I am driving up to Tampa tommorrow to get my valves adjusted at 2nrwerks and on the way back I wanted to stop at Sunoco and fill up with 100 octane. How much can be safely be ran through safely?

 

There was already a debate on this some where else. Your computer wont adjust untill almost the end of the first tank, but the difference wont be very much (or even noticable) over premium grade unless your FI.

 

If it's leaded fuel do not put it in the car. You will destroy the 02 sensors and convertor.
On a stock car the possible performance gains from running slightly more ignition advance won't outweigh the $$ increase.

 

Anyone in the Dallas area know where to score some 100 octane?

 

You can reset the Ecu, by removing the positive (Red) from the battery for a minute.

You will ask the Ecu to start learning again on your new fuel...

 

If your car is stock unless there is a compelling reason to eke the most possible power from your car, stick with 93. Your wallet will thank you.