Teach Me: For A Street Auto That Is Tuned -E"XX" Pump Gas, Methanol Fuel

OK, I am a bit confused on fuel choices these days and need some clarification. For the longest time, I just buy 87 octane unleaded, which I believe has 10% Ethanol. So that could also be called E10, correct?

For a "normal" average car, why is E85 offered?

I have a 1996 Ford Explorer that was happiest on 89 unleaded back in the day. Will the ethanol in today's fuel has a negative impact on its operation, if I elect to use it on a long trip?

In the near (or very distant) future, I may buy a Euro sedan equipped with a V8 and decent HP. Add a tad more HP after a modest tune. Of course 91 octane will be required. As long as I buy gas from Costco, QT, Shell, or any other top tier place, I should be OK, yes? Regarding a tune, I am aware of possibly needing larger injectors, Tmap sensors, higher capacity fuel pump and/or lines, etc.

RE: Methanol. I've seen cars with multiple tunes/mapping depending upon use and/or fuel. Why use methanol? Where can I buy it on a regular basis? What is its typical cost on a Gas Equivalent Gallon basis?

TIA.

 

For a while some engines were built/tuned to run on either. E85 is usually cheaper than 87 but you burn more so its a wash.

For a high performance engine using E85 instead of 91/93 oct its a lot cheaper, even though you use more. And you MAY be able to tune for more power with E85. Alcohol is more detonation resistant than gasoline. I think E85 is ~105 octane.

My BRZ needed 91 oct. I added flex fuel sensor and tuned it for E85. It made ~8-10% more HP on E85 than 91 tune. I could add either to tank and it had 91 tune, middle tune and pure e85 (E above 70 or so) tune. The ECU could select correct tune based on reading from sensor. Some cars/tuners cant do this.

If you need a tuner in ATL go see Doug at DBW motorsports.

 

1.) Correct.

2.) Agenda.

3.) <10% ethanol won’t hurt it. If the vehicle is labeled “Flex Fuel” you could run higher amounts, but, you’d need to closely read the owner’s manual to see for sure. ‘96 might be before it’s acceptance.

4.) The euro sedan MAY be flex fuel. If so, you can run anything you want, without further mods. However, E85 would be advantageous, as it’s more resistant to detonation and will allow the ECU to add more timing.

5.) No idea on methanol suppliers. VP?

My Silverado has higher compression pistons, cam, springs, and was tuned for IL fuel, which was E15. Moving to FL, it will not run on any pump gas, without detonation. I have to pussy foot the thing, if I let the ethanol content in the tank get too low. Periodically, I run up to the only station in the area with E85 and fill up.

 

exactly how much compression is in the cylinder? what kind of tuner was used that the timing cant be retarded or knock sensor wont intervene? The tuner cant send you a sea level tune? Was the pump & injectors sized to take the full advantage?
If anything... eth free comes in 92 octane flavor and is readily available from a pump & works plenty well for variable & static compression ratios up to 13.5:1 ala turbocharged.

 

I’m not sure what the actual compression ended up being. The heads originally paired with a dished piston. There are flat tops in there, now.

Not sure what software was used. The dude is in Idaho and I don’t have the ability to download a tune.

The knock sensors do intervene. But, any kind of throttle input will cause it to ping, before that. Definitely not the way to run it.

It’s not making enough power to require more pump or injectors.

I’ve tried non-ethanol (can’t remember the octane on the pump) and it pings.

In JAX and Pensacola, I had intermittent issues. In Fort Myers, everything rattles, no matter the station (same tank farm supplies all of them?). I did an E85 search and found a 76 station with it. That has taken care of it, until I can get a local tuner, which I’ve found, to take a look.

 

Methanol is in washer fluid so, depending on how much you're injecting, that'd be your cost per gallon.

Methanol increases the density of the air/fuel mixture

 

Primary gain with Methanol IIRC is it has a cooling effect when atomized, you can get away with big boost without an intercooler and not have your IATs go nutzso.

 

I experimented as a kid with my Honda CL125 single cylinder 4 stroke with menthanol.

I had to double the size of the main jet to flow enough fuel and I could pull over and lay my hand on the intake side of the head, right after the carb and it was cold.

 

Dont confuse Methanol and Ethanol, they are not the same. The big thing with either vs regular gas is their stoichiometric value. IE, how many parts of air per part of fuel to get the perfect burn. For gasoline its 14.7:1, for Ethanol its 9:1, for methanol its 6.5:1. You need more than double the fuel injected per air volume to keep the same ratio meth vs gas. This is the biggest "hurdle" of ethanol. because different ratios of ethanol to gas produce different stoichometric targets. Flex fuel cars either read the ethanol content via sensor (GM) or infer it via AFR readings. (Ford). What ford does is monitors the fuel levels in flex fuel capable vehicles and when it sees a large quantity of fuel added it assumes you filled up. It then looks at O2 sensor readings. It knows it needs to inject xx fuel at certain rpm/load to get stoich. If it injects xx and gets a lean reading it injects more, and it keeps adding until it gets stoich (its lambda but thats a whole nother can of worms). Once its "learned" the ethanol content it keeps that percentage of add/subtract.

Now, why is E85 so good? Its Octane is 108. Just that right there makes it poor mans race fuel. Where else can you go and pump 108 octane fuel thats cheaper than a gallon of 87 oct? Ethanol also has great cooling properties. Methanol even more, shit, on straight meth you dont even need an intercooler on turbo/supercharger cars. The evaporative cooling effects are so strong. Alcohols keep the cylinder temperature down, allowing you to run more timing, more boost, increasing cylinder pressure without having to worry as much about melting pistons, butting ring gaps, detonation and pinging. It also smells awesome!
My supercharged Coyote runs it and the engine bay stays way cooler on ethanol than on 94 oct. I went to the track and swapped fuels to see what it can do on both.
Coyotes are pretty much maxed out on 94 octane at around 700whp with a supercharger, probably closer to high 700s with a turbo. The octane rating is not enough to add any more boost or timing as the cylinder heat causes ring land failure. On Ethanol, that limit is closer to 1200whp+. In fact on Ethanol the rods will fold before you reach the knock limit.

Back to your 91 octane from anywhere question. Depends on year and sophistication of the ECU. All new ECUs pretty much constantly add timing looking for knock threshold, or pull timing from base timing if they detect knock. So you can run 91, or 89, or even 87, and the ECu will just give you the middle finger as it stares you in the eyes and pulls all timing from it. So a 91 octane from Shell may let the ECU add 3 degrees more timing, while Costco may not.

To the guy with the knocking LS. Your tuner is lazy. HPtuners tuned GMs have a bunch of adders and subtracters from maps. It can get pretty crazy trying to track why commanded timing map vs actual timing map are not the same. So a lot of tuners simply copy and paste the "wanted" timing map onto ALL the other "adders/subtractors" maps. Its meant to let them dial in the optimal timing/fuel map without chasing their tails. After thats done though they are supposed to go and remap the "high load/low load", the "knock threshold" maps that are there to protect the motor. IE. "Shit im seeing knock, what do i do? oh yea, i look up this other map, which tells me to pull 5 degrees in that RPM/load range" except that the map doesnt tell it to pull 5 degrees...

 

One thing Ive realized is that the eth content is very inconsistent with the standard pump fuels at low volume sellers. My prev employer had 2 instances where drivers got diesel with water in it.

 

Ethanol content in e85 can be as low as 50%. It’s never been mandated that it HAS to have 85 percent. In fact. There’s actually three “tiers” of e85 that gets sold based on time of year and location. Due to that wonderful cooling capacity and it’s predisposition to not burn easily (octane) cold starting on e85 can be a bitch. So in northern states in winter you are more likely to encounter e70 than e85. Helps with starting.

 

Sounds right, from what I know of HPT.

I’m going to stop by this other shop, this week, and see what he has to say. He’s done a lot of the fast stuff around here, so it should be a pretty easy deal for him. I don’t care if he restores the stock tune, at this point. It’s not a race truck.

 

There is a FB page for my area where a guy regularly tests the content, right at the pump, then, posts the number.

 

Unsung hero.

 

My 335d has an AEM methanol injection kit. I get 5s of M1 from VP for the meth tank.

https://vpracingfuels.com/product/m1/?c=215&

 

Almost cheaper than pump fuel!

 

Forgot to mention ... thanks everyone. I've learned a lot. If I ever go down the rabbit hole of tuning an auto, I will at least make less mistakes to begin with.

I need to stop watching Cleetus videos. I'm now even following his dentist brother's YT channel! Sigh, I need a life ...

 

You’d learn more from Sloppy Mechanics videos. You’d need to go all the way back to his early days of Fairmont #1, but, the guy explains everything there is to know about his builds and tuning them. He builds his own stuff, whereas Cleetus pays someone like Steve Morris.

 

Yeah, but Cleetus makes a lot of mistakes, usually of his own making, so I feel at home in that type of situation. :--)

I've also watched some Steve Morris stuff. What an incredible guy.

 

OK, another fuel related Q. I've never seen a variable ratio fuel being available like this - I guess naming it "flex fuel" was for a good reason. I'm assuming cars that can use it have some sort of way to measure ethanol level and report this data to an engine's ECU on a very timely basis? What is the sample rate - 60Hz, 1KHz?