Is the main issue that you won't notice an improvement with lower octane, or are there more serious drawbacks such as pinging/knocking, etc...
Thanks!
- considering chipping but hate the potential gas bill with lengthy commute.

I don't know about the other chips, but I believe APR's chip is designed for 93 octane. You will not get optimal performance out of your chip if you use lower octane as the knock sensors may tell the computer to retard the timing if it detects potential pinging. Or worse yet, you may get knocking/pinging.

It is best to speak with the tuner you are interested in working with to find out what the minimum octane level is needed.

When I tried to run 91 octane (couldn't find another station - I was far from the city) the car ran fine, but under heavy load (full throttle up a hill at high speeds) I noticed some uneven power problems (where it seemed the power would be strong then back off, strong then back off, etc.). Once I went to the 94 octane that problem went away. Now I get smooth power.

I've also experimented with 92 Octane and it is probably borderline. Seems fine, so I'll use it when I can't find the 94 or cannot be bothered.

Wayne
99 1.8TQMS APR