[jluetjen]

BTW, Given my engine's 9.9:1 performance on 93 octane (since 94 just went away this year), I'd hesitate suggesting that people go that high without twin plugging. My car starting pinging pretty bad with Sunoco 93, worse in fact then it has in the past on Texico 93. Right now I'm running a tank of Texico 93 with 1 gallon of Toluene which seems to work. I'm planning on doing the following as a result to try to clarify the choices.

1) Confirm the performance of 1 gal of Tuloene for a tank of gas. Intial results are that it seems to work.

2) Confirm the ignition timing that I have on the car.

3) Fill up the next tank full with straight 93 octane. Retard the ignition timing until it doesn't ping. Make note of any changes to the tuning (for example the idle speed).

4) Put the car on a dyno (hopefully as part of a Boston Area Dyno day) and try running both configurations. First half a tank 93 octane and retarded ignition timing. Then top off the tank with a mixture of 4 gallons of gas and 1 of Toluene and reset the ignition timing to what I have now and re-run it on the dyno.