Getting back to ya NNorton and to Oldskool, In my first build with this same set of 670s I ran a 67 GTO 400 in my bird. It was .030 over with 12 to 1 TRW pistons with (10.5 cc dome). I just used '104' octane booster. The gas was much better then, but I can't remember the mix, I remember with 12 to 1s though, if the gas was even one point lower or higher the engine was very sensitive to it. Now, with only 10.75 or so to 1, I can get away with the stuff I buy at the local parts store. Although I mix it way more than the bottle says. (Im sure their quoting a ratio for an average car with a little spark knock). Timing is important! Once you get the advance set just where you want, mix your fuel the same each time you fuel. I carry a little measuring cup and funnel in the trunk. Just ad the juice for the gallons you pump. I will check the brand I've been using and post it tomorrow.
