A friend is using 100LL aviation fuel mixed with unleaded premium and he is very happy with the results.  I'm not sure of the price in NJ but it is not terribly more than premium.

He brings a couple of 5 gallon cans to the local airport and adds it @ home before a trip to the local gas stations.

I pay $2.95 for 100LL Avgas for my 59 Mooney here in Austin Texas.  But I expect it's going up with the next resupply at my local field.  There is a web site which gives the local prices of Avgas.  Try http://airnav.com/fuel/  100LL has a lot more lead than 93octane auto fuel.  I would mix it with the auto fuel If I were you.  I am not sure what the mix rate would be needed for 11:1.  My Lycoming is only 9:1 but requires at least 93 octane according to my owners manual.

John

Funny thing, I just bought back my 73.  It is stock L48 350 8.5:1 comp, and I bought a reprinted owners manual (some idiot PO lost or threw out my original one).  I read through it for the first time last night (never bothered to, back in 73 when I bought the car).  The owners manual recommends minimum 91 octane.  All the years (1973-1982) and 86,000 miles that I drove it I used regular unleaded 87octane (85 in the higher altitude states), and never had a problem.  I just drove it 2,400 miles back to Texas from Calif and put in reg unleaded all the way with no problem.  Why would GM recommend 91 octane for this engine????  I don't think I want to switch to premium at these pump prices, but I don't plan on driving it that much anyway.  I have my Valkrie for that!

John

Fuel quality was a bit different then.  And ratings varied.  There are three ratings,  Research method, Motor method, and research plus motor divided by 2, which is what is used now.

I honestly don't remember which rating GM used then, or if it's a different one then used today.    The VW Beetle at that time required 91, but it was the same as today's 87.  It was 91 RON   Research Octane Number.

Fuel was commonly rated as just regular or high test.

My Owners manual calls for 91 RON.  So 91 RON is the equalivant to 87 octane unleaded regular today?  In any case I have used regular ever since I owned the car with no ill effects.

John