While the 2.5i is tuned from the factory for 98oct fuel, there seems to be no trouble in running 95oct. I have always used BP Ultimate in my car as I had it tuned when I first bought it to get rid of the disappointing throttle and accelleration lag. I only chose BP for convenience.
Now that my car is heavily modified, running a stage II supercharger, I thought I would open the debate as to which fuel runs best. I would hope they have a similar level of performance, but just thought I'd see if anyone has any experiances to share? The good, the bad, the strange.
Logging data and insight from the tuners would be great.