In another recent thread I have been reading about the head aches involved with pump E-85 tuning.
I was not aware that this fuel is so inconsistent that you are better off just running it in your EFI engines.
I have been playing with a few carbs of my own that are fully tune able on the fly.
Its not easy to keep a handle on Iso/Meth/Eth/Xylene/Tolue/gasoline blends because of speed they separate and absorb water.
There is not E-85 where I live and so I blend my own fuels.
Consistent?
No I admit I add more Iso or Xylene even top oil on the go and I am constantly messing with screws.
Why not just run meth you say?
Or for that matter just gasoline?
Highest Octane I can get outside of 100LL is 91 and its probably all I need for my state of tune if If I add a bit of something to boost that ( that last part is hard to pin down ).
But Meth mix is nice if you can keep it mixed in because it makes a bit more power and drops your head temperature too.
Too much of it and the oil can get milky, you have to watch that and constantly keep from going to fat and washing out.
The tune on the fly carb can be quickly adapted to a fuel mixture ration change.
How much is surprising you know...
My last series 3 carb was supposed to be a lot more narrow ranged than the ones that proceeded it.
I think I screwed up on the numbers and ended up with a flat head carb ( those I find are richer in the first place, but the drilling data does not support this so it may be a difference in the Etube and air ports on the low side ).
What do you gain?
I guess it depends on what you want from a carb too.
I am going to shamelessly plug this carb again.
It continues to impress with its ease of tuning and I have not found the limits of its adjust ability.
I bet I could go to full meth, or very close.