DesmoSD

Those in CA, it's 10% Ethanol thanks to CARB.

http://www.energy.ca.gov/almanac/tra...a/ethanol.html

jamesinger

I don't want to be OT and it's apples to oranges but I drove on pure E85 for 5 years in one EVO and 3 years in another. The new owners of both cars are still running E85. One is the crazy green Navarez Racing Pike's peak EVO and the other is a private track/daily car that gets a ton of track days a year. I only had to fill up on 91 a few times in those years when I was on a trip or something and there was no E85 available. My Zeitronix gauge read over E10 on the CA 91. I upgraded my fuel pump and injectors + a tune for E85 besides other more common mods. I had zero ill effects. I know this is about porsche engines but in the 4G63 EVO VIII motor with a 2.0, and later with a 2.3 stroker motor built by RRE, E85 gave me close to 100 safe added HP/TQ on a mellow no knock tune...very addictive.

I am not arguing for Ethanol. I am just saying that when I ran it for many years, I had no negative impacts to the engine or other parts, and there was a big HP/TQ gain. These ethanol worries have been argued to DEATH on EVO forums but besides HP/TQ, I was really interested in "biofuels" at the time. ...not really as a solution but as a cleaner alternative.



2.3 4G63 RRE motor on E85


the same 2.3 4G63 RRE motor on 91

Sorry the pics. are so big. This motor has been raced hard for years and has not blown with this tune. Also, I did store the car at times with E85 in the tank and I just added stabilizers. Also, because each car were both track cars, and because I am a money wasting psycho, they got full fluid changes after 2-4 track days religiously.

ADias

Are you saying that CA 91 has more than 10% ethanol?

ADias

We know!

jamesinger

I would see up to E15 on 91 but normally it would be 7-12%. In all those years I only map switched a few times in emergencies, and it is important to note, I had E85 in the tank, drove on my 91 map with 91/E85 to empty, and then filled 91 again, so I do not think what I am saying is totally correct just because of running E85, blending, switching to 91 for a few tanks, and then switching back. For example, I would drive from LA to Tahoe, so that is like 4 tanks there and back? In any case, by the time I was on my 3rd tank or so, I would see an average of about 7% to 12%. The gauge is fairly cheap and mine was just in my glove box if anyone is interested. If you are interested less, there is also an analog gauge I never tried. Last, now there are flex maps that deal with this better but being in LA only and driving to SD to visit family, I never had any issues getting E85.

jamesinger

...oh, and E85 is never E85 either. I have seen up to E87 or so, and shockingly low values of down to E68. That is why I had the gauge. If I went WOT on E68 on an E85 tune, I would get insane knock. I'd be willing to bet it is rare for E85 to be 85% but more normal to be above E80 but below E85. The digital gauge was fun to have because you would see that kind of stuff and it was accurate.

​​​Here is the gauge in action used by my friend Simon


p.s. my car was WAY cleaner than my friend's. I just want to flag that he has an excessive amount of stuff in his car to the point where it was like a damn UFO. Haha.

p.p.s. LAST EDIT!! Sorry. I just emailed Mike W at RRE just to see what their GT3R is running, and it runs on 100 race fuel. I was curious to see if they were running E85 on their 911 car.

ADias

Interesting stuff. But for gas-powered cars pure gas is what we should have.

Ben Z

The only non-ethanol gas around here is 90 octane rec fuel and it's quite inconvenient to find. I run Shell Nitro 93 and add a bottle of Driven's Injector Defender every other tankful. I have Nickies sleeves and use DT40 oil in the 997, but I run the same gas and Defender in my stock LS3 Corvette. Hoping for the best.

Chris(MA)

Interesting thread and thanks for the heads up, I just installed the pure gas app on my phone.

On the 996 forum there are some threads on high oil consumption, sooty tailpipes and bore scoring. From my understanding (and summarizing) the ethanol attracts water, the water etc corrodes the injectors, an injector can then run rich. Combined with an air leak from a failing AOS or oil filler tube the ECU then ups the banks mixture to compensate.

With that one injector running rich if the engine spends a lot of time idling like in traffic (remember m96/m97 have 1.8 bar valves on the piston oil jets, so hot idle there is no oil being delivered to the piston) it causes bore wash, the first evidence is soot on a tailpipe.

If left unchecked the bore wash causes lack of lube between piston and cylinder and the piston coating is lost, the cylinder can then score. Another symptom of bore washing is high oil consumption, even on a new motor (because old failing injectors were used).

DesmoSD

Most of my Supra buddies are running E85, pushing nice numbers and burning very clean. I'm feel so tempted so build my Supra every time we hang out but damn CA smog every 2 yrs. The S366 spool is so awesome!

jamesinger

Smog was no issue for me with E85. One way I passed smog was to put the OEM cat back on and run my 91 tune with mostly 91 in the tank. My engine looked stock but was a fully built motor because of living in California.

The other way I passed smog was to just go in to a place where I knew the tech with no cat running E85, which yielded cleaner numbers than catted on 91 but with a nosey tech, would have failed.

I smogged my car 2-3 times while on E85 using the methods mentioned above.

I am not thinking of tuning my 997 on E85 and I am not trying to advocate people tuning for E85 but I have never seen any negative evidence on EVOs while hanging out at RRE and pretending to work there for years. All I saw was the ridiculous power it made and that is burns cleaner. If you run catless on 91 and stand near the car idling, your eyes will water the fumes are so strong. It stinks and is intense. On E85, you do not have the same issues. I would frequently sit at stop lights with cops catless on E85, and I never really got a second look—with a 3" turbo back exhaust. Oddly, in all the years I had EVOs, I never got pulled over in one. Both were highly modded.

997s were designed to run blended gas, so I am not worried about having ethanol in my tank from previous years of positive experience. Also, the octane rating for E85 was what interested me further in relation to tuning. I think E85 is equivalent to 108 octane but I might be a bit off. The ability to tune more aggressively on it and get more HP/TQ is why it is popular for cars like EVOs.

DesmoSD

The most problematic part with a smog test is passing the visual. Which EVO do you have and which smog? Is it sniffer/dyno or OBDII port? My Supra is still dyno/sniffer but my Tacoma is an 05 so it just gets the plug.

You have to replace the entire fuel system to run flex fuel. For the Supra, owners listed the items needed to safely run it. It does run better and smells much better then 91 pump gas.

jamesinger

I had 2 EVO VIIIs on both sniffer and OBD SMOGs from my memory. I definitely did sniffers not on the rollers because AWD. I feel that the last 2 I did were just OBD. The 2 OBD smogs I did were (1) lucky, and (2) friendly. The first one was a grandpa I used to go to because he was suuuuper lazy and DGAF unless you had what he called "shiny stuff" under the hood, or brightly colored clearly non OEM parts. The second one was a "friend." The thing is, unless they probed the exhaust, there was nothing that didn't look OEM on my EVO on purpose and my car would pass after visual no problem on either test. IDK what the deal is with Supras but SMOG is something that makes me want to barf every time I get it done, even on a stock car because it is so inconsistent.

DesmoSD

I hear ya. The one I go to is friendly since I have GReddy 3 row and that's the first thing you see are polished IC pipes and a bare aluminum radiator behind in the grille. lol Even thought I have the CARB printout from GReddy, they haven't asked about it. I'm still "relatively stock" but I have to swap the downpipe and remove the HKS BOV before I bring her in to get her a*s sniffed. lol

Saaboteur

Attended a tech session last weekend put on by the local PCA chapter (Polar Region) and some local Imperial/Mobil1 employees/club members. A few takeaways from the session that was news to me was that a) gasoline is a commodity, like wheat or whatever, and only differs between oil companies (other than octane rating) by the additives that each company throws in; b) Esso and now Mobil1 at the Superstore gas stations, at least in Alberta, have the same blend; c) Esso/Mobil1 91 octane Synergy is ethanol free.