Two questions?
 

1.Do any of you guys run Av gas in your boats? Other than the price are there any disadvantages?

2. Do any of you guys run the MSD Boost timing master or the adjustable timing control on your engines? I am thinking about buying one of them because it is kind of a PITA to adjust the timing when the headers are hot.

I have used the msd boost timing master on my vette. Works great, with just a turn of the knob.

Long ago and far away...
 

many moons ago Howard Quam and I used to burn aviation fuel in "Flap Jack". We had the old Kinsler timed fuel injection and rather than risk messing up the o-rings in the pump, we added oil to the fuel.

Aviation is very high in alcohol, (very dry), and it does attack rubber components.

Too much octane is not always a good thing.

what if you used the av gas as a booster,like making 93 a couple points higher,a cushion on detonation.

That was kind of my idea behind it.

How well did the kinsler injection work? I have always want to try something like that or a Hilborn setup on one of my toys. I love the way they look.

Av gas use to burn a lot hotter and could be a problem with burnt valves and such.

gasoline isn't simply gasoline. it's a mixture of many different things. aviation anything is fairly specific.. avgas is designed/formulated to run in moderate hp engines in a semi-oxygen deficient environment at a moderate consistant sustained RPM and a relatively cool air supply. it contains, among other things various anti icing additives plus the carbs have heatng elements to additionaly combat icing (how do I know this, my father ended up in a farmers field because he forgot to flip the switch) could you get away with running it? probably, is there a risk? yes. is it an acceptable risk? thats your call. race fuel is expensive, but it does come in much higher octane than avgas 112-116 vs. 100 so it can be diluted with regular fuel offsetting the cost. HTTP://www.bazellracefuels.com/Calcs/OC1.htm contains a calculator for figuring out octane mixing ratios. it is also important to know what octane you actually need, not what you think youneed or want. To high of octane will actually DECREASE power.

Here is my two cents, Av gas is formulated for laege bore, long stroke, low rpm engines which run at higher altitude. Av gas gigher octane is usefull for that, but it has a lower volitility so part throttle response sucks. It has a lower spific gravity so it will require a jet change or ecm tune. Av gas has a higher percenage of aromatics. That reduces throttle responce. Also Av gas octane numbers are not computed the same as motor octane numbers of race fuels and it is short on octane compared to race fuels. Many marine engines run more spark advanceat low to mid throttle than av gas and some unleaded fuels can handle. The rsult is detination. the bottom line is if your not over 10.5:1 your wasting your money. You should stick to good grade pump gas and tune to it. That will get you the best perfomance your engine can produce. Unless you use a hydometer and keep track of the specific gravity of your fuel mix your tune will always be off every time your fuel mixture changes.