can octane be too high when using meth?
i.e in the uk our pump fuel is minimum 98
with 101 pump available at some stations!
so with your rule of thumb with 50/50
i'd possibly have octane of 125!
seems extreme when race fuel
is only between 100 - 116 iirc?

 

You are fortunate to have such good quality pump gas in the UK. Here in the states pump gas has about 10% ethanol added to it. So no telling what you are really getting.

Yes to much octane can be bad. The higher the octane the slower the burn of the air/fuel charge. To much and can loose power, basically referred to as quenching combustion when W/M is used.

Water meth will not give you much more octane then C116 race fuel. What we have seen in some dyno tests, gains are not much if using C116 and W/M over a tune with just C116. 93 pump gas and W/M, you will be able to make the same power or a little more, then running C116.

So with higher and higher octane base fuel, the amount of W/M needed would drop off.

 

what W/M ratio would give a 10% increase in octane rating?
i.e is it a linear change? 75W/25M would give 12.5% octane increase?

 

UK fuel octane is measured differently. Our 98 is like US 93.

 

tell me more! sorry for the hi-jack!

 

Have a read here http://en.wikipedia.org/wiki/Octane_rating

 

Interesting! so from what i can work out
with my limited brain power is
in the US they are what we in the UK
would class as 120+ Octane when running 50/50 W/M.
no wonder they make so much power

 

Im very curious to what negative side effects are of running meth/alky kits??? I was thinking of a meth kit on my Evo but its my daily driver that I plan on keeping for the next few years. What parts of the engine will be effected? Long term effects?.. etc Thanks!

 

bump as im also on the verge of getting one.
What i hear is that if it is installed correct it can't really do anything bad esspecially with all the failsafes they now have.

 

Good link, thanks for posting and clarifying between US and UK ratings.

 

Having to fill the tank is about the only downside. Most systems like ours are on demand injection. Only sprays when needed. Else it will "steam clean" the carbon buildup out of the intake also.

 

How often does the tank usually have to be filled up...i know it depends on how much you boost and how much is used but on average how much do you guys have to fill up your tank and what size?

 

i'm running water injection and pretty much
have a spirited drive daily covering
50miles a day and its 3 weeks between
full to empty on a 3L tank.

 

there are so many variables such as style of driving, where the trigger point is set, injector/nozzle size, mode of injection - on/off, IDC sync...and how much lead is in your foot.

this guy has 18 quarts and he can drain the triple tanks in a day or two

he is one extreme case

 

SlowCar - where is that photo of the six pack install ?