Couldn't think of a better place to ask this question.
As a tuner, I've been tuning a lot of guys to run on e85 lately. It seems to be a good fuel for forced induction engines, relatively inexpensive for the local streetcar crowd around where I live. As long as you can find a place that blends it consistently, and watch AFRs, it seems to be a good gas for the money. With lower BTU, it's not exactly "mileage friendly" though.
There's a few guys however, who run 13B turbo Rotary engines, that are telling me they want to mix AvGas 100LL roughly 25% with pump gas (91-93 octane) to achieve a slight increase in octane. These guys can't run e85 because, with only 4 injectors, they can't get enough injector (without adding supplementary injectors) to support e85 under the kind of manifold pressure they like to run.
I've always been told by sources that I trust, that AvGas is a bad idea due to "different properties." I've tried reading up on fuels and understanding the properties, but it's taking me longer to grasp most of these than I have time to make recommendations to some of these guys.
Can anyone here tell me if I am being overly paranoid? SO, my actual question is: Assuming it's mixed consistently, is 100 Low Lead a good idea to mix with pump fuel (which I know is very inconsistent) for an increase in knock resistance?