The differing opinions in this thread are really interesting.

I am one of the engines Howard pulled apart that was running E85. The engine ran it for a little over 900 miles and had an alarming amount of buildup in the ports. This was a very hard buildup that took quite some time to dissolve before rebuilding the engine again. I was running 2oz/gal of Redline Racing Oil for premix and no OMP.

That all said I will be having the car tuned for flex fuel. This is so I can keep the setup simplistic and still have the advantages of E85 but the flexibility of 93 for road trips.

I am the type of guy that overbuilds everything, so I don't have to go back and do it again later. I have dual Walbro 450lph pumps on a custom hanger (very easy to do), -8 feed lines, -6 return, 4 2200cc Bosch Secondaries, 2 1000cc Bosch primaries, CJ Motorsports rails, Aeromotive FPR.

If your going to run E85 do some more reading and truly decide if it is for you.

 

My motor all it has its a streetport but stock internals and seals execept Apex seals. I don't want to run e85 if it's going to start messing with the selals in a year or over. That's what I want to know if it is going to be a problem to my motor. Anybody that has ran the motor over 3 to 5 years on e85 notice a problem during the time?

 

You have to cycle E10 and E85. You MUST do this. It's a well known issue of buildup with E85 that shows up even on OEM flex fuel cars. The only solution is to run E10 once in a while. With a flex fuel sensor it's not a big deal.

You run Straight E85 to strongly decrease the chances of a catastrophic knock event, which is usually what blows up engines. carbon buildup isn't a good thing, but it's causes are complicated, and it generally doesn't leave you on the side of the road running on one rotor.

Water/meth can do that too. You better hope nothing goes wrong with your system though, or hope your failsafes protect you.

 

i assume you are talking about 10% alchol. I have never seen that at a station. Does cycling 110 octane aviation fuel do the same thing? You guys are starting to worry me about the E85. How long were you running E85 before you tore it down and discovered buildup?

 

I was relating this thread to my wife, telling her that guys on the forum are having their engines gunk up when running E85. Her comment: "Maybe they're not driving it fast enough". Pretty good wife.

 

You've never seen a station with 87, 89, 91/93 gasoline? It all has up to 10% ethanol.

 

While we are on the subject. Is there a particular premix that plays well with E85 or better yet mitigates some of the concerns with E85?

 

When It comes to deposits, Don't overthink this. Every few months, put a tank of E10 in (almost every place in the US has around 10 percent ethanol). Then put E85 in again. If it's flex fuel tuned, you don't even have to think about it. If your ECU doesn't support that, you need separate tunes and have to be careful when switching between.

Don't go for 6 months or a year without ever putting normal fuel in there and you'll be fine. Don't do short trips on E85 to the grocery store over and over again without letting the engine warm up to boil off the Ethanol that doesn't vaporize as well.

 

Yes there is. After running the Klotz reg and Super tech stuff. I tried Red line. After not getting crap built up on the bottom of my Fuel jugs in just a couple days...I rebuilt my entire fuel system. I now only use Red Line and am lucky enough to call them my oil sponsor. If you don't want goo all over your engine internals, and fuel system. Use their synthetic alky premix.

 

for the record This is very outdated info

 

of course understanding evolves over time, in this case 6 years, but most of the general drift of this thread is correct. if you are running in the 400 area your general interests would be best served by running gasoline or gasoline w a minority interest of ethanol. while alcohol, in this case ethanol, is a better fuel than gasoline as to cooler burning it does lack the lubricity of gasoline. to the extent that ethanol is base fuel your rotor housings and apex seals will show increased wear.

this wear should not reduce compression because the seals and housings will "marry." should you need to change apex seals the housings will need to be properly honed or replaced.

during the last 3 years i have experimented with varying amounts (25-60%) of ethanol and have found as others that most of the benefits (lower EGTs and detonation) are obtained around 30/40% E.

FWIW, i use Benol as premix for the E portion of my base fuel. this is based on the rotor housing condition of someone who had been beating on (just above 600) his motor for 3 years. --- not scientific but perhaps better than theory.

i am probably the strongest proponent of the benefits of alcohol for our motors having run 100% methanol as AI since 2003. i have measured intake air coming out of the turbo (before the intercooler) since 2012. as well as IAT in the stock location.

IAT out of the turbo rises w boost and RPM. it can easily be 300-400 F, and more as you pass 500 hp..

a very good intercooler can remove around 67% of the increased temp from ambient. efficiency drops significantly w heat soak.

ambient is not outside air temp, it is the temp at the air filter. engine bay temp. probably around 125 near your filter IF it is not downstream from the intercooler. if it is, add an easy 25 F to ambient.

so looking at the dynamics:

350 out of the turbo - 200 out of the intercooler (IAT stock location) / 350 F - 125 (engine bay temp) = 67%

assuming 67% efficiency the intercooler removes 150 F leaving 200 F into the motor. to many using a thermistor as an IAT sensor this sounds high if not obscene. this is because any thermistor, including the "fast" ones are range bound as to time. the only accurate means of obtaining IATs is by using a thermocouple. four readings per second and accurate to plus or minus one degree at 200F.

here's a link to the sensor i use:

https://thesensorconnection.com/prod...rcharger?v=567

i run EGT Technologies sensor amps but there are other brands. Innovate has a 4 channel amp for just over $100.

here's a recent log that shows the benefits of alcohol.



the run isn't anything spectacular but the metrics ARE. just 15 psi boost and a lazy roll into the TPS. compressor output temps go from 180 cruising to 298 F. notice how IATs, the middle plot, initially rise w boost and then flatten and drop w the advent of the methanol AI..(the lower green plot.)

if we assume a 67% intercooler efficiency, 296.6 out of the turbo and 105 engine bay temp we find IATs into the motor should be 168.2. actual IAT was 106.9

my methanol AI dropped IATs another 61.3 F.

yes, i like alcohol in it's many forms... both as a partial base fuel and also as AI injectant. BTW, if you look at the right hand numbers i am running 32% E as base fuel.

i added my knock readings just to show that our motors do generate knock with combustion chamber pressure increases. the degree is important and in this case it is minimal.

that's my 2023 update w re to alcohol. what's yours?