E-75 vs E-60: quite a difference...

[Dave D.]

Car was previously tuned on E-60, and made a respectable 372whp/372wtq on Infront's mainline dyno.

Took it back down the other day, to smooth out some idle issues and to replace a Cobb flex-fuel sensor under warranty. This time I had 76% ethanol in the tank. A test run on the Mainline with the existing E-60 tune netted quite an increase: 400whp and 404wtq -- which on this dyno is about double what a stock STI makes.

It was running a touch lean on the E-75 so John made an adjustment, with the final numbers 394whp/414wtq. That's +22hp and a whopping +42tq over the E-60. This was with no loss of spool, in fact, it spools even earlier. On the Dyno it started to drop a bit after 7000rpm, but John told me this was due to climbing IAT's up top. On the street with shorter pulls the drop-off should be negligible if the IAT's stay under 100F. I was able to confirm this on the drive home.

Car: 2006 WRX
Tuner: John at Infront Automotive, Redmond, WA
Dyno Info: Mainline
Transmission: JDM 6-speed
Gear:4th
Fuel: E-75
Peak HP: 394
Peak TQ: 414

Baseline hp/tq for an Sti on same dyno: 200/200
Target Boost: 25psi tapering to 21

Engine/Power Modifications:

IAG Stage 2 block
Blouch Dom 1.5-xtr/10cm
Test pipe w/internal gate
ETS intercooler
Invidia Q300 catback, Gimmick inlet hose
1300cc injectors
Cobb intake
Other mods include AOS, Killer B ELH header, 450lph E-85 surge tank,
TGV deletes, Grimmspeed Uppipe, Killer Bee oil pickup and windage tray. New cylinder heads with a built valvetrain including Kelford 199-b cams.

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[K3rm1tth3fr0g]

interesting. Where do you buy your fuel?

[Dave D.]

Originally Posted by K3rm1tth3fr0g

interesting. Where do you buy your fuel?

Shell station, Smokey Point exit. About 1 mile West of I-5.

[K3rm1tth3fr0g]

Originally Posted by Dave D.

Shell station, Smokey Point exit. About 1 mile West of I-5.

Ill definitely have to look into that.

that spool on ethanol is insane, larger fuel mass means faster spool but damn that's some fast spool for a 1.5xtr.

I bet you're glad to finally hit 400whp on the mainline dyno

You're only like ~150hp off from the highest their dyno has ever read. Jan told me a 550 whp Evo set the record out their dyno. You're not too far off lol

Good ****

[neko]

Curious.. why dyno in 4th gear? Wouldn't 5th be closer to 1-to-1?

[Dave D.]

Originally Posted by neko

Curious.. why dyno in 4th gear? Wouldn't 5th be closer to 1-to-1?

From what I understand wheel speed on the dyno has a lot to do with it. In fourth gear, the drivetrain is going over 100mph by the end of the run. If it were done in 5th, the drivetrain would be spinning over 130mph.

That's 70% more kinetic energy if something goes wrong, a tire blows out, car jumps off the dyno, etc.

When I had the original 5-speed, dyno runs were done in third, as the 5MT would just touch 100mph in that gear.

[Scuby04STi]

Originally Posted by Dave D.

From what I understand wheel speed on the dyno has a lot to do with it. In fourth gear, the drivetrain is going over 100mph by the end of the run. If it were done in 5th, the drivetrain would be spinning over 130mph.

That's 70% more kinetic energy if something goes wrong, a tire blows out, car jumps off the dyno, etc.

When I had the original 5-speed, dyno runs were done in third, as the 5MT would just touch 100mph in that gear.

Had a car up to 205mph on a dyno once, there is GOOD reason to keep wheel speed to a minimum. LOL

[SkylaneRG]

Hi Dave, your post got me curious.
My 2012 WRX is also FF tuned. During the dyno session, the highest concentration seen was E51. I assumed that any ethanol concentration above that wouldn't materially alter my map. Your post suggests otherwise?

Also, on a related note, I stop by that same station for E85. After multiple tanks, the highest concentration I could hit was around E70/71, that was with fuel purchased around March 2020. Wonder if that was their winter blend, or if they ever get closer to 85?

[Dave D.]

Originally Posted by SkylaneRG

Hi Dave, your post got me curious.
My 2012 WRX is also FF tuned. During the dyno session, the highest concentration seen was E51. I assumed that any ethanol concentration above that wouldn't materially alter my map. Your post suggests otherwise?

Also, on a related note, I stop by that same station for E85. After multiple tanks, the highest concentration I could hit was around E70/71, that was with fuel purchased around March 2020. Wonder if that was their winter blend, or if they ever get closer to 85?

My tuner said that there are benefits to be had all the way to about E-70. My personal experience seems to say he's right.

The Shell station I go to seems to top out at about E-76 in the winter. The way I get it down is either to stay on "E-85," or, let it get down as far as I can before I make the trip to fill. What really works is to not just fill up the tank, but to bring about 6 5-gallon cans as well. This way I can keep a can in the car and let it get way, way down. After a couple of cans' worth, the dilution is at least E-70. And I can drive to the station much less often.

But it's tough to get the concentration up if you are just filling your car's tank that probably has at least a couple of gallons or gas left over.

[SkylaneRG]

Do you know if the Cobb FF computer can dynamically adjust beyond what what was seen during the tuning run? I’m familiar with how the Cobb computer works in these edge cases.

As far as driving your tank concentration up, I did the same. Brought multiple jugs, and filled up. Yo-yo’d the tank below E a few times. Found that the best I could achieve was around E70 in March at the Smokey point Shell. I’m wondering if the E85 was absorbing meaningful moisture sitting in my garage.

Good to know that law of diminishing returns kicks in around E70. Took me a few adjustments to get my cold start map ironed out. Imagine E85 and higher can become a pain in really cold areas.

[Bariga]

You sure it wasn't just higher timing based on E content ?

[Dave D.]

Originally Posted by SkylaneRG

Do you know if the Cobb FF computer can dynamically adjust beyond what what was seen during the tuning run? I’m familiar with how the Cobb computer works in these edge cases.

Originally Posted by Bariga

You sure it wasn't just higher timing based on E content ?

Seems like that's what it was...except for an idle adjustment, the car's tune was not changed on the first dyno run that generated over 30whp/wtq difference. John said it was running a little lean, richened it a bit, and that's when it made another noticeable gain in wtq.


There was a temp difference (about 12 degrees) this time, but both time temps were fairly moderate -- 59F vs. 71F.

[BSPS]

hoping to try bit ethanol in the near future

[scoobyfast]

Careful, it's addictive.

[Dave D.]

Originally Posted by SkylaneRG

Also, on a related note, I stop by that same station for E85. After multiple tanks, the highest concentration I could hit was around E70/71, that was with fuel purchased around March 2020. Wonder if that was their winter blend, or if they ever get closer to 85?

I think you are correct about the winter blend. I traveled there yesterday to refill my car and some tanks, and, with about 3 gallons of E-76 in the tank, the percentage dropped to E-73 or so. I know on the pump it says "guaranteed to be at least 70% ethanol," so I'm guessing it's pretty close to that for the winter now.

[MilleKentky]

Hello. I drive a regular Kia Soul every day. On a day off, I have a WRX that I bought recently. At that moment, the forged piston rod group had already been installed, but the owner had not yet had time to inflate the car. Now I’m looking for really normal specialists who can make me 400 or more horsepower, without the use of methanol. By the way, this is what my baby looks like.

[Dave D.]

Originally Posted by MilleKentky

Hello. I drive a regular Kia Soul every day. On a day off, I have a WRX that I bought recently. At that moment, the forged piston rod group had already been installed, but the owner had not yet had time to inflate the car. Now I’m looking for really normal specialists who can make me 400 or more horsepower...

Nice looking car! Fill in your profile so that members near your area can recommend a tuner location.

[MilleKentky]

Originally Posted by Dave D.

Nice looking car! Fill in your profile so that members near your area can recommend a tuner location.

Yes, I will definitely do it, thank you

[K3rm1tth3fr0g]

Just realized your post says InFront is in Redmond not Auburn. I literally made the EXACT same mistake when I first asked someone for a ride home after dropping my car off there for the first time... And they were not happy when I made the correction that it was Auburn not Redmond LOL

[Dave D.]

A bit of a late info addition. I've been asked what my IDCs are, and I finally got around to setting my Accessport to check. With max boost of 25.5 psi (tapering down to maybe 21), on the street, I got the following consistent figures (rounded). Shifting at around 7200rpm, IDC is just under 85%. If I bounce it off the rev limiter, 8000 rpm, done both in 2nd and 3rd, IDCs were just under 95%. This is on E-80. I don't make a habit of or have a need to shift at 8k, so it looks like everything is good.

[K3rm1tth3fr0g]

I'm sure with your fueling setup if you bumped up base pressure even just a little bit you could run pure E85 or even E98 without a problem. And maybe your ETS TMIC is maxed out, but I bet if fuel pressure and boost were increased a bit, even on your current TMIC, it would make more power.

95% is a bit higher than most what I see most tuner's considering safe. But to be fair, this 95% is when you are bouncing off limiter, not just when going WOT. The highest you've been actually tuned for is E75 right? Your tune just is scaling IPW based on the current tune in this post, correct? Like I don't think the tune increases boost or anything aside from just adding more fuel when it sees higher E content than what you were tuned for.

I'd bet there's a decent bit left in your setup given you were to be retuned on some higher concentration ethanol, with fueling to match.

I wonder if banging off fuel cut in 4th or 5th would max out the injectors from the greater load.

John and I decided to use pump ethanol for most of the flex fuel tuning we will be doing, since it is what I will actually be seeing on the street, and then to blend in some VP X85 at the end of the calibration to get some clean, high ethanol content pulls to dial in boost/timing at that higher concentration levels.

[Dave D.]

Originally Posted by K3rm1tth3fr0g

I'm sure with your fueling setup if you bumped up base pressure even just a little bit you could run pure E85 or even E98 without a problem. And maybe your ETS TMIC is maxed out, but I bet if fuel pressure and boost were increased a bit, even on your current TMIC, it would make more power.

I wonder if banging off fuel cut in 4th or 5th would max out the injectors from the greater load.

John told me the TMIC was heat soaking on the top end when on the dyno, but, on the street, especially in cooler weather, the motor would not drop off until past 7k rpm. For me, the car has more power than I know what to do with. You've driven it.

I simply haven't had a chance to bounce it in 4th, it's getting tougher and tougher to find an open road nowadays and that's over 100mph. Maybe when I'm on a bare freeway sometime I'll think about a quick 70-100-70 pull.

[K3rm1tth3fr0g]

Originally Posted by Dave D.

John told me the TMIC was heat soaking on the top end when on the dyno, but, on the street, especially in cooler weather, the motor would not drop off until past 7k rpm. For me, the car has more power than I know what to do with. You've driven it.

I simply haven't had a chance to bounce it in 4th, it's getting tougher and tougher to find an open road nowadays and that's over 100mph. Maybe when I'm on a bare freeway sometime I'll think about a quick 70-100-70 pull.

Fair enough . I am always trying my best to optimize my setup and get the most powah as possible, but you're right, your car is definitely a torque monster haha.

I was just getting at the fact that your E75 flex tune doesn't add more timing, boost when you add higher concentration fuel. It will just add more fuel based on the injector PW.

So when you ran your old E60 tune on E75 and made more WHP/WQ, I attribute that to just the higher octane of the E75 + the cooling factor. The tune just dumped more fuel at the same boost.

My point is just that I doubt John added in the tune to change parameters when ethanol content increases, when he didn't have the ability to verify those parameters on the dyno. Hence why tuning with the highest possible content fuel is ideal.