Methanol

[Gareth]

Since when did water reduce the octane rating? Not wishing to cause a debate, but i've heard it has no affect on octane rating.

[sdminus]

That a bit of a difficult question really and depends how you use it etc.

For 1 water is not a fuel and does not have a octane rating.
But water contains BTU's. Water has a higher BTU than petrol and methanol.

Water is 9 times more efficent at removing heat than petrol
Methanol is 3 times more efficent at removing heat than petrol

You could argue that if you replace petrol with water you will reduce the overall octane content. But water will help surpress det ( which you all seem shit scared of )

TBH petrol is a nasty cheap fuel.

methanol is pure but very dangerous.

Scott

[sdminus]

Water 970 BTU per pound..............lol
Methanol 472 BTU per pound..........stocih 6.4:1
Nitromethane 258 BTU per pound....stoich....2.1:1
Petrol 169 BTU per pound ..........stoich 14.7:1

Scott

[sdminus]

on the corrosive theme. I forgot to add that a WI pump ( shurflo ) with viton seals ( full methanol rated set up ) is only rated up to 100 hrs of life.
keep inmind this pump has stainless internals and viton seals. The methanol will still kill it in a short space of time. The only option is to run a crank driven pump

Scott

[Gareth]

For what its worth, i know of someone who has been running 20-40% methanol mix in his W.I system for over 8 years now, and it still performs as good as you would expect from ERL.

Whilst the people that know anything about engines and the way they work will argue that adding water to the inlet is a bad thing and takes up space that would otherwise be used by fuel/air, its benefits of reducing the intake temperature (which it does very well but not be a substitute for a decent FMIC) and surpressing detonation (the reason why i use it because i'm still on standard ECU) cannot be ignored.

I know for a fact my engine would have cracked ringlands running 17 +psi on standard ignition, even though i use 99+ octane fuel which seems to surpress it 7-10 times, the W.I eliminates det completely and gives me piece of mind, allows me to run more boost than i would without W.I and run more power as a result. I've seen the effect W.I does to power on the rollers at Emerald and although this will depend on set up, the engine in question lost 5bhp on the same boost, its used as an additional fail-safe and IMO for people on a budget works well, in an ideal world i would be on aftermarket management and dialling out excess advance, but i cant.

[sdminus]

The problem with water injection is you have to know how to tune with it.

You will loose power if you dont tune it correctly. IF its done well you will gain power.

Scott


trust me i get sponsorship from aquamist

[Gareth]

The problem with water injection is you have to know how to tune with it.

You will loose power if you dont tune it correctly. IF its done well you will gain power.

Scott


trust me i get sponsorship from aquamist

I understand completely. Problem is convincing non-believers that take what they read as gospel, but that goes for many things. As for the use of methanol as an octane booster you really do have to be careful because its a damn good degreaser of the bores when used in too high a concentration. I wouldnt use more than a 40% mix in my W.I system and prefer to use off the shelf octane booster from Millers because i know its proven and wont do my engine any harm.

[Stuart]

A great discussion this. We were all discussing this on the way back from the show today.........I was sitting there doing the sums too.

So why use methanol instead of a branded octane booster?

[sdminus]

Basically stu all you achieve by adding methanol is leaning out of the AFR's across the whole range by what ever percentage.


Methanol also has some other nasty side effects as well which will show up with the more added.

i will give you a couple more

1. Methanol will ping when it comes into contact with platinum ( spark plugs )
2. Will ping when is in a very lean mixture
3. will ping when in a very rich mixture

We can add these to the others i gave above

Scott

[Stuart]

So an octane booster will not suffer with these faults/ issues then Scott?

What does 'pinging' actually do? (In terms of cars not IT stuff )