Gasoline powered boats and fuel consumption

[ttmott]

@PlayDate This is exactly how it is done in the Holley ECM-

 

[JayhawkCurtis]

First there is a couple of challenges - the fuel injectors need to be able to deliver the E85 mass flow yet stay below 80% duty cycle and have good idle characteristics on gasoline (PWM duty cycles around 1 ms) - it's a pretty tall order. That drives you to Peak and Hold low impedance injectors and specific ECMs for any higher horsepower applications. The big boys are running 16 injectors to get all to calibrate. Then the fuel system needs to be capable to deliver enough E85.
With the variable ratios of E85 and gasoline (you could have a 1/4 tank of gasoline then top up with E85), the ECM base fuel map becomes variable depending upon what the flex fuel sensor is indicating. Then the WBO2 sensors trim the base map to actual conditions. The trick is to keep the variability that the WBO2 sensors apply - like 5% deviation from the base map numbers optimally.

For the Holley system you can set it up in a Learn mode and it will populate and extrapolate the base map on one fuel then do the same on the other fuel. That will set up the base map(s) which is pretty good for street driving. But to do it right the car needs to be loaded on a dyno and the base maps refined. This is where the variability the WBO2 gets minimal and now the WBO2 is strictly optimizing the performance of the engine.

I dont understand a single thing in your post, but Im betting your car is going to be as cool as hell when you finish it.

 

[Scott215]

I love to fill my boat up with 100 octane low lead gas, I don't think they'll let me though I'd have to check the Hyannis airport lol

 

[ttmott]

There's a gas station on the road to my marina that sells Cam2. I've seen a couple of folks putting it in their boats.

I wonder what that costs - over thirty a gallon? CAM2 at our local drag strip is 32 per gallon.

 

[Jus Cruisin]

When I was in Florida, Wawa sold ethanol free gas and there was always some sort of flats boat or center console filling up. Way cheaper than on the water.
Around metro Detroit, there's a lot of badass barely legal street cars running around in the summer and a number of gas stations sell race gas. Gotta put it into gas jugs, not directly into the cars.

 

[ttmott]

When I was in Florida, Wawa sold ethanol free gas and there was always some sort of flats boat or center console filling up. Way cheaper than on the water.
Around metro Detroit, there's a lot of badass barely legal street cars running around in the summer and a number of gas stations sell race gas. Gotta put it into gas jugs, not directly into the cars.

Many of todays "race" fuels still use tetraethyl lead (TEL) as an additive for increased knock resistance, all the way up to even a research octane rating of 130. TEL in the 60's was the "lead" component in leaded fuel. It is highly toxic - statistics showed higher lead content in human blood in people that lived in high traffic cities and when TEL was removed from pump gasoline there was a dramatic shift in lead content in blood. TEL, however, is the most effective additive in gasoline for octane increases. A little goes a long way. The addition of TEL in gasoline does not affect the combusion flame speed which made it ideal as an additive. The downside to TEL on engines is the damaging effect it has on catalytic converters and oxygen sensors. For older engines TEL provided needed lubrication on valve seats but all modern engines have hardened valve seats now not requiring the lead.
Back when pump gas went to "unleaded" we were adding Toluene to the fuel. A gallon of toluene was around 6 bucks and it bumped three points according to the data we had at the time. It turned spark plugs a light tan color and made it impossible to "read the plugs" - ah the old days....
So if you are planning to operate your car or boat on "race fuel" or aviation 100LL be aware of the effects on the engine's components and emissions devices.
In my mind E85 even though not the effectiveness in raising octane as TEL is the best economical solution for high compression / forced induction performance engines with EFI driven on the streets. E85 has a research octane rating of 104.

 

[skibum]

I wonder what that costs - over thirty a gallon? CAM2 at our local drag strip is 32 per gallon.

I just called them. It's $14.99/gal today.

No way I'm buying 84 gallons of that. I don't care how fast it makes me go.

I'll bet it's way higher than that close to the drag strips around here, too. We have one regular gas station that is the closest to the exit from I-95 a couple of miles up the road from me. It's always 50-60 cents per gallon higher there because that's where a GPS shows as the closest if you are on the highway running on fumes. Go another half mile down and there's a half dozen stations with regular prices. Someone once told me if you went inside and told them you were a local, you'd get a lower price but I've never stopped in to check.

 

[Stray Current]

I originally only used the E0 when I moved down here but up in Jersey e10 was all that was available. I’ve since switched back to 89 octane e10 with 1oz/10 gallon treatment of stabil 360.

I see no appreciable difference in my gps derived fuel consumption between either, but I do get a little less timing advance on 87 vs 89 with my summer intake air temps. She’s definitely a bit more sluggish when it’s HOT and the 89 helps keep the knock sensor happy

The fact that I have a regular gas station that doesn’t carry e0 at the first turn into my neighborhood, and the nearest E0 is 5 miles across Cape retard plays no part in this decision