gallon it does. When you also consider the fact that our motors LOVE this stuff you will see why some are willing to pay MORE for it. By the way, those of us that use it can switch back to gasoline whenever we want. And a few keystrokes is a much simpler task that installing a new turbo:)

[Legend]

I plotted my 2 best runs in the quarter-mile on 91oct (blue lines) vs. E85 (red lines). Not a lot of new info. here, but adding to my data.

 

http://beeez.com/lgt/e85compared.jpg

[Infamous1]

Have you experiemented with any more boost or timing? I think you might be able to pick up even more acceleration due to E85's resistance to knock.

[Legend]

Have you experiemented with any more boost or timing? I think you might be able to pick up even more acceleration due to E85's resistance to knock.

 

As for timing, I am running around 5-6 degrees more at the big dip around 2600-3200. As the rpms climb I run a constant 3-4 degrees more than I was on 91oct. I have not adjusted timing below 2800rpms nor above 6000rpms. I haven't experimented much, however. I honestly don't know whether I am running a little too much or could gain from more. I set the timing this way based primarily upon what I had read. I know I'm in the ballpark but it's probably not optimized.

 

As for boost, I am running about the same. A few weeks ago I decided to increase my boost just a tad from peaking around 15.7 to now peaking around 16.3 or so. I pushed the taper up as well so that boost at 6000rpms is at 10.5 (previously 10.2). Seems to be about right (pressure ratio) for this altitude. I have boost rapidly falling at 6400rpms since I don't drive past 6k anyways (and doing this keeps me from doing it. )

[Legend]

I just thought of something that might have added to my performance in my E85 runs. I had datalogged my 91oct runs in May. After analyzing the fast-shift boost response I thought there was room for improvement. My boost as I entered gears at 4krpms was running 0.5psi less all the way up than it was versus a single gear 2krpm-6krpm run.

 

I re-scaled my WGDC tables to have increased resolution around the "shift landing" area. I created a WGDC Init peak around 3900rpm, so that as I dropped into gears after a fast shift the boost would mimic the boost on an isolated gear run. I played around with it several times until I got it right.

 

So.. I probably could have done at least 0.1s better this last time even if I had not converted to E85.

[Infamous1]

As for timing, I am running around 5-6 degrees more at the big dip around 2600-3200. As the rpms climb I run a constant 3-4 degrees more than I was on 91oct. I have not adjusted timing below 2800rpms nor above 6000rpms. I haven't experimented much, however. I honestly don't know whether I am running a little too much or could gain from more. I set the timing this way based primarily upon what I had read. I know I'm in the ballpark but it's probably not optimized.

 

As for boost, I am running about the same. A few weeks ago I decided to increase my boost just a tad from peaking around 15.7 to now peaking around 16.3 or so. I pushed the taper up as well so that boost at 6000rpms is at 10.5 (previously 10.2). Seems to be about right (pressure ratio) for this altitude. I have boost rapidly falling at 6400rpms since I don't drive past 6k anyways (and doing this keeps me from doing it. )

 

Excellent! The only thing I really have to compare to E85 is 100oct which is somewhat close in results.

I currrently run about 4 degrees more timing in the sub 3200 rpms region, 6 degrees more in the midrange along with 2 more psi and about 2-3degrees more in the 5500-redline region at the same psi level. All at 12/1 AFR and in comparison to CA91 in all the WOT load regions. It really is a night & day difference, I can't wait to get this stuff!

[Legend]

Wow I didn't know you could run 12:1 on 100oct. I was running 11.1:1 on 91oct and am now running 0.84 lambda (12.3:1) up to around 4500rpm then I let it taper to 0.78 lambda at 6000rpms.

 

By the way, I do plan on posting charts for my timing, AFR, and boost sooner or later. I ought to plot them against my last 91oct tune for reference too.

[Infamous1]

Wow I didn't know you could run 12:1 on 100oct. I was running 11.1:1 on 91oct and am now running 0.84 lambda (12.3:1) up to around 4500rpm then I let it taper to 0.78 lambda at 6000rpms.

 

 

Oh yeah definately, if not I would be stressing the hell out of my bearings or way pass MBT. I run 12:1 along with 21.5-22psi and 18.5 degrees of timing at peak toruqe on my vf39. Not a bit of knock and EGT's are under control as well. Since this my race map I may try to push a bit more boost in the 4K-5k range as well.

[Legend]

Sweet.

 

Did you check out the new cold start tables in the latest romraider defs? Some people with TGV deletes have had good success. It might help with E85 cold start issues.

 

I just got around to checking them out. Looks intimidating. Have you done anything with these yet, mickeyd? Looks like a lot of interplay between the tables. I won't touch these unless I get a problem. My plan is to augment fill-ups with ~2-3 gallons of 91oct and run a modified tune in the winter.

[mickeyd2005]

LOL.

 

What?!?!?! You don't understand it? Yeah, it looks pretty complicated. I was just thinking about Min Primary Base Enrichment.

 

Have you considered a block heater? It doesn't get cold enough around here to worry about block heaters but I can see its advantage in colder climates especially if you are running E75.

 

Do you know when they change the formulation to E75?

[Legend]

Taken from Hotrod's thread on NASIOC:

 

E85 fuel ethanol content seasonal changes

 

E85 fuel blends change content seasonally just like all gasolines blends change with the seasons. This seasonal change in blend for E85 is primarily to improve cold weather starting, where the changes in gasoline during cold weather is to improve cold weather starting. In the summer months, gasoline must be blended to reduce vapor lock and to reduce evaporative emissions.

 

The recommended dates for changing E85 fuel blends are listed in a chart in the E85 handbook on page 22, which is in the "E85 Fuel Specification" tab.

The Volatility class specifications are broken down on page 10.

 

Volatility class 1 --- minimum ethanol 79%

Volatility class 2 --- minimum ethanol 74%

Volatility class 3 --- minimum ethanol 70%

 

 

http://www.e85fuel.com/pdf/ethanol_guidebook.pdf

 

As you can see each region has a different start date and recommendation for seasonal blends depending on local weather climate.

 

Here on the high plains east of the rockies in Colorado we run the class 1 fuel blend from mid June -- mid Sept, run class 2 fuel from mid Sept -- mid Oct and run the class 3 fuel blend from Mid Oct -- mid April, then back to the class 2 blend from mid April to mid June. The standard only specifies a minimum ethanol content, vendors can run higher ethanol content if it is economical. If it is cheaper for the fuel blender to add more he can. Ethanol content is bottom line driven by local weather conditions, and cold starting problems for local drivers just a gasoline blends are modified to give easier starting in cold weather.

 

So it looks like now in mid-Oct I'm probably running class 2, about to go to class 3. Each class is around a 5% drop in alcohol, totally around a 10% difference in ethanol content in summer vs. winter. But because E85 mfgrs have discretion in the blend, the true difference could be more or less... the difference could be as little as 9% and as much as 15%.

 

It's the 15% that has me concerned, as that is the extent of the ecu's authority for LTFT's. I checked LV and my LTFT's have not trended negative yet (my tune was done in the summer with class 1).

 

I will be making some changes to my tune for the change in fuel. I might be able to get away without changing a thing, but feel this is a safer way to go. Here is what I'll be doing:

 

1) I will be increasing my injector scalar. If I don't make any changes I run the risk of AFR Learning D going to -15%, then going lean on WOT. Initially, after I increase the scalar, the ecu will learn to add fuel and my AFR Learning D will go positive. No problem. As the alcohol content decreases it will move in the negative direction. So how much to increase it? Not sure and I'm open to suggestions. There is probably a pretty wide range of acceptable answers here... anywhere between 0%-12% is probably a reasonable answer. My thought is a 6% increase between the E85 scalar and the 91oct scaler. My scalar is 649 for E85 (class 1) and 930 for 91oct. I'll be adding 6% of the difference (6% x 281) and increasing my scalar to 666.

 

2) I will change my AFR's from 0.82-0.85 to 0.78-0.81. I just feel that's safer as the FT's will be fluctuating.

 

No changes in timing. I've added 3-6 degrees but I think I can run this timing just fine.. especially with the richer AFR.

 

I may look into the WGDC by IAT table, the cold start tables, idle timing, idle speed by coolant temp, etc. Not sure if I'll have to take any of these measures and won't address them unless I encounter difficult starts.

 

As always, your feedback appreciated.

[LittleBlueGT]

Not sure if I read that right, but going from E85 to E70 does not constitute a 15% change in AFR.

[Legend]

Not sure if I read that right, but going from E85 to E70 does not constitute a 15% change in AFR.

 

I agree with that, but I'm just uncertain how much of the fuel trim authority will be used going from E85 to E70 (assuming I ever had E85 anyways - could have been E79). I just don't want to see big negative fuel trims, especially targeting 0.84 lambda. I might be just fine not changing the scalar, but setting the scalar at "E79" seems like a decent compromise for all seasons.

[Infamous1]

Wouldn't it be closer to a 5% change in AFR max? I personally would just target a richer lambda, messing with the scaler would call for a modification of the entire MAF scaling.