TRUE? I have to burn ethanol, retard timing?

[Mark75H]

That is correct, but there are many other more important factors.

Exactly where are you going with the methanol idea and why have you brought up a third fuel?

[DuckLn]

I can say this about Arkansas filling stations: Our state regs are not sufficient and that is all i will say.

[microbream]

Methanol has a 50% lower BTU than gasoline, however the ideal methanol/air mixture is 1:5.5 which is more the 2.3 times fuel than if gasoline(1:13) is used, thus the heat produced is approx 17% more than petrol.
Ethanol is about 10% more than petrol.
flowing that amount of fuel requires a serious rejet though!

[microbream]

Adding ethanol to petrol will increase its octane number which allows you to run higher compression and advanced timing, For a while here in oz you could get cheap 95 octane E10 ethanol blend which was good in my opinion. But since then they have blended ethanol with lower grade petrol to give 90 octane crap IMO. Low fuel economy and poor power is hardly enviromentally sound!

stick with plane old high octane gasoline unless the ethanol added actually gives some octane advantage. We also had a 100 octane fuel available breifly which used ethanol to boost it octane number up, was popular with the turbo boys.

I guess the long and the short of it is, no, you should not have to retard timing if the octane number is as specified in your owners manual, regardless of what the fuel is blended from.

[Tim Kurcz]

Product Latent Heat of Evaporation (kJ/kg) / (Btu/lb)

Acetone 518 / 223
Alcohol, ethyl (ethanol) 846 / 364
Alcohol, methyl (methanol alcohol) 1100 / 473
Toluene 351 / 151
Water 2257 / 970.4

Here's why you want to run Methanol!

[microbream]

Becareful here, latent heat of evaporation refers to the amount of heat to convert from liquid to gas. and i quote:
Methanol and ethanol have a very high latent heat of vaporisation, i.e., it takes a
lot of heat to convert them from liquid form into vapour. Petrol has a latent heat of
evaporation of 135 Btu/lb., methanol 472 Btu/lb. and ethanol 410 Btu/lb. This heat,
required for proper atomisation, is removed from the piston crown, combustion
chamber and the cylinder, resulting in an internally cooler engine.
An engine burning methanol will usually show a 6-8% power increase over one
running on Avgas 100/130 (i.e., Racing Fuel 100), without any change in compression
ratio. With the compression ratio increased to its maximum, power can rise as much as
15-17%. Where does the power increase come from?
The two cycle engine is a type of heat engine, i.e., one that burns fuel to cause the
expansion of gas, and the subsequent movement of the piston. The more heat produced
by the combustion fire, the more pressure there will be exerted on the piston, which
gives us a power increase.
Using petrol, the fuel/air ratio for best power (i.e., the strongest force on the
piston) is 1:12.5. With methanol, for example, we can increase the fuel/air ratio to
1:4.5, although I usually prefer a ratio of 1:5.5; less than 1:7 is too lean.
One pound of petrol has the energy potential of about 19,000 Btu (one British
Thermal Unit is the amount of energy required to raise the temperature of one pound
of water one degree Fahrenheit.). In comparison, methanol delivers around 9,800
Btu/lb., which means that it produces less than 52% of the heat energy of lib of petrol.
However, because we are mixing more methanol with each pound of air (1:5.5) than
petrol (1:12.5), we are actually producing more heat energy by burning methanol.

[Fastjeff57]

Wanna go like a bat outta hell? Inject WM50 (water/ methanol 50 %) into the carb opening at full throttle. Virtually every WW II aircraft engine builder used that trick to prevent detonation, so they could run higher boost pressure and/ or compression ratios. The water and methanol effect the cooling without need of extra fuel, which you WOULD need with pure methanol. Far as I can determine, no fuel enrichment was ever added with the WM50, just the juice itself.

All you need is a tank, a windshield washer pump, a nozzle and some plumbing. I did that on several of my turbo cars running insanely high boost pressures, using a pressure switch to trigger the pump.

Jeff

[Mark75H]

Do you think spraying water into your bearings is a good idea?

[OUTBOARDER]

Great forum!
Opinion poll time:
An outboard service yard told me on my 1972 50 hp Johna/Rude fishin' mota, that runs on E10 (all we can get in Massachusetts) that I should not run at the stock timing setting of 19 degrees @ 5500 RPM: I should time to a setting at least 2 degrees less to have the engine hold together longer.

Is this fact or fiction?

Would the change in timing even make a difference the way it performs?

Thanks,
Bill

one gallon of BLUE THUNDER 30% NITRO / 70% Alky mixed with 5 gal 10% alky pump gas.
replace main jets with #70's set timing to 24 deg btdc you will notice it, get a big prop while your at it!

[Bill Gohr]

Wow glad this thread didn't run off on a different tangent