So what are the pros and cons about advancing the timing on the b18c?

 

The spec for ignition timing is 16 deg. +/- 2 deg. BTDC. Many people take this to the end of the range and run 18 deg. BTDC. You can get a slight power increase (very slight), but you should always run premium fuel, 91 octane minimum (I only use 93 octane) if you do this. If you run less than 91, the knock sensor can retard timing to compensate, but it will have a more difficult time since it will have to retard the timing more than if you had it set at 16 deg. BTDC.

I have kept my B18C1 set at 18 BTDC ever since I did my first timing belt change on the car back in 2001.